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- env-llmeval/lib/python3.10/site-packages/scipy/conftest.py +238 -0
- env-llmeval/lib/python3.10/site-packages/scipy/interpolate/__init__.py +201 -0
- env-llmeval/lib/python3.10/site-packages/scipy/interpolate/__pycache__/__init__.cpython-310.pyc +0 -0
- env-llmeval/lib/python3.10/site-packages/scipy/interpolate/__pycache__/_bsplines.cpython-310.pyc +0 -0
- env-llmeval/lib/python3.10/site-packages/scipy/interpolate/__pycache__/_cubic.cpython-310.pyc +0 -0
- env-llmeval/lib/python3.10/site-packages/scipy/interpolate/__pycache__/_fitpack2.cpython-310.pyc +0 -0
- env-llmeval/lib/python3.10/site-packages/scipy/interpolate/__pycache__/_fitpack_impl.cpython-310.pyc +0 -0
- env-llmeval/lib/python3.10/site-packages/scipy/interpolate/__pycache__/_fitpack_py.cpython-310.pyc +0 -0
- env-llmeval/lib/python3.10/site-packages/scipy/interpolate/__pycache__/_interpolate.cpython-310.pyc +0 -0
- env-llmeval/lib/python3.10/site-packages/scipy/interpolate/__pycache__/_ndbspline.cpython-310.pyc +0 -0
- env-llmeval/lib/python3.10/site-packages/scipy/interpolate/__pycache__/_ndgriddata.cpython-310.pyc +0 -0
- env-llmeval/lib/python3.10/site-packages/scipy/interpolate/__pycache__/_pade.cpython-310.pyc +0 -0
- env-llmeval/lib/python3.10/site-packages/scipy/interpolate/__pycache__/_polyint.cpython-310.pyc +0 -0
- env-llmeval/lib/python3.10/site-packages/scipy/interpolate/__pycache__/_rbf.cpython-310.pyc +0 -0
- env-llmeval/lib/python3.10/site-packages/scipy/interpolate/__pycache__/_rbfinterp.cpython-310.pyc +0 -0
- env-llmeval/lib/python3.10/site-packages/scipy/interpolate/__pycache__/_rgi.cpython-310.pyc +0 -0
- env-llmeval/lib/python3.10/site-packages/scipy/interpolate/__pycache__/fitpack.cpython-310.pyc +0 -0
- env-llmeval/lib/python3.10/site-packages/scipy/interpolate/__pycache__/fitpack2.cpython-310.pyc +0 -0
- env-llmeval/lib/python3.10/site-packages/scipy/interpolate/__pycache__/interpolate.cpython-310.pyc +0 -0
- env-llmeval/lib/python3.10/site-packages/scipy/interpolate/__pycache__/ndgriddata.cpython-310.pyc +0 -0
- env-llmeval/lib/python3.10/site-packages/scipy/interpolate/__pycache__/polyint.cpython-310.pyc +0 -0
- env-llmeval/lib/python3.10/site-packages/scipy/interpolate/__pycache__/rbf.cpython-310.pyc +0 -0
- env-llmeval/lib/python3.10/site-packages/scipy/interpolate/_cubic.py +970 -0
- env-llmeval/lib/python3.10/site-packages/scipy/interpolate/_fitpack.cpython-310-x86_64-linux-gnu.so +0 -0
- env-llmeval/lib/python3.10/site-packages/scipy/interpolate/_fitpack_impl.py +805 -0
- env-llmeval/lib/python3.10/site-packages/scipy/interpolate/_fitpack_py.py +796 -0
- env-llmeval/lib/python3.10/site-packages/scipy/interpolate/_ndbspline.py +358 -0
- env-llmeval/lib/python3.10/site-packages/scipy/interpolate/_ndgriddata.py +332 -0
- env-llmeval/lib/python3.10/site-packages/scipy/interpolate/_polyint.py +938 -0
- env-llmeval/lib/python3.10/site-packages/scipy/interpolate/_rbf.py +290 -0
- env-llmeval/lib/python3.10/site-packages/scipy/interpolate/_rbfinterp.py +550 -0
- env-llmeval/lib/python3.10/site-packages/scipy/interpolate/_rgi.py +766 -0
- env-llmeval/lib/python3.10/site-packages/scipy/interpolate/_rgi_cython.cpython-310-x86_64-linux-gnu.so +0 -0
- env-llmeval/lib/python3.10/site-packages/scipy/interpolate/dfitpack.cpython-310-x86_64-linux-gnu.so +0 -0
- env-llmeval/lib/python3.10/site-packages/scipy/interpolate/fitpack.py +32 -0
- env-llmeval/lib/python3.10/site-packages/scipy/interpolate/ndgriddata.py +25 -0
- env-llmeval/lib/python3.10/site-packages/scipy/interpolate/rbf.py +25 -0
- env-llmeval/lib/python3.10/site-packages/scipy/interpolate/tests/__init__.py +0 -0
- env-llmeval/lib/python3.10/site-packages/scipy/interpolate/tests/__pycache__/__init__.cpython-310.pyc +0 -0
- env-llmeval/lib/python3.10/site-packages/scipy/interpolate/tests/__pycache__/test_bsplines.cpython-310.pyc +0 -0
- env-llmeval/lib/python3.10/site-packages/scipy/interpolate/tests/__pycache__/test_fitpack.cpython-310.pyc +0 -0
- env-llmeval/lib/python3.10/site-packages/scipy/interpolate/tests/__pycache__/test_fitpack2.cpython-310.pyc +0 -0
- env-llmeval/lib/python3.10/site-packages/scipy/interpolate/tests/__pycache__/test_gil.cpython-310.pyc +0 -0
- env-llmeval/lib/python3.10/site-packages/scipy/interpolate/tests/__pycache__/test_interpnd.cpython-310.pyc +0 -0
- env-llmeval/lib/python3.10/site-packages/scipy/interpolate/tests/__pycache__/test_interpolate.cpython-310.pyc +0 -0
- env-llmeval/lib/python3.10/site-packages/scipy/interpolate/tests/__pycache__/test_ndgriddata.cpython-310.pyc +0 -0
- env-llmeval/lib/python3.10/site-packages/scipy/interpolate/tests/__pycache__/test_pade.cpython-310.pyc +0 -0
- env-llmeval/lib/python3.10/site-packages/scipy/interpolate/tests/__pycache__/test_polyint.cpython-310.pyc +0 -0
- env-llmeval/lib/python3.10/site-packages/scipy/interpolate/tests/__pycache__/test_rbf.cpython-310.pyc +0 -0
- env-llmeval/lib/python3.10/site-packages/scipy/interpolate/tests/__pycache__/test_rbfinterp.cpython-310.pyc +0 -0
env-llmeval/lib/python3.10/site-packages/scipy/conftest.py
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1 |
+
# Pytest customization
|
2 |
+
import json
|
3 |
+
import os
|
4 |
+
import warnings
|
5 |
+
import tempfile
|
6 |
+
|
7 |
+
import numpy as np
|
8 |
+
import numpy.testing as npt
|
9 |
+
import pytest
|
10 |
+
import hypothesis
|
11 |
+
|
12 |
+
from scipy._lib._fpumode import get_fpu_mode
|
13 |
+
from scipy._lib._testutils import FPUModeChangeWarning
|
14 |
+
from scipy._lib import _pep440
|
15 |
+
from scipy._lib._array_api import SCIPY_ARRAY_API, SCIPY_DEVICE
|
16 |
+
|
17 |
+
|
18 |
+
def pytest_configure(config):
|
19 |
+
config.addinivalue_line("markers",
|
20 |
+
"slow: Tests that are very slow.")
|
21 |
+
config.addinivalue_line("markers",
|
22 |
+
"xslow: mark test as extremely slow (not run unless explicitly requested)")
|
23 |
+
config.addinivalue_line("markers",
|
24 |
+
"xfail_on_32bit: mark test as failing on 32-bit platforms")
|
25 |
+
try:
|
26 |
+
import pytest_timeout # noqa:F401
|
27 |
+
except Exception:
|
28 |
+
config.addinivalue_line(
|
29 |
+
"markers", 'timeout: mark a test for a non-default timeout')
|
30 |
+
config.addinivalue_line("markers",
|
31 |
+
"skip_if_array_api(*backends, reasons=None, np_only=False, cpu_only=False): "
|
32 |
+
"mark the desired skip configuration for the `skip_if_array_api` fixture.")
|
33 |
+
|
34 |
+
|
35 |
+
def _get_mark(item, name):
|
36 |
+
if _pep440.parse(pytest.__version__) >= _pep440.Version("3.6.0"):
|
37 |
+
mark = item.get_closest_marker(name)
|
38 |
+
else:
|
39 |
+
mark = item.get_marker(name)
|
40 |
+
return mark
|
41 |
+
|
42 |
+
|
43 |
+
def pytest_runtest_setup(item):
|
44 |
+
mark = _get_mark(item, "xslow")
|
45 |
+
if mark is not None:
|
46 |
+
try:
|
47 |
+
v = int(os.environ.get('SCIPY_XSLOW', '0'))
|
48 |
+
except ValueError:
|
49 |
+
v = False
|
50 |
+
if not v:
|
51 |
+
pytest.skip("very slow test; "
|
52 |
+
"set environment variable SCIPY_XSLOW=1 to run it")
|
53 |
+
mark = _get_mark(item, 'xfail_on_32bit')
|
54 |
+
if mark is not None and np.intp(0).itemsize < 8:
|
55 |
+
pytest.xfail(f'Fails on our 32-bit test platform(s): {mark.args[0]}')
|
56 |
+
|
57 |
+
# Older versions of threadpoolctl have an issue that may lead to this
|
58 |
+
# warning being emitted, see gh-14441
|
59 |
+
with npt.suppress_warnings() as sup:
|
60 |
+
sup.filter(pytest.PytestUnraisableExceptionWarning)
|
61 |
+
|
62 |
+
try:
|
63 |
+
from threadpoolctl import threadpool_limits
|
64 |
+
|
65 |
+
HAS_THREADPOOLCTL = True
|
66 |
+
except Exception: # observed in gh-14441: (ImportError, AttributeError)
|
67 |
+
# Optional dependency only. All exceptions are caught, for robustness
|
68 |
+
HAS_THREADPOOLCTL = False
|
69 |
+
|
70 |
+
if HAS_THREADPOOLCTL:
|
71 |
+
# Set the number of openmp threads based on the number of workers
|
72 |
+
# xdist is using to prevent oversubscription. Simplified version of what
|
73 |
+
# sklearn does (it can rely on threadpoolctl and its builtin OpenMP helper
|
74 |
+
# functions)
|
75 |
+
try:
|
76 |
+
xdist_worker_count = int(os.environ['PYTEST_XDIST_WORKER_COUNT'])
|
77 |
+
except KeyError:
|
78 |
+
# raises when pytest-xdist is not installed
|
79 |
+
return
|
80 |
+
|
81 |
+
if not os.getenv('OMP_NUM_THREADS'):
|
82 |
+
max_openmp_threads = os.cpu_count() // 2 # use nr of physical cores
|
83 |
+
threads_per_worker = max(max_openmp_threads // xdist_worker_count, 1)
|
84 |
+
try:
|
85 |
+
threadpool_limits(threads_per_worker, user_api='blas')
|
86 |
+
except Exception:
|
87 |
+
# May raise AttributeError for older versions of OpenBLAS.
|
88 |
+
# Catch any error for robustness.
|
89 |
+
return
|
90 |
+
|
91 |
+
|
92 |
+
@pytest.fixture(scope="function", autouse=True)
|
93 |
+
def check_fpu_mode(request):
|
94 |
+
"""
|
95 |
+
Check FPU mode was not changed during the test.
|
96 |
+
"""
|
97 |
+
old_mode = get_fpu_mode()
|
98 |
+
yield
|
99 |
+
new_mode = get_fpu_mode()
|
100 |
+
|
101 |
+
if old_mode != new_mode:
|
102 |
+
warnings.warn(f"FPU mode changed from {old_mode:#x} to {new_mode:#x} during "
|
103 |
+
"the test",
|
104 |
+
category=FPUModeChangeWarning, stacklevel=0)
|
105 |
+
|
106 |
+
|
107 |
+
# Array API backend handling
|
108 |
+
xp_available_backends = {'numpy': np}
|
109 |
+
|
110 |
+
if SCIPY_ARRAY_API and isinstance(SCIPY_ARRAY_API, str):
|
111 |
+
# fill the dict of backends with available libraries
|
112 |
+
try:
|
113 |
+
import array_api_strict
|
114 |
+
xp_available_backends.update({'array_api_strict': array_api_strict})
|
115 |
+
except ImportError:
|
116 |
+
pass
|
117 |
+
|
118 |
+
try:
|
119 |
+
import torch # type: ignore[import]
|
120 |
+
xp_available_backends.update({'pytorch': torch})
|
121 |
+
# can use `mps` or `cpu`
|
122 |
+
torch.set_default_device(SCIPY_DEVICE)
|
123 |
+
except ImportError:
|
124 |
+
pass
|
125 |
+
|
126 |
+
try:
|
127 |
+
import cupy # type: ignore[import]
|
128 |
+
xp_available_backends.update({'cupy': cupy})
|
129 |
+
except ImportError:
|
130 |
+
pass
|
131 |
+
|
132 |
+
# by default, use all available backends
|
133 |
+
if SCIPY_ARRAY_API.lower() not in ("1", "true"):
|
134 |
+
SCIPY_ARRAY_API_ = json.loads(SCIPY_ARRAY_API)
|
135 |
+
|
136 |
+
if 'all' in SCIPY_ARRAY_API_:
|
137 |
+
pass # same as True
|
138 |
+
else:
|
139 |
+
# only select a subset of backend by filtering out the dict
|
140 |
+
try:
|
141 |
+
xp_available_backends = {
|
142 |
+
backend: xp_available_backends[backend]
|
143 |
+
for backend in SCIPY_ARRAY_API_
|
144 |
+
}
|
145 |
+
except KeyError:
|
146 |
+
msg = f"'--array-api-backend' must be in {xp_available_backends.keys()}"
|
147 |
+
raise ValueError(msg)
|
148 |
+
|
149 |
+
if 'cupy' in xp_available_backends:
|
150 |
+
SCIPY_DEVICE = 'cuda'
|
151 |
+
|
152 |
+
array_api_compatible = pytest.mark.parametrize("xp", xp_available_backends.values())
|
153 |
+
|
154 |
+
|
155 |
+
@pytest.fixture
|
156 |
+
def skip_if_array_api(xp, request):
|
157 |
+
"""
|
158 |
+
Skip based on the ``skip_if_array_api`` marker.
|
159 |
+
|
160 |
+
Parameters
|
161 |
+
----------
|
162 |
+
*backends : tuple
|
163 |
+
Backends to skip, e.g. ``("array_api_strict", "torch")``.
|
164 |
+
These are overriden when ``np_only`` is ``True``, and are not
|
165 |
+
necessary to provide for non-CPU backends when ``cpu_only`` is ``True``.
|
166 |
+
reasons : list, optional
|
167 |
+
A list of reasons for each skip. When ``np_only`` is ``True``,
|
168 |
+
this should be a singleton list. Otherwise, this should be a list
|
169 |
+
of reasons, one for each corresponding backend in ``backends``.
|
170 |
+
If unprovided, default reasons are used. Note that it is not possible
|
171 |
+
to specify a custom reason with ``cpu_only``. Default: ``None``.
|
172 |
+
np_only : bool, optional
|
173 |
+
When ``True``, the test is skipped for all backends other
|
174 |
+
than the default NumPy backend. There is no need to provide
|
175 |
+
any ``backends`` in this case. To specify a reason, pass a
|
176 |
+
singleton list to ``reasons``. Default: ``False``.
|
177 |
+
cpu_only : bool, optional
|
178 |
+
When ``True``, the test is skipped on non-CPU devices.
|
179 |
+
There is no need to provide any ``backends`` in this case,
|
180 |
+
but any ``backends`` will also be skipped on the CPU.
|
181 |
+
Default: ``False``.
|
182 |
+
"""
|
183 |
+
if "skip_if_array_api" not in request.keywords:
|
184 |
+
return
|
185 |
+
backends = request.keywords["skip_if_array_api"].args
|
186 |
+
kwargs = request.keywords["skip_if_array_api"].kwargs
|
187 |
+
np_only = kwargs.get("np_only", False)
|
188 |
+
cpu_only = kwargs.get("cpu_only", False)
|
189 |
+
if np_only:
|
190 |
+
reasons = kwargs.get("reasons", ["do not run with non-NumPy backends."])
|
191 |
+
reason = reasons[0]
|
192 |
+
if xp.__name__ != 'numpy':
|
193 |
+
pytest.skip(reason=reason)
|
194 |
+
return
|
195 |
+
if cpu_only:
|
196 |
+
reason = "do not run with `SCIPY_ARRAY_API` set and not on CPU"
|
197 |
+
if SCIPY_ARRAY_API and SCIPY_DEVICE != 'cpu':
|
198 |
+
if xp.__name__ == 'cupy':
|
199 |
+
pytest.skip(reason=reason)
|
200 |
+
elif xp.__name__ == 'torch':
|
201 |
+
if 'cpu' not in torch.empty(0).device.type:
|
202 |
+
pytest.skip(reason=reason)
|
203 |
+
if backends is not None:
|
204 |
+
reasons = kwargs.get("reasons", False)
|
205 |
+
for i, backend in enumerate(backends):
|
206 |
+
if xp.__name__ == backend:
|
207 |
+
if not reasons:
|
208 |
+
reason = f"do not run with array API backend: {backend}"
|
209 |
+
else:
|
210 |
+
reason = reasons[i]
|
211 |
+
pytest.skip(reason=reason)
|
212 |
+
|
213 |
+
|
214 |
+
# Following the approach of NumPy's conftest.py...
|
215 |
+
# Use a known and persistent tmpdir for hypothesis' caches, which
|
216 |
+
# can be automatically cleared by the OS or user.
|
217 |
+
hypothesis.configuration.set_hypothesis_home_dir(
|
218 |
+
os.path.join(tempfile.gettempdir(), ".hypothesis")
|
219 |
+
)
|
220 |
+
|
221 |
+
# We register two custom profiles for SciPy - for details see
|
222 |
+
# https://hypothesis.readthedocs.io/en/latest/settings.html
|
223 |
+
# The first is designed for our own CI runs; the latter also
|
224 |
+
# forces determinism and is designed for use via scipy.test()
|
225 |
+
hypothesis.settings.register_profile(
|
226 |
+
name="nondeterministic", deadline=None, print_blob=True,
|
227 |
+
)
|
228 |
+
hypothesis.settings.register_profile(
|
229 |
+
name="deterministic",
|
230 |
+
deadline=None, print_blob=True, database=None, derandomize=True,
|
231 |
+
suppress_health_check=list(hypothesis.HealthCheck),
|
232 |
+
)
|
233 |
+
|
234 |
+
# Profile is currently set by environment variable `SCIPY_HYPOTHESIS_PROFILE`
|
235 |
+
# In the future, it would be good to work the choice into dev.py.
|
236 |
+
SCIPY_HYPOTHESIS_PROFILE = os.environ.get("SCIPY_HYPOTHESIS_PROFILE",
|
237 |
+
"deterministic")
|
238 |
+
hypothesis.settings.load_profile(SCIPY_HYPOTHESIS_PROFILE)
|
env-llmeval/lib/python3.10/site-packages/scipy/interpolate/__init__.py
ADDED
@@ -0,0 +1,201 @@
|
|
|
|
|
|
|
|
|
|
|
|
|
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|
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|
|
|
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|
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|
|
|
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|
|
|
|
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|
|
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|
|
|
|
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|
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|
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|
|
|
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|
|
|
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|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
1 |
+
"""
|
2 |
+
========================================
|
3 |
+
Interpolation (:mod:`scipy.interpolate`)
|
4 |
+
========================================
|
5 |
+
|
6 |
+
.. currentmodule:: scipy.interpolate
|
7 |
+
|
8 |
+
Sub-package for objects used in interpolation.
|
9 |
+
|
10 |
+
As listed below, this sub-package contains spline functions and classes,
|
11 |
+
1-D and multidimensional (univariate and multivariate)
|
12 |
+
interpolation classes, Lagrange and Taylor polynomial interpolators, and
|
13 |
+
wrappers for `FITPACK <http://www.netlib.org/dierckx/>`__
|
14 |
+
and DFITPACK functions.
|
15 |
+
|
16 |
+
Univariate interpolation
|
17 |
+
========================
|
18 |
+
|
19 |
+
.. autosummary::
|
20 |
+
:toctree: generated/
|
21 |
+
|
22 |
+
interp1d
|
23 |
+
BarycentricInterpolator
|
24 |
+
KroghInterpolator
|
25 |
+
barycentric_interpolate
|
26 |
+
krogh_interpolate
|
27 |
+
pchip_interpolate
|
28 |
+
CubicHermiteSpline
|
29 |
+
PchipInterpolator
|
30 |
+
Akima1DInterpolator
|
31 |
+
CubicSpline
|
32 |
+
PPoly
|
33 |
+
BPoly
|
34 |
+
|
35 |
+
|
36 |
+
Multivariate interpolation
|
37 |
+
==========================
|
38 |
+
|
39 |
+
Unstructured data:
|
40 |
+
|
41 |
+
.. autosummary::
|
42 |
+
:toctree: generated/
|
43 |
+
|
44 |
+
griddata
|
45 |
+
LinearNDInterpolator
|
46 |
+
NearestNDInterpolator
|
47 |
+
CloughTocher2DInterpolator
|
48 |
+
RBFInterpolator
|
49 |
+
Rbf
|
50 |
+
interp2d
|
51 |
+
|
52 |
+
For data on a grid:
|
53 |
+
|
54 |
+
.. autosummary::
|
55 |
+
:toctree: generated/
|
56 |
+
|
57 |
+
interpn
|
58 |
+
RegularGridInterpolator
|
59 |
+
RectBivariateSpline
|
60 |
+
|
61 |
+
.. seealso::
|
62 |
+
|
63 |
+
`scipy.ndimage.map_coordinates`
|
64 |
+
|
65 |
+
Tensor product polynomials:
|
66 |
+
|
67 |
+
.. autosummary::
|
68 |
+
:toctree: generated/
|
69 |
+
|
70 |
+
NdPPoly
|
71 |
+
NdBSpline
|
72 |
+
|
73 |
+
1-D Splines
|
74 |
+
===========
|
75 |
+
|
76 |
+
.. autosummary::
|
77 |
+
:toctree: generated/
|
78 |
+
|
79 |
+
BSpline
|
80 |
+
make_interp_spline
|
81 |
+
make_lsq_spline
|
82 |
+
make_smoothing_spline
|
83 |
+
|
84 |
+
Functional interface to FITPACK routines:
|
85 |
+
|
86 |
+
.. autosummary::
|
87 |
+
:toctree: generated/
|
88 |
+
|
89 |
+
splrep
|
90 |
+
splprep
|
91 |
+
splev
|
92 |
+
splint
|
93 |
+
sproot
|
94 |
+
spalde
|
95 |
+
splder
|
96 |
+
splantider
|
97 |
+
insert
|
98 |
+
|
99 |
+
Object-oriented FITPACK interface:
|
100 |
+
|
101 |
+
.. autosummary::
|
102 |
+
:toctree: generated/
|
103 |
+
|
104 |
+
UnivariateSpline
|
105 |
+
InterpolatedUnivariateSpline
|
106 |
+
LSQUnivariateSpline
|
107 |
+
|
108 |
+
|
109 |
+
|
110 |
+
2-D Splines
|
111 |
+
===========
|
112 |
+
|
113 |
+
For data on a grid:
|
114 |
+
|
115 |
+
.. autosummary::
|
116 |
+
:toctree: generated/
|
117 |
+
|
118 |
+
RectBivariateSpline
|
119 |
+
RectSphereBivariateSpline
|
120 |
+
|
121 |
+
For unstructured data:
|
122 |
+
|
123 |
+
.. autosummary::
|
124 |
+
:toctree: generated/
|
125 |
+
|
126 |
+
BivariateSpline
|
127 |
+
SmoothBivariateSpline
|
128 |
+
SmoothSphereBivariateSpline
|
129 |
+
LSQBivariateSpline
|
130 |
+
LSQSphereBivariateSpline
|
131 |
+
|
132 |
+
Low-level interface to FITPACK functions:
|
133 |
+
|
134 |
+
.. autosummary::
|
135 |
+
:toctree: generated/
|
136 |
+
|
137 |
+
bisplrep
|
138 |
+
bisplev
|
139 |
+
|
140 |
+
Additional tools
|
141 |
+
================
|
142 |
+
|
143 |
+
.. autosummary::
|
144 |
+
:toctree: generated/
|
145 |
+
|
146 |
+
lagrange
|
147 |
+
approximate_taylor_polynomial
|
148 |
+
pade
|
149 |
+
|
150 |
+
.. seealso::
|
151 |
+
|
152 |
+
`scipy.ndimage.map_coordinates`,
|
153 |
+
`scipy.ndimage.spline_filter`,
|
154 |
+
`scipy.signal.resample`,
|
155 |
+
`scipy.signal.bspline`,
|
156 |
+
`scipy.signal.gauss_spline`,
|
157 |
+
`scipy.signal.qspline1d`,
|
158 |
+
`scipy.signal.cspline1d`,
|
159 |
+
`scipy.signal.qspline1d_eval`,
|
160 |
+
`scipy.signal.cspline1d_eval`,
|
161 |
+
`scipy.signal.qspline2d`,
|
162 |
+
`scipy.signal.cspline2d`.
|
163 |
+
|
164 |
+
``pchip`` is an alias of `PchipInterpolator` for backward compatibility
|
165 |
+
(should not be used in new code).
|
166 |
+
"""
|
167 |
+
from ._interpolate import *
|
168 |
+
from ._fitpack_py import *
|
169 |
+
|
170 |
+
# New interface to fitpack library:
|
171 |
+
from ._fitpack2 import *
|
172 |
+
|
173 |
+
from ._rbf import Rbf
|
174 |
+
|
175 |
+
from ._rbfinterp import *
|
176 |
+
|
177 |
+
from ._polyint import *
|
178 |
+
|
179 |
+
from ._cubic import *
|
180 |
+
|
181 |
+
from ._ndgriddata import *
|
182 |
+
|
183 |
+
from ._bsplines import *
|
184 |
+
|
185 |
+
from ._pade import *
|
186 |
+
|
187 |
+
from ._rgi import *
|
188 |
+
|
189 |
+
from ._ndbspline import NdBSpline
|
190 |
+
|
191 |
+
# Deprecated namespaces, to be removed in v2.0.0
|
192 |
+
from . import fitpack, fitpack2, interpolate, ndgriddata, polyint, rbf
|
193 |
+
|
194 |
+
__all__ = [s for s in dir() if not s.startswith('_')]
|
195 |
+
|
196 |
+
from scipy._lib._testutils import PytestTester
|
197 |
+
test = PytestTester(__name__)
|
198 |
+
del PytestTester
|
199 |
+
|
200 |
+
# Backward compatibility
|
201 |
+
pchip = PchipInterpolator
|
env-llmeval/lib/python3.10/site-packages/scipy/interpolate/__pycache__/__init__.cpython-310.pyc
ADDED
Binary file (3.75 kB). View file
|
|
env-llmeval/lib/python3.10/site-packages/scipy/interpolate/__pycache__/_bsplines.cpython-310.pyc
ADDED
Binary file (63.9 kB). View file
|
|
env-llmeval/lib/python3.10/site-packages/scipy/interpolate/__pycache__/_cubic.cpython-310.pyc
ADDED
Binary file (30.8 kB). View file
|
|
env-llmeval/lib/python3.10/site-packages/scipy/interpolate/__pycache__/_fitpack2.cpython-310.pyc
ADDED
Binary file (82.6 kB). View file
|
|
env-llmeval/lib/python3.10/site-packages/scipy/interpolate/__pycache__/_fitpack_impl.cpython-310.pyc
ADDED
Binary file (22.6 kB). View file
|
|
env-llmeval/lib/python3.10/site-packages/scipy/interpolate/__pycache__/_fitpack_py.cpython-310.pyc
ADDED
Binary file (27.6 kB). View file
|
|
env-llmeval/lib/python3.10/site-packages/scipy/interpolate/__pycache__/_interpolate.cpython-310.pyc
ADDED
Binary file (71.2 kB). View file
|
|
env-llmeval/lib/python3.10/site-packages/scipy/interpolate/__pycache__/_ndbspline.cpython-310.pyc
ADDED
Binary file (11.2 kB). View file
|
|
env-llmeval/lib/python3.10/site-packages/scipy/interpolate/__pycache__/_ndgriddata.cpython-310.pyc
ADDED
Binary file (9.67 kB). View file
|
|
env-llmeval/lib/python3.10/site-packages/scipy/interpolate/__pycache__/_pade.cpython-310.pyc
ADDED
Binary file (2.09 kB). View file
|
|
env-llmeval/lib/python3.10/site-packages/scipy/interpolate/__pycache__/_polyint.cpython-310.pyc
ADDED
Binary file (32.1 kB). View file
|
|
env-llmeval/lib/python3.10/site-packages/scipy/interpolate/__pycache__/_rbf.cpython-310.pyc
ADDED
Binary file (11.1 kB). View file
|
|
env-llmeval/lib/python3.10/site-packages/scipy/interpolate/__pycache__/_rbfinterp.cpython-310.pyc
ADDED
Binary file (14.6 kB). View file
|
|
env-llmeval/lib/python3.10/site-packages/scipy/interpolate/__pycache__/_rgi.cpython-310.pyc
ADDED
Binary file (25.3 kB). View file
|
|
env-llmeval/lib/python3.10/site-packages/scipy/interpolate/__pycache__/fitpack.cpython-310.pyc
ADDED
Binary file (717 Bytes). View file
|
|
env-llmeval/lib/python3.10/site-packages/scipy/interpolate/__pycache__/fitpack2.cpython-310.pyc
ADDED
Binary file (930 Bytes). View file
|
|
env-llmeval/lib/python3.10/site-packages/scipy/interpolate/__pycache__/interpolate.cpython-310.pyc
ADDED
Binary file (883 Bytes). View file
|
|
env-llmeval/lib/python3.10/site-packages/scipy/interpolate/__pycache__/ndgriddata.cpython-310.pyc
ADDED
Binary file (723 Bytes). View file
|
|
env-llmeval/lib/python3.10/site-packages/scipy/interpolate/__pycache__/polyint.cpython-310.pyc
ADDED
Binary file (749 Bytes). View file
|
|
env-llmeval/lib/python3.10/site-packages/scipy/interpolate/__pycache__/rbf.cpython-310.pyc
ADDED
Binary file (636 Bytes). View file
|
|
env-llmeval/lib/python3.10/site-packages/scipy/interpolate/_cubic.py
ADDED
@@ -0,0 +1,970 @@
|
|
|
|
|
|
|
|
|
|
|
|
|
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|
|
1 |
+
"""Interpolation algorithms using piecewise cubic polynomials."""
|
2 |
+
|
3 |
+
from __future__ import annotations
|
4 |
+
|
5 |
+
from typing import TYPE_CHECKING
|
6 |
+
|
7 |
+
import warnings
|
8 |
+
|
9 |
+
import numpy as np
|
10 |
+
|
11 |
+
from scipy.linalg import solve, solve_banded
|
12 |
+
|
13 |
+
from . import PPoly
|
14 |
+
from ._polyint import _isscalar
|
15 |
+
|
16 |
+
if TYPE_CHECKING:
|
17 |
+
from typing import Literal
|
18 |
+
|
19 |
+
__all__ = ["CubicHermiteSpline", "PchipInterpolator", "pchip_interpolate",
|
20 |
+
"Akima1DInterpolator", "CubicSpline"]
|
21 |
+
|
22 |
+
|
23 |
+
def prepare_input(x, y, axis, dydx=None):
|
24 |
+
"""Prepare input for cubic spline interpolators.
|
25 |
+
|
26 |
+
All data are converted to numpy arrays and checked for correctness.
|
27 |
+
Axes equal to `axis` of arrays `y` and `dydx` are moved to be the 0th
|
28 |
+
axis. The value of `axis` is converted to lie in
|
29 |
+
[0, number of dimensions of `y`).
|
30 |
+
"""
|
31 |
+
|
32 |
+
x, y = map(np.asarray, (x, y))
|
33 |
+
if np.issubdtype(x.dtype, np.complexfloating):
|
34 |
+
raise ValueError("`x` must contain real values.")
|
35 |
+
x = x.astype(float)
|
36 |
+
|
37 |
+
if np.issubdtype(y.dtype, np.complexfloating):
|
38 |
+
dtype = complex
|
39 |
+
else:
|
40 |
+
dtype = float
|
41 |
+
|
42 |
+
if dydx is not None:
|
43 |
+
dydx = np.asarray(dydx)
|
44 |
+
if y.shape != dydx.shape:
|
45 |
+
raise ValueError("The shapes of `y` and `dydx` must be identical.")
|
46 |
+
if np.issubdtype(dydx.dtype, np.complexfloating):
|
47 |
+
dtype = complex
|
48 |
+
dydx = dydx.astype(dtype, copy=False)
|
49 |
+
|
50 |
+
y = y.astype(dtype, copy=False)
|
51 |
+
axis = axis % y.ndim
|
52 |
+
if x.ndim != 1:
|
53 |
+
raise ValueError("`x` must be 1-dimensional.")
|
54 |
+
if x.shape[0] < 2:
|
55 |
+
raise ValueError("`x` must contain at least 2 elements.")
|
56 |
+
if x.shape[0] != y.shape[axis]:
|
57 |
+
raise ValueError(f"The length of `y` along `axis`={axis} doesn't "
|
58 |
+
"match the length of `x`")
|
59 |
+
|
60 |
+
if not np.all(np.isfinite(x)):
|
61 |
+
raise ValueError("`x` must contain only finite values.")
|
62 |
+
if not np.all(np.isfinite(y)):
|
63 |
+
raise ValueError("`y` must contain only finite values.")
|
64 |
+
|
65 |
+
if dydx is not None and not np.all(np.isfinite(dydx)):
|
66 |
+
raise ValueError("`dydx` must contain only finite values.")
|
67 |
+
|
68 |
+
dx = np.diff(x)
|
69 |
+
if np.any(dx <= 0):
|
70 |
+
raise ValueError("`x` must be strictly increasing sequence.")
|
71 |
+
|
72 |
+
y = np.moveaxis(y, axis, 0)
|
73 |
+
if dydx is not None:
|
74 |
+
dydx = np.moveaxis(dydx, axis, 0)
|
75 |
+
|
76 |
+
return x, dx, y, axis, dydx
|
77 |
+
|
78 |
+
|
79 |
+
class CubicHermiteSpline(PPoly):
|
80 |
+
"""Piecewise-cubic interpolator matching values and first derivatives.
|
81 |
+
|
82 |
+
The result is represented as a `PPoly` instance.
|
83 |
+
|
84 |
+
Parameters
|
85 |
+
----------
|
86 |
+
x : array_like, shape (n,)
|
87 |
+
1-D array containing values of the independent variable.
|
88 |
+
Values must be real, finite and in strictly increasing order.
|
89 |
+
y : array_like
|
90 |
+
Array containing values of the dependent variable. It can have
|
91 |
+
arbitrary number of dimensions, but the length along ``axis``
|
92 |
+
(see below) must match the length of ``x``. Values must be finite.
|
93 |
+
dydx : array_like
|
94 |
+
Array containing derivatives of the dependent variable. It can have
|
95 |
+
arbitrary number of dimensions, but the length along ``axis``
|
96 |
+
(see below) must match the length of ``x``. Values must be finite.
|
97 |
+
axis : int, optional
|
98 |
+
Axis along which `y` is assumed to be varying. Meaning that for
|
99 |
+
``x[i]`` the corresponding values are ``np.take(y, i, axis=axis)``.
|
100 |
+
Default is 0.
|
101 |
+
extrapolate : {bool, 'periodic', None}, optional
|
102 |
+
If bool, determines whether to extrapolate to out-of-bounds points
|
103 |
+
based on first and last intervals, or to return NaNs. If 'periodic',
|
104 |
+
periodic extrapolation is used. If None (default), it is set to True.
|
105 |
+
|
106 |
+
Attributes
|
107 |
+
----------
|
108 |
+
x : ndarray, shape (n,)
|
109 |
+
Breakpoints. The same ``x`` which was passed to the constructor.
|
110 |
+
c : ndarray, shape (4, n-1, ...)
|
111 |
+
Coefficients of the polynomials on each segment. The trailing
|
112 |
+
dimensions match the dimensions of `y`, excluding ``axis``.
|
113 |
+
For example, if `y` is 1-D, then ``c[k, i]`` is a coefficient for
|
114 |
+
``(x-x[i])**(3-k)`` on the segment between ``x[i]`` and ``x[i+1]``.
|
115 |
+
axis : int
|
116 |
+
Interpolation axis. The same axis which was passed to the
|
117 |
+
constructor.
|
118 |
+
|
119 |
+
Methods
|
120 |
+
-------
|
121 |
+
__call__
|
122 |
+
derivative
|
123 |
+
antiderivative
|
124 |
+
integrate
|
125 |
+
roots
|
126 |
+
|
127 |
+
See Also
|
128 |
+
--------
|
129 |
+
Akima1DInterpolator : Akima 1D interpolator.
|
130 |
+
PchipInterpolator : PCHIP 1-D monotonic cubic interpolator.
|
131 |
+
CubicSpline : Cubic spline data interpolator.
|
132 |
+
PPoly : Piecewise polynomial in terms of coefficients and breakpoints
|
133 |
+
|
134 |
+
Notes
|
135 |
+
-----
|
136 |
+
If you want to create a higher-order spline matching higher-order
|
137 |
+
derivatives, use `BPoly.from_derivatives`.
|
138 |
+
|
139 |
+
References
|
140 |
+
----------
|
141 |
+
.. [1] `Cubic Hermite spline
|
142 |
+
<https://en.wikipedia.org/wiki/Cubic_Hermite_spline>`_
|
143 |
+
on Wikipedia.
|
144 |
+
"""
|
145 |
+
|
146 |
+
def __init__(self, x, y, dydx, axis=0, extrapolate=None):
|
147 |
+
if extrapolate is None:
|
148 |
+
extrapolate = True
|
149 |
+
|
150 |
+
x, dx, y, axis, dydx = prepare_input(x, y, axis, dydx)
|
151 |
+
|
152 |
+
dxr = dx.reshape([dx.shape[0]] + [1] * (y.ndim - 1))
|
153 |
+
slope = np.diff(y, axis=0) / dxr
|
154 |
+
t = (dydx[:-1] + dydx[1:] - 2 * slope) / dxr
|
155 |
+
|
156 |
+
c = np.empty((4, len(x) - 1) + y.shape[1:], dtype=t.dtype)
|
157 |
+
c[0] = t / dxr
|
158 |
+
c[1] = (slope - dydx[:-1]) / dxr - t
|
159 |
+
c[2] = dydx[:-1]
|
160 |
+
c[3] = y[:-1]
|
161 |
+
|
162 |
+
super().__init__(c, x, extrapolate=extrapolate)
|
163 |
+
self.axis = axis
|
164 |
+
|
165 |
+
|
166 |
+
class PchipInterpolator(CubicHermiteSpline):
|
167 |
+
r"""PCHIP 1-D monotonic cubic interpolation.
|
168 |
+
|
169 |
+
``x`` and ``y`` are arrays of values used to approximate some function f,
|
170 |
+
with ``y = f(x)``. The interpolant uses monotonic cubic splines
|
171 |
+
to find the value of new points. (PCHIP stands for Piecewise Cubic
|
172 |
+
Hermite Interpolating Polynomial).
|
173 |
+
|
174 |
+
Parameters
|
175 |
+
----------
|
176 |
+
x : ndarray, shape (npoints, )
|
177 |
+
A 1-D array of monotonically increasing real values. ``x`` cannot
|
178 |
+
include duplicate values (otherwise f is overspecified)
|
179 |
+
y : ndarray, shape (..., npoints, ...)
|
180 |
+
A N-D array of real values. ``y``'s length along the interpolation
|
181 |
+
axis must be equal to the length of ``x``. Use the ``axis``
|
182 |
+
parameter to select the interpolation axis.
|
183 |
+
|
184 |
+
.. deprecated:: 1.13.0
|
185 |
+
Complex data is deprecated and will raise an error in SciPy 1.15.0.
|
186 |
+
If you are trying to use the real components of the passed array,
|
187 |
+
use ``np.real`` on ``y``.
|
188 |
+
|
189 |
+
axis : int, optional
|
190 |
+
Axis in the ``y`` array corresponding to the x-coordinate values. Defaults
|
191 |
+
to ``axis=0``.
|
192 |
+
extrapolate : bool, optional
|
193 |
+
Whether to extrapolate to out-of-bounds points based on first
|
194 |
+
and last intervals, or to return NaNs.
|
195 |
+
|
196 |
+
Methods
|
197 |
+
-------
|
198 |
+
__call__
|
199 |
+
derivative
|
200 |
+
antiderivative
|
201 |
+
roots
|
202 |
+
|
203 |
+
See Also
|
204 |
+
--------
|
205 |
+
CubicHermiteSpline : Piecewise-cubic interpolator.
|
206 |
+
Akima1DInterpolator : Akima 1D interpolator.
|
207 |
+
CubicSpline : Cubic spline data interpolator.
|
208 |
+
PPoly : Piecewise polynomial in terms of coefficients and breakpoints.
|
209 |
+
|
210 |
+
Notes
|
211 |
+
-----
|
212 |
+
The interpolator preserves monotonicity in the interpolation data and does
|
213 |
+
not overshoot if the data is not smooth.
|
214 |
+
|
215 |
+
The first derivatives are guaranteed to be continuous, but the second
|
216 |
+
derivatives may jump at :math:`x_k`.
|
217 |
+
|
218 |
+
Determines the derivatives at the points :math:`x_k`, :math:`f'_k`,
|
219 |
+
by using PCHIP algorithm [1]_.
|
220 |
+
|
221 |
+
Let :math:`h_k = x_{k+1} - x_k`, and :math:`d_k = (y_{k+1} - y_k) / h_k`
|
222 |
+
are the slopes at internal points :math:`x_k`.
|
223 |
+
If the signs of :math:`d_k` and :math:`d_{k-1}` are different or either of
|
224 |
+
them equals zero, then :math:`f'_k = 0`. Otherwise, it is given by the
|
225 |
+
weighted harmonic mean
|
226 |
+
|
227 |
+
.. math::
|
228 |
+
|
229 |
+
\frac{w_1 + w_2}{f'_k} = \frac{w_1}{d_{k-1}} + \frac{w_2}{d_k}
|
230 |
+
|
231 |
+
where :math:`w_1 = 2 h_k + h_{k-1}` and :math:`w_2 = h_k + 2 h_{k-1}`.
|
232 |
+
|
233 |
+
The end slopes are set using a one-sided scheme [2]_.
|
234 |
+
|
235 |
+
|
236 |
+
References
|
237 |
+
----------
|
238 |
+
.. [1] F. N. Fritsch and J. Butland,
|
239 |
+
A method for constructing local
|
240 |
+
monotone piecewise cubic interpolants,
|
241 |
+
SIAM J. Sci. Comput., 5(2), 300-304 (1984).
|
242 |
+
:doi:`10.1137/0905021`.
|
243 |
+
.. [2] see, e.g., C. Moler, Numerical Computing with Matlab, 2004.
|
244 |
+
:doi:`10.1137/1.9780898717952`
|
245 |
+
|
246 |
+
"""
|
247 |
+
|
248 |
+
def __init__(self, x, y, axis=0, extrapolate=None):
|
249 |
+
x, _, y, axis, _ = prepare_input(x, y, axis)
|
250 |
+
if np.iscomplexobj(y):
|
251 |
+
msg = ("`PchipInterpolator` only works with real values for `y`. "
|
252 |
+
"Passing an array with a complex dtype for `y` is deprecated "
|
253 |
+
"and will raise an error in SciPy 1.15.0. If you are trying to "
|
254 |
+
"use the real components of the passed array, use `np.real` on "
|
255 |
+
"the array before passing to `PchipInterpolator`.")
|
256 |
+
warnings.warn(msg, DeprecationWarning, stacklevel=2)
|
257 |
+
xp = x.reshape((x.shape[0],) + (1,)*(y.ndim-1))
|
258 |
+
dk = self._find_derivatives(xp, y)
|
259 |
+
super().__init__(x, y, dk, axis=0, extrapolate=extrapolate)
|
260 |
+
self.axis = axis
|
261 |
+
|
262 |
+
@staticmethod
|
263 |
+
def _edge_case(h0, h1, m0, m1):
|
264 |
+
# one-sided three-point estimate for the derivative
|
265 |
+
d = ((2*h0 + h1)*m0 - h0*m1) / (h0 + h1)
|
266 |
+
|
267 |
+
# try to preserve shape
|
268 |
+
mask = np.sign(d) != np.sign(m0)
|
269 |
+
mask2 = (np.sign(m0) != np.sign(m1)) & (np.abs(d) > 3.*np.abs(m0))
|
270 |
+
mmm = (~mask) & mask2
|
271 |
+
|
272 |
+
d[mask] = 0.
|
273 |
+
d[mmm] = 3.*m0[mmm]
|
274 |
+
|
275 |
+
return d
|
276 |
+
|
277 |
+
@staticmethod
|
278 |
+
def _find_derivatives(x, y):
|
279 |
+
# Determine the derivatives at the points y_k, d_k, by using
|
280 |
+
# PCHIP algorithm is:
|
281 |
+
# We choose the derivatives at the point x_k by
|
282 |
+
# Let m_k be the slope of the kth segment (between k and k+1)
|
283 |
+
# If m_k=0 or m_{k-1}=0 or sgn(m_k) != sgn(m_{k-1}) then d_k == 0
|
284 |
+
# else use weighted harmonic mean:
|
285 |
+
# w_1 = 2h_k + h_{k-1}, w_2 = h_k + 2h_{k-1}
|
286 |
+
# 1/d_k = 1/(w_1 + w_2)*(w_1 / m_k + w_2 / m_{k-1})
|
287 |
+
# where h_k is the spacing between x_k and x_{k+1}
|
288 |
+
y_shape = y.shape
|
289 |
+
if y.ndim == 1:
|
290 |
+
# So that _edge_case doesn't end up assigning to scalars
|
291 |
+
x = x[:, None]
|
292 |
+
y = y[:, None]
|
293 |
+
|
294 |
+
hk = x[1:] - x[:-1]
|
295 |
+
mk = (y[1:] - y[:-1]) / hk
|
296 |
+
|
297 |
+
if y.shape[0] == 2:
|
298 |
+
# edge case: only have two points, use linear interpolation
|
299 |
+
dk = np.zeros_like(y)
|
300 |
+
dk[0] = mk
|
301 |
+
dk[1] = mk
|
302 |
+
return dk.reshape(y_shape)
|
303 |
+
|
304 |
+
smk = np.sign(mk)
|
305 |
+
condition = (smk[1:] != smk[:-1]) | (mk[1:] == 0) | (mk[:-1] == 0)
|
306 |
+
|
307 |
+
w1 = 2*hk[1:] + hk[:-1]
|
308 |
+
w2 = hk[1:] + 2*hk[:-1]
|
309 |
+
|
310 |
+
# values where division by zero occurs will be excluded
|
311 |
+
# by 'condition' afterwards
|
312 |
+
with np.errstate(divide='ignore', invalid='ignore'):
|
313 |
+
whmean = (w1/mk[:-1] + w2/mk[1:]) / (w1 + w2)
|
314 |
+
|
315 |
+
dk = np.zeros_like(y)
|
316 |
+
dk[1:-1][condition] = 0.0
|
317 |
+
dk[1:-1][~condition] = 1.0 / whmean[~condition]
|
318 |
+
|
319 |
+
# special case endpoints, as suggested in
|
320 |
+
# Cleve Moler, Numerical Computing with MATLAB, Chap 3.6 (pchiptx.m)
|
321 |
+
dk[0] = PchipInterpolator._edge_case(hk[0], hk[1], mk[0], mk[1])
|
322 |
+
dk[-1] = PchipInterpolator._edge_case(hk[-1], hk[-2], mk[-1], mk[-2])
|
323 |
+
|
324 |
+
return dk.reshape(y_shape)
|
325 |
+
|
326 |
+
|
327 |
+
def pchip_interpolate(xi, yi, x, der=0, axis=0):
|
328 |
+
"""
|
329 |
+
Convenience function for pchip interpolation.
|
330 |
+
|
331 |
+
xi and yi are arrays of values used to approximate some function f,
|
332 |
+
with ``yi = f(xi)``. The interpolant uses monotonic cubic splines
|
333 |
+
to find the value of new points x and the derivatives there.
|
334 |
+
|
335 |
+
See `scipy.interpolate.PchipInterpolator` for details.
|
336 |
+
|
337 |
+
Parameters
|
338 |
+
----------
|
339 |
+
xi : array_like
|
340 |
+
A sorted list of x-coordinates, of length N.
|
341 |
+
yi : array_like
|
342 |
+
A 1-D array of real values. `yi`'s length along the interpolation
|
343 |
+
axis must be equal to the length of `xi`. If N-D array, use axis
|
344 |
+
parameter to select correct axis.
|
345 |
+
|
346 |
+
.. deprecated:: 1.13.0
|
347 |
+
Complex data is deprecated and will raise an error in
|
348 |
+
SciPy 1.15.0. If you are trying to use the real components of
|
349 |
+
the passed array, use ``np.real`` on `yi`.
|
350 |
+
|
351 |
+
x : scalar or array_like
|
352 |
+
Of length M.
|
353 |
+
der : int or list, optional
|
354 |
+
Derivatives to extract. The 0th derivative can be included to
|
355 |
+
return the function value.
|
356 |
+
axis : int, optional
|
357 |
+
Axis in the yi array corresponding to the x-coordinate values.
|
358 |
+
|
359 |
+
Returns
|
360 |
+
-------
|
361 |
+
y : scalar or array_like
|
362 |
+
The result, of length R or length M or M by R.
|
363 |
+
|
364 |
+
See Also
|
365 |
+
--------
|
366 |
+
PchipInterpolator : PCHIP 1-D monotonic cubic interpolator.
|
367 |
+
|
368 |
+
Examples
|
369 |
+
--------
|
370 |
+
We can interpolate 2D observed data using pchip interpolation:
|
371 |
+
|
372 |
+
>>> import numpy as np
|
373 |
+
>>> import matplotlib.pyplot as plt
|
374 |
+
>>> from scipy.interpolate import pchip_interpolate
|
375 |
+
>>> x_observed = np.linspace(0.0, 10.0, 11)
|
376 |
+
>>> y_observed = np.sin(x_observed)
|
377 |
+
>>> x = np.linspace(min(x_observed), max(x_observed), num=100)
|
378 |
+
>>> y = pchip_interpolate(x_observed, y_observed, x)
|
379 |
+
>>> plt.plot(x_observed, y_observed, "o", label="observation")
|
380 |
+
>>> plt.plot(x, y, label="pchip interpolation")
|
381 |
+
>>> plt.legend()
|
382 |
+
>>> plt.show()
|
383 |
+
|
384 |
+
"""
|
385 |
+
P = PchipInterpolator(xi, yi, axis=axis)
|
386 |
+
|
387 |
+
if der == 0:
|
388 |
+
return P(x)
|
389 |
+
elif _isscalar(der):
|
390 |
+
return P.derivative(der)(x)
|
391 |
+
else:
|
392 |
+
return [P.derivative(nu)(x) for nu in der]
|
393 |
+
|
394 |
+
|
395 |
+
class Akima1DInterpolator(CubicHermiteSpline):
|
396 |
+
r"""
|
397 |
+
Akima interpolator
|
398 |
+
|
399 |
+
Fit piecewise cubic polynomials, given vectors x and y. The interpolation
|
400 |
+
method by Akima uses a continuously differentiable sub-spline built from
|
401 |
+
piecewise cubic polynomials. The resultant curve passes through the given
|
402 |
+
data points and will appear smooth and natural.
|
403 |
+
|
404 |
+
Parameters
|
405 |
+
----------
|
406 |
+
x : ndarray, shape (npoints, )
|
407 |
+
1-D array of monotonically increasing real values.
|
408 |
+
y : ndarray, shape (..., npoints, ...)
|
409 |
+
N-D array of real values. The length of ``y`` along the interpolation axis
|
410 |
+
must be equal to the length of ``x``. Use the ``axis`` parameter to
|
411 |
+
select the interpolation axis.
|
412 |
+
|
413 |
+
.. deprecated:: 1.13.0
|
414 |
+
Complex data is deprecated and will raise an error in SciPy 1.15.0.
|
415 |
+
If you are trying to use the real components of the passed array,
|
416 |
+
use ``np.real`` on ``y``.
|
417 |
+
|
418 |
+
axis : int, optional
|
419 |
+
Axis in the ``y`` array corresponding to the x-coordinate values. Defaults
|
420 |
+
to ``axis=0``.
|
421 |
+
method : {'akima', 'makima'}, optional
|
422 |
+
If ``"makima"``, use the modified Akima interpolation [2]_.
|
423 |
+
Defaults to ``"akima"``, use the Akima interpolation [1]_.
|
424 |
+
|
425 |
+
.. versionadded:: 1.13.0
|
426 |
+
|
427 |
+
Methods
|
428 |
+
-------
|
429 |
+
__call__
|
430 |
+
derivative
|
431 |
+
antiderivative
|
432 |
+
roots
|
433 |
+
|
434 |
+
See Also
|
435 |
+
--------
|
436 |
+
PchipInterpolator : PCHIP 1-D monotonic cubic interpolator.
|
437 |
+
CubicSpline : Cubic spline data interpolator.
|
438 |
+
PPoly : Piecewise polynomial in terms of coefficients and breakpoints
|
439 |
+
|
440 |
+
Notes
|
441 |
+
-----
|
442 |
+
.. versionadded:: 0.14
|
443 |
+
|
444 |
+
Use only for precise data, as the fitted curve passes through the given
|
445 |
+
points exactly. This routine is useful for plotting a pleasingly smooth
|
446 |
+
curve through a few given points for purposes of plotting.
|
447 |
+
|
448 |
+
Let :math:`\delta_i = (y_{i+1} - y_i) / (x_{i+1} - x_i)` be the slopes of
|
449 |
+
the interval :math:`\left[x_i, x_{i+1}\right)`. Akima's derivative at
|
450 |
+
:math:`x_i` is defined as:
|
451 |
+
|
452 |
+
.. math::
|
453 |
+
|
454 |
+
d_i = \frac{w_1}{w_1 + w_2}\delta_{i-1} + \frac{w_2}{w_1 + w_2}\delta_i
|
455 |
+
|
456 |
+
In the Akima interpolation [1]_ (``method="akima"``), the weights are:
|
457 |
+
|
458 |
+
.. math::
|
459 |
+
|
460 |
+
\begin{aligned}
|
461 |
+
w_1 &= |\delta_{i+1} - \delta_i| \\
|
462 |
+
w_2 &= |\delta_{i-1} - \delta_{i-2}|
|
463 |
+
\end{aligned}
|
464 |
+
|
465 |
+
In the modified Akima interpolation [2]_ (``method="makima"``),
|
466 |
+
to eliminate overshoot and avoid edge cases of both numerator and
|
467 |
+
denominator being equal to 0, the weights are modified as follows:
|
468 |
+
|
469 |
+
.. math::
|
470 |
+
|
471 |
+
\begin{align*}
|
472 |
+
w_1 &= |\delta_{i+1} - \delta_i| + |\delta_{i+1} + \delta_i| / 2 \\
|
473 |
+
w_2 &= |\delta_{i-1} - \delta_{i-2}| + |\delta_{i-1} + \delta_{i-2}| / 2
|
474 |
+
\end{align*}
|
475 |
+
|
476 |
+
Examples
|
477 |
+
--------
|
478 |
+
Comparison of ``method="akima"`` and ``method="makima"``:
|
479 |
+
|
480 |
+
>>> import numpy as np
|
481 |
+
>>> from scipy.interpolate import Akima1DInterpolator
|
482 |
+
>>> import matplotlib.pyplot as plt
|
483 |
+
>>> x = np.linspace(1, 7, 7)
|
484 |
+
>>> y = np.array([-1, -1, -1, 0, 1, 1, 1])
|
485 |
+
>>> xs = np.linspace(min(x), max(x), num=100)
|
486 |
+
>>> y_akima = Akima1DInterpolator(x, y, method="akima")(xs)
|
487 |
+
>>> y_makima = Akima1DInterpolator(x, y, method="makima")(xs)
|
488 |
+
|
489 |
+
>>> fig, ax = plt.subplots()
|
490 |
+
>>> ax.plot(x, y, "o", label="data")
|
491 |
+
>>> ax.plot(xs, y_akima, label="akima")
|
492 |
+
>>> ax.plot(xs, y_makima, label="makima")
|
493 |
+
>>> ax.legend()
|
494 |
+
>>> fig.show()
|
495 |
+
|
496 |
+
The overshoot that occured in ``"akima"`` has been avoided in ``"makima"``.
|
497 |
+
|
498 |
+
References
|
499 |
+
----------
|
500 |
+
.. [1] A new method of interpolation and smooth curve fitting based
|
501 |
+
on local procedures. Hiroshi Akima, J. ACM, October 1970, 17(4),
|
502 |
+
589-602. :doi:`10.1145/321607.321609`
|
503 |
+
.. [2] Makima Piecewise Cubic Interpolation. Cleve Moler and Cosmin Ionita, 2019.
|
504 |
+
https://blogs.mathworks.com/cleve/2019/04/29/makima-piecewise-cubic-interpolation/
|
505 |
+
|
506 |
+
"""
|
507 |
+
|
508 |
+
def __init__(self, x, y, axis=0, *, method: Literal["akima", "makima"]="akima"):
|
509 |
+
if method not in {"akima", "makima"}:
|
510 |
+
raise NotImplementedError(f"`method`={method} is unsupported.")
|
511 |
+
# Original implementation in MATLAB by N. Shamsundar (BSD licensed), see
|
512 |
+
# https://www.mathworks.com/matlabcentral/fileexchange/1814-akima-interpolation
|
513 |
+
x, dx, y, axis, _ = prepare_input(x, y, axis)
|
514 |
+
|
515 |
+
if np.iscomplexobj(y):
|
516 |
+
msg = ("`Akima1DInterpolator` only works with real values for `y`. "
|
517 |
+
"Passing an array with a complex dtype for `y` is deprecated "
|
518 |
+
"and will raise an error in SciPy 1.15.0. If you are trying to "
|
519 |
+
"use the real components of the passed array, use `np.real` on "
|
520 |
+
"the array before passing to `Akima1DInterpolator`.")
|
521 |
+
warnings.warn(msg, DeprecationWarning, stacklevel=2)
|
522 |
+
|
523 |
+
# determine slopes between breakpoints
|
524 |
+
m = np.empty((x.size + 3, ) + y.shape[1:])
|
525 |
+
dx = dx[(slice(None), ) + (None, ) * (y.ndim - 1)]
|
526 |
+
m[2:-2] = np.diff(y, axis=0) / dx
|
527 |
+
|
528 |
+
# add two additional points on the left ...
|
529 |
+
m[1] = 2. * m[2] - m[3]
|
530 |
+
m[0] = 2. * m[1] - m[2]
|
531 |
+
# ... and on the right
|
532 |
+
m[-2] = 2. * m[-3] - m[-4]
|
533 |
+
m[-1] = 2. * m[-2] - m[-3]
|
534 |
+
|
535 |
+
# if m1 == m2 != m3 == m4, the slope at the breakpoint is not
|
536 |
+
# defined. This is the fill value:
|
537 |
+
t = .5 * (m[3:] + m[:-3])
|
538 |
+
# get the denominator of the slope t
|
539 |
+
dm = np.abs(np.diff(m, axis=0))
|
540 |
+
if method == "makima":
|
541 |
+
pm = np.abs(m[1:] + m[:-1])
|
542 |
+
f1 = dm[2:] + 0.5 * pm[2:]
|
543 |
+
f2 = dm[:-2] + 0.5 * pm[:-2]
|
544 |
+
else:
|
545 |
+
f1 = dm[2:]
|
546 |
+
f2 = dm[:-2]
|
547 |
+
f12 = f1 + f2
|
548 |
+
# These are the mask of where the slope at breakpoint is defined:
|
549 |
+
ind = np.nonzero(f12 > 1e-9 * np.max(f12, initial=-np.inf))
|
550 |
+
x_ind, y_ind = ind[0], ind[1:]
|
551 |
+
# Set the slope at breakpoint
|
552 |
+
t[ind] = (f1[ind] * m[(x_ind + 1,) + y_ind] +
|
553 |
+
f2[ind] * m[(x_ind + 2,) + y_ind]) / f12[ind]
|
554 |
+
|
555 |
+
super().__init__(x, y, t, axis=0, extrapolate=False)
|
556 |
+
self.axis = axis
|
557 |
+
|
558 |
+
def extend(self, c, x, right=True):
|
559 |
+
raise NotImplementedError("Extending a 1-D Akima interpolator is not "
|
560 |
+
"yet implemented")
|
561 |
+
|
562 |
+
# These are inherited from PPoly, but they do not produce an Akima
|
563 |
+
# interpolator. Hence stub them out.
|
564 |
+
@classmethod
|
565 |
+
def from_spline(cls, tck, extrapolate=None):
|
566 |
+
raise NotImplementedError("This method does not make sense for "
|
567 |
+
"an Akima interpolator.")
|
568 |
+
|
569 |
+
@classmethod
|
570 |
+
def from_bernstein_basis(cls, bp, extrapolate=None):
|
571 |
+
raise NotImplementedError("This method does not make sense for "
|
572 |
+
"an Akima interpolator.")
|
573 |
+
|
574 |
+
|
575 |
+
class CubicSpline(CubicHermiteSpline):
|
576 |
+
"""Cubic spline data interpolator.
|
577 |
+
|
578 |
+
Interpolate data with a piecewise cubic polynomial which is twice
|
579 |
+
continuously differentiable [1]_. The result is represented as a `PPoly`
|
580 |
+
instance with breakpoints matching the given data.
|
581 |
+
|
582 |
+
Parameters
|
583 |
+
----------
|
584 |
+
x : array_like, shape (n,)
|
585 |
+
1-D array containing values of the independent variable.
|
586 |
+
Values must be real, finite and in strictly increasing order.
|
587 |
+
y : array_like
|
588 |
+
Array containing values of the dependent variable. It can have
|
589 |
+
arbitrary number of dimensions, but the length along ``axis``
|
590 |
+
(see below) must match the length of ``x``. Values must be finite.
|
591 |
+
axis : int, optional
|
592 |
+
Axis along which `y` is assumed to be varying. Meaning that for
|
593 |
+
``x[i]`` the corresponding values are ``np.take(y, i, axis=axis)``.
|
594 |
+
Default is 0.
|
595 |
+
bc_type : string or 2-tuple, optional
|
596 |
+
Boundary condition type. Two additional equations, given by the
|
597 |
+
boundary conditions, are required to determine all coefficients of
|
598 |
+
polynomials on each segment [2]_.
|
599 |
+
|
600 |
+
If `bc_type` is a string, then the specified condition will be applied
|
601 |
+
at both ends of a spline. Available conditions are:
|
602 |
+
|
603 |
+
* 'not-a-knot' (default): The first and second segment at a curve end
|
604 |
+
are the same polynomial. It is a good default when there is no
|
605 |
+
information on boundary conditions.
|
606 |
+
* 'periodic': The interpolated functions is assumed to be periodic
|
607 |
+
of period ``x[-1] - x[0]``. The first and last value of `y` must be
|
608 |
+
identical: ``y[0] == y[-1]``. This boundary condition will result in
|
609 |
+
``y'[0] == y'[-1]`` and ``y''[0] == y''[-1]``.
|
610 |
+
* 'clamped': The first derivative at curves ends are zero. Assuming
|
611 |
+
a 1D `y`, ``bc_type=((1, 0.0), (1, 0.0))`` is the same condition.
|
612 |
+
* 'natural': The second derivative at curve ends are zero. Assuming
|
613 |
+
a 1D `y`, ``bc_type=((2, 0.0), (2, 0.0))`` is the same condition.
|
614 |
+
|
615 |
+
If `bc_type` is a 2-tuple, the first and the second value will be
|
616 |
+
applied at the curve start and end respectively. The tuple values can
|
617 |
+
be one of the previously mentioned strings (except 'periodic') or a
|
618 |
+
tuple `(order, deriv_values)` allowing to specify arbitrary
|
619 |
+
derivatives at curve ends:
|
620 |
+
|
621 |
+
* `order`: the derivative order, 1 or 2.
|
622 |
+
* `deriv_value`: array_like containing derivative values, shape must
|
623 |
+
be the same as `y`, excluding ``axis`` dimension. For example, if
|
624 |
+
`y` is 1-D, then `deriv_value` must be a scalar. If `y` is 3-D with
|
625 |
+
the shape (n0, n1, n2) and axis=2, then `deriv_value` must be 2-D
|
626 |
+
and have the shape (n0, n1).
|
627 |
+
extrapolate : {bool, 'periodic', None}, optional
|
628 |
+
If bool, determines whether to extrapolate to out-of-bounds points
|
629 |
+
based on first and last intervals, or to return NaNs. If 'periodic',
|
630 |
+
periodic extrapolation is used. If None (default), ``extrapolate`` is
|
631 |
+
set to 'periodic' for ``bc_type='periodic'`` and to True otherwise.
|
632 |
+
|
633 |
+
Attributes
|
634 |
+
----------
|
635 |
+
x : ndarray, shape (n,)
|
636 |
+
Breakpoints. The same ``x`` which was passed to the constructor.
|
637 |
+
c : ndarray, shape (4, n-1, ...)
|
638 |
+
Coefficients of the polynomials on each segment. The trailing
|
639 |
+
dimensions match the dimensions of `y`, excluding ``axis``.
|
640 |
+
For example, if `y` is 1-d, then ``c[k, i]`` is a coefficient for
|
641 |
+
``(x-x[i])**(3-k)`` on the segment between ``x[i]`` and ``x[i+1]``.
|
642 |
+
axis : int
|
643 |
+
Interpolation axis. The same axis which was passed to the
|
644 |
+
constructor.
|
645 |
+
|
646 |
+
Methods
|
647 |
+
-------
|
648 |
+
__call__
|
649 |
+
derivative
|
650 |
+
antiderivative
|
651 |
+
integrate
|
652 |
+
roots
|
653 |
+
|
654 |
+
See Also
|
655 |
+
--------
|
656 |
+
Akima1DInterpolator : Akima 1D interpolator.
|
657 |
+
PchipInterpolator : PCHIP 1-D monotonic cubic interpolator.
|
658 |
+
PPoly : Piecewise polynomial in terms of coefficients and breakpoints.
|
659 |
+
|
660 |
+
Notes
|
661 |
+
-----
|
662 |
+
Parameters `bc_type` and ``extrapolate`` work independently, i.e. the
|
663 |
+
former controls only construction of a spline, and the latter only
|
664 |
+
evaluation.
|
665 |
+
|
666 |
+
When a boundary condition is 'not-a-knot' and n = 2, it is replaced by
|
667 |
+
a condition that the first derivative is equal to the linear interpolant
|
668 |
+
slope. When both boundary conditions are 'not-a-knot' and n = 3, the
|
669 |
+
solution is sought as a parabola passing through given points.
|
670 |
+
|
671 |
+
When 'not-a-knot' boundary conditions is applied to both ends, the
|
672 |
+
resulting spline will be the same as returned by `splrep` (with ``s=0``)
|
673 |
+
and `InterpolatedUnivariateSpline`, but these two methods use a
|
674 |
+
representation in B-spline basis.
|
675 |
+
|
676 |
+
.. versionadded:: 0.18.0
|
677 |
+
|
678 |
+
Examples
|
679 |
+
--------
|
680 |
+
In this example the cubic spline is used to interpolate a sampled sinusoid.
|
681 |
+
You can see that the spline continuity property holds for the first and
|
682 |
+
second derivatives and violates only for the third derivative.
|
683 |
+
|
684 |
+
>>> import numpy as np
|
685 |
+
>>> from scipy.interpolate import CubicSpline
|
686 |
+
>>> import matplotlib.pyplot as plt
|
687 |
+
>>> x = np.arange(10)
|
688 |
+
>>> y = np.sin(x)
|
689 |
+
>>> cs = CubicSpline(x, y)
|
690 |
+
>>> xs = np.arange(-0.5, 9.6, 0.1)
|
691 |
+
>>> fig, ax = plt.subplots(figsize=(6.5, 4))
|
692 |
+
>>> ax.plot(x, y, 'o', label='data')
|
693 |
+
>>> ax.plot(xs, np.sin(xs), label='true')
|
694 |
+
>>> ax.plot(xs, cs(xs), label="S")
|
695 |
+
>>> ax.plot(xs, cs(xs, 1), label="S'")
|
696 |
+
>>> ax.plot(xs, cs(xs, 2), label="S''")
|
697 |
+
>>> ax.plot(xs, cs(xs, 3), label="S'''")
|
698 |
+
>>> ax.set_xlim(-0.5, 9.5)
|
699 |
+
>>> ax.legend(loc='lower left', ncol=2)
|
700 |
+
>>> plt.show()
|
701 |
+
|
702 |
+
In the second example, the unit circle is interpolated with a spline. A
|
703 |
+
periodic boundary condition is used. You can see that the first derivative
|
704 |
+
values, ds/dx=0, ds/dy=1 at the periodic point (1, 0) are correctly
|
705 |
+
computed. Note that a circle cannot be exactly represented by a cubic
|
706 |
+
spline. To increase precision, more breakpoints would be required.
|
707 |
+
|
708 |
+
>>> theta = 2 * np.pi * np.linspace(0, 1, 5)
|
709 |
+
>>> y = np.c_[np.cos(theta), np.sin(theta)]
|
710 |
+
>>> cs = CubicSpline(theta, y, bc_type='periodic')
|
711 |
+
>>> print("ds/dx={:.1f} ds/dy={:.1f}".format(cs(0, 1)[0], cs(0, 1)[1]))
|
712 |
+
ds/dx=0.0 ds/dy=1.0
|
713 |
+
>>> xs = 2 * np.pi * np.linspace(0, 1, 100)
|
714 |
+
>>> fig, ax = plt.subplots(figsize=(6.5, 4))
|
715 |
+
>>> ax.plot(y[:, 0], y[:, 1], 'o', label='data')
|
716 |
+
>>> ax.plot(np.cos(xs), np.sin(xs), label='true')
|
717 |
+
>>> ax.plot(cs(xs)[:, 0], cs(xs)[:, 1], label='spline')
|
718 |
+
>>> ax.axes.set_aspect('equal')
|
719 |
+
>>> ax.legend(loc='center')
|
720 |
+
>>> plt.show()
|
721 |
+
|
722 |
+
The third example is the interpolation of a polynomial y = x**3 on the
|
723 |
+
interval 0 <= x<= 1. A cubic spline can represent this function exactly.
|
724 |
+
To achieve that we need to specify values and first derivatives at
|
725 |
+
endpoints of the interval. Note that y' = 3 * x**2 and thus y'(0) = 0 and
|
726 |
+
y'(1) = 3.
|
727 |
+
|
728 |
+
>>> cs = CubicSpline([0, 1], [0, 1], bc_type=((1, 0), (1, 3)))
|
729 |
+
>>> x = np.linspace(0, 1)
|
730 |
+
>>> np.allclose(x**3, cs(x))
|
731 |
+
True
|
732 |
+
|
733 |
+
References
|
734 |
+
----------
|
735 |
+
.. [1] `Cubic Spline Interpolation
|
736 |
+
<https://en.wikiversity.org/wiki/Cubic_Spline_Interpolation>`_
|
737 |
+
on Wikiversity.
|
738 |
+
.. [2] Carl de Boor, "A Practical Guide to Splines", Springer-Verlag, 1978.
|
739 |
+
"""
|
740 |
+
|
741 |
+
def __init__(self, x, y, axis=0, bc_type='not-a-knot', extrapolate=None):
|
742 |
+
x, dx, y, axis, _ = prepare_input(x, y, axis)
|
743 |
+
n = len(x)
|
744 |
+
|
745 |
+
bc, y = self._validate_bc(bc_type, y, y.shape[1:], axis)
|
746 |
+
|
747 |
+
if extrapolate is None:
|
748 |
+
if bc[0] == 'periodic':
|
749 |
+
extrapolate = 'periodic'
|
750 |
+
else:
|
751 |
+
extrapolate = True
|
752 |
+
|
753 |
+
if y.size == 0:
|
754 |
+
# bail out early for zero-sized arrays
|
755 |
+
s = np.zeros_like(y)
|
756 |
+
else:
|
757 |
+
dxr = dx.reshape([dx.shape[0]] + [1] * (y.ndim - 1))
|
758 |
+
slope = np.diff(y, axis=0) / dxr
|
759 |
+
|
760 |
+
# If bc is 'not-a-knot' this change is just a convention.
|
761 |
+
# If bc is 'periodic' then we already checked that y[0] == y[-1],
|
762 |
+
# and the spline is just a constant, we handle this case in the
|
763 |
+
# same way by setting the first derivatives to slope, which is 0.
|
764 |
+
if n == 2:
|
765 |
+
if bc[0] in ['not-a-knot', 'periodic']:
|
766 |
+
bc[0] = (1, slope[0])
|
767 |
+
if bc[1] in ['not-a-knot', 'periodic']:
|
768 |
+
bc[1] = (1, slope[0])
|
769 |
+
|
770 |
+
# This is a special case, when both conditions are 'not-a-knot'
|
771 |
+
# and n == 3. In this case 'not-a-knot' can't be handled regularly
|
772 |
+
# as the both conditions are identical. We handle this case by
|
773 |
+
# constructing a parabola passing through given points.
|
774 |
+
if n == 3 and bc[0] == 'not-a-knot' and bc[1] == 'not-a-knot':
|
775 |
+
A = np.zeros((3, 3)) # This is a standard matrix.
|
776 |
+
b = np.empty((3,) + y.shape[1:], dtype=y.dtype)
|
777 |
+
|
778 |
+
A[0, 0] = 1
|
779 |
+
A[0, 1] = 1
|
780 |
+
A[1, 0] = dx[1]
|
781 |
+
A[1, 1] = 2 * (dx[0] + dx[1])
|
782 |
+
A[1, 2] = dx[0]
|
783 |
+
A[2, 1] = 1
|
784 |
+
A[2, 2] = 1
|
785 |
+
|
786 |
+
b[0] = 2 * slope[0]
|
787 |
+
b[1] = 3 * (dxr[0] * slope[1] + dxr[1] * slope[0])
|
788 |
+
b[2] = 2 * slope[1]
|
789 |
+
|
790 |
+
s = solve(A, b, overwrite_a=True, overwrite_b=True,
|
791 |
+
check_finite=False)
|
792 |
+
elif n == 3 and bc[0] == 'periodic':
|
793 |
+
# In case when number of points is 3 we compute the derivatives
|
794 |
+
# manually
|
795 |
+
t = (slope / dxr).sum(0) / (1. / dxr).sum(0)
|
796 |
+
s = np.broadcast_to(t, (n,) + y.shape[1:])
|
797 |
+
else:
|
798 |
+
# Find derivative values at each x[i] by solving a tridiagonal
|
799 |
+
# system.
|
800 |
+
A = np.zeros((3, n)) # This is a banded matrix representation.
|
801 |
+
b = np.empty((n,) + y.shape[1:], dtype=y.dtype)
|
802 |
+
|
803 |
+
# Filling the system for i=1..n-2
|
804 |
+
# (x[i-1] - x[i]) * s[i-1] +\
|
805 |
+
# 2 * ((x[i] - x[i-1]) + (x[i+1] - x[i])) * s[i] +\
|
806 |
+
# (x[i] - x[i-1]) * s[i+1] =\
|
807 |
+
# 3 * ((x[i+1] - x[i])*(y[i] - y[i-1])/(x[i] - x[i-1]) +\
|
808 |
+
# (x[i] - x[i-1])*(y[i+1] - y[i])/(x[i+1] - x[i]))
|
809 |
+
|
810 |
+
A[1, 1:-1] = 2 * (dx[:-1] + dx[1:]) # The diagonal
|
811 |
+
A[0, 2:] = dx[:-1] # The upper diagonal
|
812 |
+
A[-1, :-2] = dx[1:] # The lower diagonal
|
813 |
+
|
814 |
+
b[1:-1] = 3 * (dxr[1:] * slope[:-1] + dxr[:-1] * slope[1:])
|
815 |
+
|
816 |
+
bc_start, bc_end = bc
|
817 |
+
|
818 |
+
if bc_start == 'periodic':
|
819 |
+
# Due to the periodicity, and because y[-1] = y[0], the
|
820 |
+
# linear system has (n-1) unknowns/equations instead of n:
|
821 |
+
A = A[:, 0:-1]
|
822 |
+
A[1, 0] = 2 * (dx[-1] + dx[0])
|
823 |
+
A[0, 1] = dx[-1]
|
824 |
+
|
825 |
+
b = b[:-1]
|
826 |
+
|
827 |
+
# Also, due to the periodicity, the system is not tri-diagonal.
|
828 |
+
# We need to compute a "condensed" matrix of shape (n-2, n-2).
|
829 |
+
# See https://web.archive.org/web/20151220180652/http://www.cfm.brown.edu/people/gk/chap6/node14.html
|
830 |
+
# for more explanations.
|
831 |
+
# The condensed matrix is obtained by removing the last column
|
832 |
+
# and last row of the (n-1, n-1) system matrix. The removed
|
833 |
+
# values are saved in scalar variables with the (n-1, n-1)
|
834 |
+
# system matrix indices forming their names:
|
835 |
+
a_m1_0 = dx[-2] # lower left corner value: A[-1, 0]
|
836 |
+
a_m1_m2 = dx[-1]
|
837 |
+
a_m1_m1 = 2 * (dx[-1] + dx[-2])
|
838 |
+
a_m2_m1 = dx[-3]
|
839 |
+
a_0_m1 = dx[0]
|
840 |
+
|
841 |
+
b[0] = 3 * (dxr[0] * slope[-1] + dxr[-1] * slope[0])
|
842 |
+
b[-1] = 3 * (dxr[-1] * slope[-2] + dxr[-2] * slope[-1])
|
843 |
+
|
844 |
+
Ac = A[:, :-1]
|
845 |
+
b1 = b[:-1]
|
846 |
+
b2 = np.zeros_like(b1)
|
847 |
+
b2[0] = -a_0_m1
|
848 |
+
b2[-1] = -a_m2_m1
|
849 |
+
|
850 |
+
# s1 and s2 are the solutions of (n-2, n-2) system
|
851 |
+
s1 = solve_banded((1, 1), Ac, b1, overwrite_ab=False,
|
852 |
+
overwrite_b=False, check_finite=False)
|
853 |
+
|
854 |
+
s2 = solve_banded((1, 1), Ac, b2, overwrite_ab=False,
|
855 |
+
overwrite_b=False, check_finite=False)
|
856 |
+
|
857 |
+
# computing the s[n-2] solution:
|
858 |
+
s_m1 = ((b[-1] - a_m1_0 * s1[0] - a_m1_m2 * s1[-1]) /
|
859 |
+
(a_m1_m1 + a_m1_0 * s2[0] + a_m1_m2 * s2[-1]))
|
860 |
+
|
861 |
+
# s is the solution of the (n, n) system:
|
862 |
+
s = np.empty((n,) + y.shape[1:], dtype=y.dtype)
|
863 |
+
s[:-2] = s1 + s_m1 * s2
|
864 |
+
s[-2] = s_m1
|
865 |
+
s[-1] = s[0]
|
866 |
+
else:
|
867 |
+
if bc_start == 'not-a-knot':
|
868 |
+
A[1, 0] = dx[1]
|
869 |
+
A[0, 1] = x[2] - x[0]
|
870 |
+
d = x[2] - x[0]
|
871 |
+
b[0] = ((dxr[0] + 2*d) * dxr[1] * slope[0] +
|
872 |
+
dxr[0]**2 * slope[1]) / d
|
873 |
+
elif bc_start[0] == 1:
|
874 |
+
A[1, 0] = 1
|
875 |
+
A[0, 1] = 0
|
876 |
+
b[0] = bc_start[1]
|
877 |
+
elif bc_start[0] == 2:
|
878 |
+
A[1, 0] = 2 * dx[0]
|
879 |
+
A[0, 1] = dx[0]
|
880 |
+
b[0] = -0.5 * bc_start[1] * dx[0]**2 + 3 * (y[1] - y[0])
|
881 |
+
|
882 |
+
if bc_end == 'not-a-knot':
|
883 |
+
A[1, -1] = dx[-2]
|
884 |
+
A[-1, -2] = x[-1] - x[-3]
|
885 |
+
d = x[-1] - x[-3]
|
886 |
+
b[-1] = ((dxr[-1]**2*slope[-2] +
|
887 |
+
(2*d + dxr[-1])*dxr[-2]*slope[-1]) / d)
|
888 |
+
elif bc_end[0] == 1:
|
889 |
+
A[1, -1] = 1
|
890 |
+
A[-1, -2] = 0
|
891 |
+
b[-1] = bc_end[1]
|
892 |
+
elif bc_end[0] == 2:
|
893 |
+
A[1, -1] = 2 * dx[-1]
|
894 |
+
A[-1, -2] = dx[-1]
|
895 |
+
b[-1] = 0.5 * bc_end[1] * dx[-1]**2 + 3 * (y[-1] - y[-2])
|
896 |
+
|
897 |
+
s = solve_banded((1, 1), A, b, overwrite_ab=True,
|
898 |
+
overwrite_b=True, check_finite=False)
|
899 |
+
|
900 |
+
super().__init__(x, y, s, axis=0, extrapolate=extrapolate)
|
901 |
+
self.axis = axis
|
902 |
+
|
903 |
+
@staticmethod
|
904 |
+
def _validate_bc(bc_type, y, expected_deriv_shape, axis):
|
905 |
+
"""Validate and prepare boundary conditions.
|
906 |
+
|
907 |
+
Returns
|
908 |
+
-------
|
909 |
+
validated_bc : 2-tuple
|
910 |
+
Boundary conditions for a curve start and end.
|
911 |
+
y : ndarray
|
912 |
+
y casted to complex dtype if one of the boundary conditions has
|
913 |
+
complex dtype.
|
914 |
+
"""
|
915 |
+
if isinstance(bc_type, str):
|
916 |
+
if bc_type == 'periodic':
|
917 |
+
if not np.allclose(y[0], y[-1], rtol=1e-15, atol=1e-15):
|
918 |
+
raise ValueError(
|
919 |
+
f"The first and last `y` point along axis {axis} must "
|
920 |
+
"be identical (within machine precision) when "
|
921 |
+
"bc_type='periodic'.")
|
922 |
+
|
923 |
+
bc_type = (bc_type, bc_type)
|
924 |
+
|
925 |
+
else:
|
926 |
+
if len(bc_type) != 2:
|
927 |
+
raise ValueError("`bc_type` must contain 2 elements to "
|
928 |
+
"specify start and end conditions.")
|
929 |
+
|
930 |
+
if 'periodic' in bc_type:
|
931 |
+
raise ValueError("'periodic' `bc_type` is defined for both "
|
932 |
+
"curve ends and cannot be used with other "
|
933 |
+
"boundary conditions.")
|
934 |
+
|
935 |
+
validated_bc = []
|
936 |
+
for bc in bc_type:
|
937 |
+
if isinstance(bc, str):
|
938 |
+
if bc == 'clamped':
|
939 |
+
validated_bc.append((1, np.zeros(expected_deriv_shape)))
|
940 |
+
elif bc == 'natural':
|
941 |
+
validated_bc.append((2, np.zeros(expected_deriv_shape)))
|
942 |
+
elif bc in ['not-a-knot', 'periodic']:
|
943 |
+
validated_bc.append(bc)
|
944 |
+
else:
|
945 |
+
raise ValueError(f"bc_type={bc} is not allowed.")
|
946 |
+
else:
|
947 |
+
try:
|
948 |
+
deriv_order, deriv_value = bc
|
949 |
+
except Exception as e:
|
950 |
+
raise ValueError(
|
951 |
+
"A specified derivative value must be "
|
952 |
+
"given in the form (order, value)."
|
953 |
+
) from e
|
954 |
+
|
955 |
+
if deriv_order not in [1, 2]:
|
956 |
+
raise ValueError("The specified derivative order must "
|
957 |
+
"be 1 or 2.")
|
958 |
+
|
959 |
+
deriv_value = np.asarray(deriv_value)
|
960 |
+
if deriv_value.shape != expected_deriv_shape:
|
961 |
+
raise ValueError(
|
962 |
+
"`deriv_value` shape {} is not the expected one {}."
|
963 |
+
.format(deriv_value.shape, expected_deriv_shape))
|
964 |
+
|
965 |
+
if np.issubdtype(deriv_value.dtype, np.complexfloating):
|
966 |
+
y = y.astype(complex, copy=False)
|
967 |
+
|
968 |
+
validated_bc.append((deriv_order, deriv_value))
|
969 |
+
|
970 |
+
return validated_bc, y
|
env-llmeval/lib/python3.10/site-packages/scipy/interpolate/_fitpack.cpython-310-x86_64-linux-gnu.so
ADDED
Binary file (91.4 kB). View file
|
|
env-llmeval/lib/python3.10/site-packages/scipy/interpolate/_fitpack_impl.py
ADDED
@@ -0,0 +1,805 @@
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|
1 |
+
"""
|
2 |
+
fitpack (dierckx in netlib) --- A Python-C wrapper to FITPACK (by P. Dierckx).
|
3 |
+
FITPACK is a collection of FORTRAN programs for curve and surface
|
4 |
+
fitting with splines and tensor product splines.
|
5 |
+
|
6 |
+
See
|
7 |
+
https://web.archive.org/web/20010524124604/http://www.cs.kuleuven.ac.be:80/cwis/research/nalag/research/topics/fitpack.html
|
8 |
+
or
|
9 |
+
http://www.netlib.org/dierckx/
|
10 |
+
|
11 |
+
Copyright 2002 Pearu Peterson all rights reserved,
|
12 |
+
Pearu Peterson <[email protected]>
|
13 |
+
Permission to use, modify, and distribute this software is given under the
|
14 |
+
terms of the SciPy (BSD style) license. See LICENSE.txt that came with
|
15 |
+
this distribution for specifics.
|
16 |
+
|
17 |
+
NO WARRANTY IS EXPRESSED OR IMPLIED. USE AT YOUR OWN RISK.
|
18 |
+
|
19 |
+
TODO: Make interfaces to the following fitpack functions:
|
20 |
+
For univariate splines: cocosp, concon, fourco, insert
|
21 |
+
For bivariate splines: profil, regrid, parsur, surev
|
22 |
+
"""
|
23 |
+
|
24 |
+
__all__ = ['splrep', 'splprep', 'splev', 'splint', 'sproot', 'spalde',
|
25 |
+
'bisplrep', 'bisplev', 'insert', 'splder', 'splantider']
|
26 |
+
|
27 |
+
import warnings
|
28 |
+
import numpy as np
|
29 |
+
from . import _fitpack
|
30 |
+
from numpy import (atleast_1d, array, ones, zeros, sqrt, ravel, transpose,
|
31 |
+
empty, iinfo, asarray)
|
32 |
+
|
33 |
+
# Try to replace _fitpack interface with
|
34 |
+
# f2py-generated version
|
35 |
+
from . import dfitpack
|
36 |
+
|
37 |
+
|
38 |
+
dfitpack_int = dfitpack.types.intvar.dtype
|
39 |
+
|
40 |
+
|
41 |
+
def _int_overflow(x, exception, msg=None):
|
42 |
+
"""Cast the value to an dfitpack_int and raise an OverflowError if the value
|
43 |
+
cannot fit.
|
44 |
+
"""
|
45 |
+
if x > iinfo(dfitpack_int).max:
|
46 |
+
if msg is None:
|
47 |
+
msg = f'{x!r} cannot fit into an {dfitpack_int!r}'
|
48 |
+
raise exception(msg)
|
49 |
+
return dfitpack_int.type(x)
|
50 |
+
|
51 |
+
|
52 |
+
_iermess = {
|
53 |
+
0: ["The spline has a residual sum of squares fp such that "
|
54 |
+
"abs(fp-s)/s<=0.001", None],
|
55 |
+
-1: ["The spline is an interpolating spline (fp=0)", None],
|
56 |
+
-2: ["The spline is weighted least-squares polynomial of degree k.\n"
|
57 |
+
"fp gives the upper bound fp0 for the smoothing factor s", None],
|
58 |
+
1: ["The required storage space exceeds the available storage space.\n"
|
59 |
+
"Probable causes: data (x,y) size is too small or smoothing parameter"
|
60 |
+
"\ns is too small (fp>s).", ValueError],
|
61 |
+
2: ["A theoretically impossible result when finding a smoothing spline\n"
|
62 |
+
"with fp = s. Probable cause: s too small. (abs(fp-s)/s>0.001)",
|
63 |
+
ValueError],
|
64 |
+
3: ["The maximal number of iterations (20) allowed for finding smoothing\n"
|
65 |
+
"spline with fp=s has been reached. Probable cause: s too small.\n"
|
66 |
+
"(abs(fp-s)/s>0.001)", ValueError],
|
67 |
+
10: ["Error on input data", ValueError],
|
68 |
+
'unknown': ["An error occurred", TypeError]
|
69 |
+
}
|
70 |
+
|
71 |
+
_iermess2 = {
|
72 |
+
0: ["The spline has a residual sum of squares fp such that "
|
73 |
+
"abs(fp-s)/s<=0.001", None],
|
74 |
+
-1: ["The spline is an interpolating spline (fp=0)", None],
|
75 |
+
-2: ["The spline is weighted least-squares polynomial of degree kx and ky."
|
76 |
+
"\nfp gives the upper bound fp0 for the smoothing factor s", None],
|
77 |
+
-3: ["Warning. The coefficients of the spline have been computed as the\n"
|
78 |
+
"minimal norm least-squares solution of a rank deficient system.",
|
79 |
+
None],
|
80 |
+
1: ["The required storage space exceeds the available storage space.\n"
|
81 |
+
"Probable causes: nxest or nyest too small or s is too small. (fp>s)",
|
82 |
+
ValueError],
|
83 |
+
2: ["A theoretically impossible result when finding a smoothing spline\n"
|
84 |
+
"with fp = s. Probable causes: s too small or badly chosen eps.\n"
|
85 |
+
"(abs(fp-s)/s>0.001)", ValueError],
|
86 |
+
3: ["The maximal number of iterations (20) allowed for finding smoothing\n"
|
87 |
+
"spline with fp=s has been reached. Probable cause: s too small.\n"
|
88 |
+
"(abs(fp-s)/s>0.001)", ValueError],
|
89 |
+
4: ["No more knots can be added because the number of B-spline\n"
|
90 |
+
"coefficients already exceeds the number of data points m.\n"
|
91 |
+
"Probable causes: either s or m too small. (fp>s)", ValueError],
|
92 |
+
5: ["No more knots can be added because the additional knot would\n"
|
93 |
+
"coincide with an old one. Probable cause: s too small or too large\n"
|
94 |
+
"a weight to an inaccurate data point. (fp>s)", ValueError],
|
95 |
+
10: ["Error on input data", ValueError],
|
96 |
+
11: ["rwrk2 too small, i.e., there is not enough workspace for computing\n"
|
97 |
+
"the minimal least-squares solution of a rank deficient system of\n"
|
98 |
+
"linear equations.", ValueError],
|
99 |
+
'unknown': ["An error occurred", TypeError]
|
100 |
+
}
|
101 |
+
|
102 |
+
_parcur_cache = {'t': array([], float), 'wrk': array([], float),
|
103 |
+
'iwrk': array([], dfitpack_int), 'u': array([], float),
|
104 |
+
'ub': 0, 'ue': 1}
|
105 |
+
|
106 |
+
|
107 |
+
def splprep(x, w=None, u=None, ub=None, ue=None, k=3, task=0, s=None, t=None,
|
108 |
+
full_output=0, nest=None, per=0, quiet=1):
|
109 |
+
# see the docstring of `_fitpack_py/splprep`
|
110 |
+
if task <= 0:
|
111 |
+
_parcur_cache = {'t': array([], float), 'wrk': array([], float),
|
112 |
+
'iwrk': array([], dfitpack_int), 'u': array([], float),
|
113 |
+
'ub': 0, 'ue': 1}
|
114 |
+
x = atleast_1d(x)
|
115 |
+
idim, m = x.shape
|
116 |
+
if per:
|
117 |
+
for i in range(idim):
|
118 |
+
if x[i][0] != x[i][-1]:
|
119 |
+
if not quiet:
|
120 |
+
warnings.warn(RuntimeWarning('Setting x[%d][%d]=x[%d][0]' %
|
121 |
+
(i, m, i)),
|
122 |
+
stacklevel=2)
|
123 |
+
x[i][-1] = x[i][0]
|
124 |
+
if not 0 < idim < 11:
|
125 |
+
raise TypeError('0 < idim < 11 must hold')
|
126 |
+
if w is None:
|
127 |
+
w = ones(m, float)
|
128 |
+
else:
|
129 |
+
w = atleast_1d(w)
|
130 |
+
ipar = (u is not None)
|
131 |
+
if ipar:
|
132 |
+
_parcur_cache['u'] = u
|
133 |
+
if ub is None:
|
134 |
+
_parcur_cache['ub'] = u[0]
|
135 |
+
else:
|
136 |
+
_parcur_cache['ub'] = ub
|
137 |
+
if ue is None:
|
138 |
+
_parcur_cache['ue'] = u[-1]
|
139 |
+
else:
|
140 |
+
_parcur_cache['ue'] = ue
|
141 |
+
else:
|
142 |
+
_parcur_cache['u'] = zeros(m, float)
|
143 |
+
if not (1 <= k <= 5):
|
144 |
+
raise TypeError('1 <= k= %d <=5 must hold' % k)
|
145 |
+
if not (-1 <= task <= 1):
|
146 |
+
raise TypeError('task must be -1, 0 or 1')
|
147 |
+
if (not len(w) == m) or (ipar == 1 and (not len(u) == m)):
|
148 |
+
raise TypeError('Mismatch of input dimensions')
|
149 |
+
if s is None:
|
150 |
+
s = m - sqrt(2*m)
|
151 |
+
if t is None and task == -1:
|
152 |
+
raise TypeError('Knots must be given for task=-1')
|
153 |
+
if t is not None:
|
154 |
+
_parcur_cache['t'] = atleast_1d(t)
|
155 |
+
n = len(_parcur_cache['t'])
|
156 |
+
if task == -1 and n < 2*k + 2:
|
157 |
+
raise TypeError('There must be at least 2*k+2 knots for task=-1')
|
158 |
+
if m <= k:
|
159 |
+
raise TypeError('m > k must hold')
|
160 |
+
if nest is None:
|
161 |
+
nest = m + 2*k
|
162 |
+
|
163 |
+
if (task >= 0 and s == 0) or (nest < 0):
|
164 |
+
if per:
|
165 |
+
nest = m + 2*k
|
166 |
+
else:
|
167 |
+
nest = m + k + 1
|
168 |
+
nest = max(nest, 2*k + 3)
|
169 |
+
u = _parcur_cache['u']
|
170 |
+
ub = _parcur_cache['ub']
|
171 |
+
ue = _parcur_cache['ue']
|
172 |
+
t = _parcur_cache['t']
|
173 |
+
wrk = _parcur_cache['wrk']
|
174 |
+
iwrk = _parcur_cache['iwrk']
|
175 |
+
t, c, o = _fitpack._parcur(ravel(transpose(x)), w, u, ub, ue, k,
|
176 |
+
task, ipar, s, t, nest, wrk, iwrk, per)
|
177 |
+
_parcur_cache['u'] = o['u']
|
178 |
+
_parcur_cache['ub'] = o['ub']
|
179 |
+
_parcur_cache['ue'] = o['ue']
|
180 |
+
_parcur_cache['t'] = t
|
181 |
+
_parcur_cache['wrk'] = o['wrk']
|
182 |
+
_parcur_cache['iwrk'] = o['iwrk']
|
183 |
+
ier = o['ier']
|
184 |
+
fp = o['fp']
|
185 |
+
n = len(t)
|
186 |
+
u = o['u']
|
187 |
+
c.shape = idim, n - k - 1
|
188 |
+
tcku = [t, list(c), k], u
|
189 |
+
if ier <= 0 and not quiet:
|
190 |
+
warnings.warn(RuntimeWarning(_iermess[ier][0] +
|
191 |
+
"\tk=%d n=%d m=%d fp=%f s=%f" %
|
192 |
+
(k, len(t), m, fp, s)),
|
193 |
+
stacklevel=2)
|
194 |
+
if ier > 0 and not full_output:
|
195 |
+
if ier in [1, 2, 3]:
|
196 |
+
warnings.warn(RuntimeWarning(_iermess[ier][0]), stacklevel=2)
|
197 |
+
else:
|
198 |
+
try:
|
199 |
+
raise _iermess[ier][1](_iermess[ier][0])
|
200 |
+
except KeyError as e:
|
201 |
+
raise _iermess['unknown'][1](_iermess['unknown'][0]) from e
|
202 |
+
if full_output:
|
203 |
+
try:
|
204 |
+
return tcku, fp, ier, _iermess[ier][0]
|
205 |
+
except KeyError:
|
206 |
+
return tcku, fp, ier, _iermess['unknown'][0]
|
207 |
+
else:
|
208 |
+
return tcku
|
209 |
+
|
210 |
+
|
211 |
+
_curfit_cache = {'t': array([], float), 'wrk': array([], float),
|
212 |
+
'iwrk': array([], dfitpack_int)}
|
213 |
+
|
214 |
+
|
215 |
+
def splrep(x, y, w=None, xb=None, xe=None, k=3, task=0, s=None, t=None,
|
216 |
+
full_output=0, per=0, quiet=1):
|
217 |
+
# see the docstring of `_fitpack_py/splrep`
|
218 |
+
if task <= 0:
|
219 |
+
_curfit_cache = {}
|
220 |
+
x, y = map(atleast_1d, [x, y])
|
221 |
+
m = len(x)
|
222 |
+
if w is None:
|
223 |
+
w = ones(m, float)
|
224 |
+
if s is None:
|
225 |
+
s = 0.0
|
226 |
+
else:
|
227 |
+
w = atleast_1d(w)
|
228 |
+
if s is None:
|
229 |
+
s = m - sqrt(2*m)
|
230 |
+
if not len(w) == m:
|
231 |
+
raise TypeError('len(w)=%d is not equal to m=%d' % (len(w), m))
|
232 |
+
if (m != len(y)) or (m != len(w)):
|
233 |
+
raise TypeError('Lengths of the first three arguments (x,y,w) must '
|
234 |
+
'be equal')
|
235 |
+
if not (1 <= k <= 5):
|
236 |
+
raise TypeError('Given degree of the spline (k=%d) is not supported. '
|
237 |
+
'(1<=k<=5)' % k)
|
238 |
+
if m <= k:
|
239 |
+
raise TypeError('m > k must hold')
|
240 |
+
if xb is None:
|
241 |
+
xb = x[0]
|
242 |
+
if xe is None:
|
243 |
+
xe = x[-1]
|
244 |
+
if not (-1 <= task <= 1):
|
245 |
+
raise TypeError('task must be -1, 0 or 1')
|
246 |
+
if t is not None:
|
247 |
+
task = -1
|
248 |
+
if task == -1:
|
249 |
+
if t is None:
|
250 |
+
raise TypeError('Knots must be given for task=-1')
|
251 |
+
numknots = len(t)
|
252 |
+
_curfit_cache['t'] = empty((numknots + 2*k + 2,), float)
|
253 |
+
_curfit_cache['t'][k+1:-k-1] = t
|
254 |
+
nest = len(_curfit_cache['t'])
|
255 |
+
elif task == 0:
|
256 |
+
if per:
|
257 |
+
nest = max(m + 2*k, 2*k + 3)
|
258 |
+
else:
|
259 |
+
nest = max(m + k + 1, 2*k + 3)
|
260 |
+
t = empty((nest,), float)
|
261 |
+
_curfit_cache['t'] = t
|
262 |
+
if task <= 0:
|
263 |
+
if per:
|
264 |
+
_curfit_cache['wrk'] = empty((m*(k + 1) + nest*(8 + 5*k),), float)
|
265 |
+
else:
|
266 |
+
_curfit_cache['wrk'] = empty((m*(k + 1) + nest*(7 + 3*k),), float)
|
267 |
+
_curfit_cache['iwrk'] = empty((nest,), dfitpack_int)
|
268 |
+
try:
|
269 |
+
t = _curfit_cache['t']
|
270 |
+
wrk = _curfit_cache['wrk']
|
271 |
+
iwrk = _curfit_cache['iwrk']
|
272 |
+
except KeyError as e:
|
273 |
+
raise TypeError("must call with task=1 only after"
|
274 |
+
" call with task=0,-1") from e
|
275 |
+
if not per:
|
276 |
+
n, c, fp, ier = dfitpack.curfit(task, x, y, w, t, wrk, iwrk,
|
277 |
+
xb, xe, k, s)
|
278 |
+
else:
|
279 |
+
n, c, fp, ier = dfitpack.percur(task, x, y, w, t, wrk, iwrk, k, s)
|
280 |
+
tck = (t[:n], c[:n], k)
|
281 |
+
if ier <= 0 and not quiet:
|
282 |
+
_mess = (_iermess[ier][0] + "\tk=%d n=%d m=%d fp=%f s=%f" %
|
283 |
+
(k, len(t), m, fp, s))
|
284 |
+
warnings.warn(RuntimeWarning(_mess), stacklevel=2)
|
285 |
+
if ier > 0 and not full_output:
|
286 |
+
if ier in [1, 2, 3]:
|
287 |
+
warnings.warn(RuntimeWarning(_iermess[ier][0]), stacklevel=2)
|
288 |
+
else:
|
289 |
+
try:
|
290 |
+
raise _iermess[ier][1](_iermess[ier][0])
|
291 |
+
except KeyError as e:
|
292 |
+
raise _iermess['unknown'][1](_iermess['unknown'][0]) from e
|
293 |
+
if full_output:
|
294 |
+
try:
|
295 |
+
return tck, fp, ier, _iermess[ier][0]
|
296 |
+
except KeyError:
|
297 |
+
return tck, fp, ier, _iermess['unknown'][0]
|
298 |
+
else:
|
299 |
+
return tck
|
300 |
+
|
301 |
+
|
302 |
+
def splev(x, tck, der=0, ext=0):
|
303 |
+
# see the docstring of `_fitpack_py/splev`
|
304 |
+
t, c, k = tck
|
305 |
+
try:
|
306 |
+
c[0][0]
|
307 |
+
parametric = True
|
308 |
+
except Exception:
|
309 |
+
parametric = False
|
310 |
+
if parametric:
|
311 |
+
return list(map(lambda c, x=x, t=t, k=k, der=der:
|
312 |
+
splev(x, [t, c, k], der, ext), c))
|
313 |
+
else:
|
314 |
+
if not (0 <= der <= k):
|
315 |
+
raise ValueError("0<=der=%d<=k=%d must hold" % (der, k))
|
316 |
+
if ext not in (0, 1, 2, 3):
|
317 |
+
raise ValueError("ext = %s not in (0, 1, 2, 3) " % ext)
|
318 |
+
|
319 |
+
x = asarray(x)
|
320 |
+
shape = x.shape
|
321 |
+
x = atleast_1d(x).ravel()
|
322 |
+
if der == 0:
|
323 |
+
y, ier = dfitpack.splev(t, c, k, x, ext)
|
324 |
+
else:
|
325 |
+
y, ier = dfitpack.splder(t, c, k, x, der, ext)
|
326 |
+
|
327 |
+
if ier == 10:
|
328 |
+
raise ValueError("Invalid input data")
|
329 |
+
if ier == 1:
|
330 |
+
raise ValueError("Found x value not in the domain")
|
331 |
+
if ier:
|
332 |
+
raise TypeError("An error occurred")
|
333 |
+
|
334 |
+
return y.reshape(shape)
|
335 |
+
|
336 |
+
|
337 |
+
def splint(a, b, tck, full_output=0):
|
338 |
+
# see the docstring of `_fitpack_py/splint`
|
339 |
+
t, c, k = tck
|
340 |
+
try:
|
341 |
+
c[0][0]
|
342 |
+
parametric = True
|
343 |
+
except Exception:
|
344 |
+
parametric = False
|
345 |
+
if parametric:
|
346 |
+
return list(map(lambda c, a=a, b=b, t=t, k=k:
|
347 |
+
splint(a, b, [t, c, k]), c))
|
348 |
+
else:
|
349 |
+
aint, wrk = dfitpack.splint(t, c, k, a, b)
|
350 |
+
if full_output:
|
351 |
+
return aint, wrk
|
352 |
+
else:
|
353 |
+
return aint
|
354 |
+
|
355 |
+
|
356 |
+
def sproot(tck, mest=10):
|
357 |
+
# see the docstring of `_fitpack_py/sproot`
|
358 |
+
t, c, k = tck
|
359 |
+
if k != 3:
|
360 |
+
raise ValueError("sproot works only for cubic (k=3) splines")
|
361 |
+
try:
|
362 |
+
c[0][0]
|
363 |
+
parametric = True
|
364 |
+
except Exception:
|
365 |
+
parametric = False
|
366 |
+
if parametric:
|
367 |
+
return list(map(lambda c, t=t, k=k, mest=mest:
|
368 |
+
sproot([t, c, k], mest), c))
|
369 |
+
else:
|
370 |
+
if len(t) < 8:
|
371 |
+
raise TypeError("The number of knots %d>=8" % len(t))
|
372 |
+
z, m, ier = dfitpack.sproot(t, c, mest)
|
373 |
+
if ier == 10:
|
374 |
+
raise TypeError("Invalid input data. "
|
375 |
+
"t1<=..<=t4<t5<..<tn-3<=..<=tn must hold.")
|
376 |
+
if ier == 0:
|
377 |
+
return z[:m]
|
378 |
+
if ier == 1:
|
379 |
+
warnings.warn(RuntimeWarning("The number of zeros exceeds mest"),
|
380 |
+
stacklevel=2)
|
381 |
+
return z[:m]
|
382 |
+
raise TypeError("Unknown error")
|
383 |
+
|
384 |
+
|
385 |
+
def spalde(x, tck):
|
386 |
+
# see the docstring of `_fitpack_py/spalde`
|
387 |
+
t, c, k = tck
|
388 |
+
try:
|
389 |
+
c[0][0]
|
390 |
+
parametric = True
|
391 |
+
except Exception:
|
392 |
+
parametric = False
|
393 |
+
if parametric:
|
394 |
+
return list(map(lambda c, x=x, t=t, k=k:
|
395 |
+
spalde(x, [t, c, k]), c))
|
396 |
+
else:
|
397 |
+
x = atleast_1d(x)
|
398 |
+
if len(x) > 1:
|
399 |
+
return list(map(lambda x, tck=tck: spalde(x, tck), x))
|
400 |
+
d, ier = dfitpack.spalde(t, c, k+1, x[0])
|
401 |
+
if ier == 0:
|
402 |
+
return d
|
403 |
+
if ier == 10:
|
404 |
+
raise TypeError("Invalid input data. t(k)<=x<=t(n-k+1) must hold.")
|
405 |
+
raise TypeError("Unknown error")
|
406 |
+
|
407 |
+
# def _curfit(x,y,w=None,xb=None,xe=None,k=3,task=0,s=None,t=None,
|
408 |
+
# full_output=0,nest=None,per=0,quiet=1):
|
409 |
+
|
410 |
+
|
411 |
+
_surfit_cache = {'tx': array([], float), 'ty': array([], float),
|
412 |
+
'wrk': array([], float), 'iwrk': array([], dfitpack_int)}
|
413 |
+
|
414 |
+
|
415 |
+
def bisplrep(x, y, z, w=None, xb=None, xe=None, yb=None, ye=None,
|
416 |
+
kx=3, ky=3, task=0, s=None, eps=1e-16, tx=None, ty=None,
|
417 |
+
full_output=0, nxest=None, nyest=None, quiet=1):
|
418 |
+
"""
|
419 |
+
Find a bivariate B-spline representation of a surface.
|
420 |
+
|
421 |
+
Given a set of data points (x[i], y[i], z[i]) representing a surface
|
422 |
+
z=f(x,y), compute a B-spline representation of the surface. Based on
|
423 |
+
the routine SURFIT from FITPACK.
|
424 |
+
|
425 |
+
Parameters
|
426 |
+
----------
|
427 |
+
x, y, z : ndarray
|
428 |
+
Rank-1 arrays of data points.
|
429 |
+
w : ndarray, optional
|
430 |
+
Rank-1 array of weights. By default ``w=np.ones(len(x))``.
|
431 |
+
xb, xe : float, optional
|
432 |
+
End points of approximation interval in `x`.
|
433 |
+
By default ``xb = x.min(), xe=x.max()``.
|
434 |
+
yb, ye : float, optional
|
435 |
+
End points of approximation interval in `y`.
|
436 |
+
By default ``yb=y.min(), ye = y.max()``.
|
437 |
+
kx, ky : int, optional
|
438 |
+
The degrees of the spline (1 <= kx, ky <= 5).
|
439 |
+
Third order (kx=ky=3) is recommended.
|
440 |
+
task : int, optional
|
441 |
+
If task=0, find knots in x and y and coefficients for a given
|
442 |
+
smoothing factor, s.
|
443 |
+
If task=1, find knots and coefficients for another value of the
|
444 |
+
smoothing factor, s. bisplrep must have been previously called
|
445 |
+
with task=0 or task=1.
|
446 |
+
If task=-1, find coefficients for a given set of knots tx, ty.
|
447 |
+
s : float, optional
|
448 |
+
A non-negative smoothing factor. If weights correspond
|
449 |
+
to the inverse of the standard-deviation of the errors in z,
|
450 |
+
then a good s-value should be found in the range
|
451 |
+
``(m-sqrt(2*m),m+sqrt(2*m))`` where m=len(x).
|
452 |
+
eps : float, optional
|
453 |
+
A threshold for determining the effective rank of an
|
454 |
+
over-determined linear system of equations (0 < eps < 1).
|
455 |
+
`eps` is not likely to need changing.
|
456 |
+
tx, ty : ndarray, optional
|
457 |
+
Rank-1 arrays of the knots of the spline for task=-1
|
458 |
+
full_output : int, optional
|
459 |
+
Non-zero to return optional outputs.
|
460 |
+
nxest, nyest : int, optional
|
461 |
+
Over-estimates of the total number of knots. If None then
|
462 |
+
``nxest = max(kx+sqrt(m/2),2*kx+3)``,
|
463 |
+
``nyest = max(ky+sqrt(m/2),2*ky+3)``.
|
464 |
+
quiet : int, optional
|
465 |
+
Non-zero to suppress printing of messages.
|
466 |
+
|
467 |
+
Returns
|
468 |
+
-------
|
469 |
+
tck : array_like
|
470 |
+
A list [tx, ty, c, kx, ky] containing the knots (tx, ty) and
|
471 |
+
coefficients (c) of the bivariate B-spline representation of the
|
472 |
+
surface along with the degree of the spline.
|
473 |
+
fp : ndarray
|
474 |
+
The weighted sum of squared residuals of the spline approximation.
|
475 |
+
ier : int
|
476 |
+
An integer flag about splrep success. Success is indicated if
|
477 |
+
ier<=0. If ier in [1,2,3] an error occurred but was not raised.
|
478 |
+
Otherwise an error is raised.
|
479 |
+
msg : str
|
480 |
+
A message corresponding to the integer flag, ier.
|
481 |
+
|
482 |
+
See Also
|
483 |
+
--------
|
484 |
+
splprep, splrep, splint, sproot, splev
|
485 |
+
UnivariateSpline, BivariateSpline
|
486 |
+
|
487 |
+
Notes
|
488 |
+
-----
|
489 |
+
See `bisplev` to evaluate the value of the B-spline given its tck
|
490 |
+
representation.
|
491 |
+
|
492 |
+
If the input data is such that input dimensions have incommensurate
|
493 |
+
units and differ by many orders of magnitude, the interpolant may have
|
494 |
+
numerical artifacts. Consider rescaling the data before interpolation.
|
495 |
+
|
496 |
+
References
|
497 |
+
----------
|
498 |
+
.. [1] Dierckx P.:An algorithm for surface fitting with spline functions
|
499 |
+
Ima J. Numer. Anal. 1 (1981) 267-283.
|
500 |
+
.. [2] Dierckx P.:An algorithm for surface fitting with spline functions
|
501 |
+
report tw50, Dept. Computer Science,K.U.Leuven, 1980.
|
502 |
+
.. [3] Dierckx P.:Curve and surface fitting with splines, Monographs on
|
503 |
+
Numerical Analysis, Oxford University Press, 1993.
|
504 |
+
|
505 |
+
Examples
|
506 |
+
--------
|
507 |
+
Examples are given :ref:`in the tutorial <tutorial-interpolate_2d_spline>`.
|
508 |
+
|
509 |
+
"""
|
510 |
+
x, y, z = map(ravel, [x, y, z]) # ensure 1-d arrays.
|
511 |
+
m = len(x)
|
512 |
+
if not (m == len(y) == len(z)):
|
513 |
+
raise TypeError('len(x)==len(y)==len(z) must hold.')
|
514 |
+
if w is None:
|
515 |
+
w = ones(m, float)
|
516 |
+
else:
|
517 |
+
w = atleast_1d(w)
|
518 |
+
if not len(w) == m:
|
519 |
+
raise TypeError('len(w)=%d is not equal to m=%d' % (len(w), m))
|
520 |
+
if xb is None:
|
521 |
+
xb = x.min()
|
522 |
+
if xe is None:
|
523 |
+
xe = x.max()
|
524 |
+
if yb is None:
|
525 |
+
yb = y.min()
|
526 |
+
if ye is None:
|
527 |
+
ye = y.max()
|
528 |
+
if not (-1 <= task <= 1):
|
529 |
+
raise TypeError('task must be -1, 0 or 1')
|
530 |
+
if s is None:
|
531 |
+
s = m - sqrt(2*m)
|
532 |
+
if tx is None and task == -1:
|
533 |
+
raise TypeError('Knots_x must be given for task=-1')
|
534 |
+
if tx is not None:
|
535 |
+
_surfit_cache['tx'] = atleast_1d(tx)
|
536 |
+
nx = len(_surfit_cache['tx'])
|
537 |
+
if ty is None and task == -1:
|
538 |
+
raise TypeError('Knots_y must be given for task=-1')
|
539 |
+
if ty is not None:
|
540 |
+
_surfit_cache['ty'] = atleast_1d(ty)
|
541 |
+
ny = len(_surfit_cache['ty'])
|
542 |
+
if task == -1 and nx < 2*kx+2:
|
543 |
+
raise TypeError('There must be at least 2*kx+2 knots_x for task=-1')
|
544 |
+
if task == -1 and ny < 2*ky+2:
|
545 |
+
raise TypeError('There must be at least 2*ky+2 knots_x for task=-1')
|
546 |
+
if not ((1 <= kx <= 5) and (1 <= ky <= 5)):
|
547 |
+
raise TypeError('Given degree of the spline (kx,ky=%d,%d) is not '
|
548 |
+
'supported. (1<=k<=5)' % (kx, ky))
|
549 |
+
if m < (kx + 1)*(ky + 1):
|
550 |
+
raise TypeError('m >= (kx+1)(ky+1) must hold')
|
551 |
+
if nxest is None:
|
552 |
+
nxest = int(kx + sqrt(m/2))
|
553 |
+
if nyest is None:
|
554 |
+
nyest = int(ky + sqrt(m/2))
|
555 |
+
nxest, nyest = max(nxest, 2*kx + 3), max(nyest, 2*ky + 3)
|
556 |
+
if task >= 0 and s == 0:
|
557 |
+
nxest = int(kx + sqrt(3*m))
|
558 |
+
nyest = int(ky + sqrt(3*m))
|
559 |
+
if task == -1:
|
560 |
+
_surfit_cache['tx'] = atleast_1d(tx)
|
561 |
+
_surfit_cache['ty'] = atleast_1d(ty)
|
562 |
+
tx, ty = _surfit_cache['tx'], _surfit_cache['ty']
|
563 |
+
wrk = _surfit_cache['wrk']
|
564 |
+
u = nxest - kx - 1
|
565 |
+
v = nyest - ky - 1
|
566 |
+
km = max(kx, ky) + 1
|
567 |
+
ne = max(nxest, nyest)
|
568 |
+
bx, by = kx*v + ky + 1, ky*u + kx + 1
|
569 |
+
b1, b2 = bx, bx + v - ky
|
570 |
+
if bx > by:
|
571 |
+
b1, b2 = by, by + u - kx
|
572 |
+
msg = "Too many data points to interpolate"
|
573 |
+
lwrk1 = _int_overflow(u*v*(2 + b1 + b2) +
|
574 |
+
2*(u + v + km*(m + ne) + ne - kx - ky) + b2 + 1,
|
575 |
+
OverflowError,
|
576 |
+
msg=msg)
|
577 |
+
lwrk2 = _int_overflow(u*v*(b2 + 1) + b2, OverflowError, msg=msg)
|
578 |
+
tx, ty, c, o = _fitpack._surfit(x, y, z, w, xb, xe, yb, ye, kx, ky,
|
579 |
+
task, s, eps, tx, ty, nxest, nyest,
|
580 |
+
wrk, lwrk1, lwrk2)
|
581 |
+
_curfit_cache['tx'] = tx
|
582 |
+
_curfit_cache['ty'] = ty
|
583 |
+
_curfit_cache['wrk'] = o['wrk']
|
584 |
+
ier, fp = o['ier'], o['fp']
|
585 |
+
tck = [tx, ty, c, kx, ky]
|
586 |
+
|
587 |
+
ierm = min(11, max(-3, ier))
|
588 |
+
if ierm <= 0 and not quiet:
|
589 |
+
_mess = (_iermess2[ierm][0] +
|
590 |
+
"\tkx,ky=%d,%d nx,ny=%d,%d m=%d fp=%f s=%f" %
|
591 |
+
(kx, ky, len(tx), len(ty), m, fp, s))
|
592 |
+
warnings.warn(RuntimeWarning(_mess), stacklevel=2)
|
593 |
+
if ierm > 0 and not full_output:
|
594 |
+
if ier in [1, 2, 3, 4, 5]:
|
595 |
+
_mess = ("\n\tkx,ky=%d,%d nx,ny=%d,%d m=%d fp=%f s=%f" %
|
596 |
+
(kx, ky, len(tx), len(ty), m, fp, s))
|
597 |
+
warnings.warn(RuntimeWarning(_iermess2[ierm][0] + _mess), stacklevel=2)
|
598 |
+
else:
|
599 |
+
try:
|
600 |
+
raise _iermess2[ierm][1](_iermess2[ierm][0])
|
601 |
+
except KeyError as e:
|
602 |
+
raise _iermess2['unknown'][1](_iermess2['unknown'][0]) from e
|
603 |
+
if full_output:
|
604 |
+
try:
|
605 |
+
return tck, fp, ier, _iermess2[ierm][0]
|
606 |
+
except KeyError:
|
607 |
+
return tck, fp, ier, _iermess2['unknown'][0]
|
608 |
+
else:
|
609 |
+
return tck
|
610 |
+
|
611 |
+
|
612 |
+
def bisplev(x, y, tck, dx=0, dy=0):
|
613 |
+
"""
|
614 |
+
Evaluate a bivariate B-spline and its derivatives.
|
615 |
+
|
616 |
+
Return a rank-2 array of spline function values (or spline derivative
|
617 |
+
values) at points given by the cross-product of the rank-1 arrays `x` and
|
618 |
+
`y`. In special cases, return an array or just a float if either `x` or
|
619 |
+
`y` or both are floats. Based on BISPEV and PARDER from FITPACK.
|
620 |
+
|
621 |
+
Parameters
|
622 |
+
----------
|
623 |
+
x, y : ndarray
|
624 |
+
Rank-1 arrays specifying the domain over which to evaluate the
|
625 |
+
spline or its derivative.
|
626 |
+
tck : tuple
|
627 |
+
A sequence of length 5 returned by `bisplrep` containing the knot
|
628 |
+
locations, the coefficients, and the degree of the spline:
|
629 |
+
[tx, ty, c, kx, ky].
|
630 |
+
dx, dy : int, optional
|
631 |
+
The orders of the partial derivatives in `x` and `y` respectively.
|
632 |
+
|
633 |
+
Returns
|
634 |
+
-------
|
635 |
+
vals : ndarray
|
636 |
+
The B-spline or its derivative evaluated over the set formed by
|
637 |
+
the cross-product of `x` and `y`.
|
638 |
+
|
639 |
+
See Also
|
640 |
+
--------
|
641 |
+
splprep, splrep, splint, sproot, splev
|
642 |
+
UnivariateSpline, BivariateSpline
|
643 |
+
|
644 |
+
Notes
|
645 |
+
-----
|
646 |
+
See `bisplrep` to generate the `tck` representation.
|
647 |
+
|
648 |
+
References
|
649 |
+
----------
|
650 |
+
.. [1] Dierckx P. : An algorithm for surface fitting
|
651 |
+
with spline functions
|
652 |
+
Ima J. Numer. Anal. 1 (1981) 267-283.
|
653 |
+
.. [2] Dierckx P. : An algorithm for surface fitting
|
654 |
+
with spline functions
|
655 |
+
report tw50, Dept. Computer Science,K.U.Leuven, 1980.
|
656 |
+
.. [3] Dierckx P. : Curve and surface fitting with splines,
|
657 |
+
Monographs on Numerical Analysis, Oxford University Press, 1993.
|
658 |
+
|
659 |
+
Examples
|
660 |
+
--------
|
661 |
+
Examples are given :ref:`in the tutorial <tutorial-interpolate_2d_spline>`.
|
662 |
+
|
663 |
+
"""
|
664 |
+
tx, ty, c, kx, ky = tck
|
665 |
+
if not (0 <= dx < kx):
|
666 |
+
raise ValueError("0 <= dx = %d < kx = %d must hold" % (dx, kx))
|
667 |
+
if not (0 <= dy < ky):
|
668 |
+
raise ValueError("0 <= dy = %d < ky = %d must hold" % (dy, ky))
|
669 |
+
x, y = map(atleast_1d, [x, y])
|
670 |
+
if (len(x.shape) != 1) or (len(y.shape) != 1):
|
671 |
+
raise ValueError("First two entries should be rank-1 arrays.")
|
672 |
+
|
673 |
+
msg = "Too many data points to interpolate."
|
674 |
+
|
675 |
+
_int_overflow(x.size * y.size, MemoryError, msg=msg)
|
676 |
+
|
677 |
+
if dx != 0 or dy != 0:
|
678 |
+
_int_overflow((tx.size - kx - 1)*(ty.size - ky - 1),
|
679 |
+
MemoryError, msg=msg)
|
680 |
+
z, ier = dfitpack.parder(tx, ty, c, kx, ky, dx, dy, x, y)
|
681 |
+
else:
|
682 |
+
z, ier = dfitpack.bispev(tx, ty, c, kx, ky, x, y)
|
683 |
+
|
684 |
+
if ier == 10:
|
685 |
+
raise ValueError("Invalid input data")
|
686 |
+
if ier:
|
687 |
+
raise TypeError("An error occurred")
|
688 |
+
z.shape = len(x), len(y)
|
689 |
+
if len(z) > 1:
|
690 |
+
return z
|
691 |
+
if len(z[0]) > 1:
|
692 |
+
return z[0]
|
693 |
+
return z[0][0]
|
694 |
+
|
695 |
+
|
696 |
+
def dblint(xa, xb, ya, yb, tck):
|
697 |
+
"""Evaluate the integral of a spline over area [xa,xb] x [ya,yb].
|
698 |
+
|
699 |
+
Parameters
|
700 |
+
----------
|
701 |
+
xa, xb : float
|
702 |
+
The end-points of the x integration interval.
|
703 |
+
ya, yb : float
|
704 |
+
The end-points of the y integration interval.
|
705 |
+
tck : list [tx, ty, c, kx, ky]
|
706 |
+
A sequence of length 5 returned by bisplrep containing the knot
|
707 |
+
locations tx, ty, the coefficients c, and the degrees kx, ky
|
708 |
+
of the spline.
|
709 |
+
|
710 |
+
Returns
|
711 |
+
-------
|
712 |
+
integ : float
|
713 |
+
The value of the resulting integral.
|
714 |
+
"""
|
715 |
+
tx, ty, c, kx, ky = tck
|
716 |
+
return dfitpack.dblint(tx, ty, c, kx, ky, xa, xb, ya, yb)
|
717 |
+
|
718 |
+
|
719 |
+
def insert(x, tck, m=1, per=0):
|
720 |
+
# see the docstring of `_fitpack_py/insert`
|
721 |
+
t, c, k = tck
|
722 |
+
try:
|
723 |
+
c[0][0]
|
724 |
+
parametric = True
|
725 |
+
except Exception:
|
726 |
+
parametric = False
|
727 |
+
if parametric:
|
728 |
+
cc = []
|
729 |
+
for c_vals in c:
|
730 |
+
tt, cc_val, kk = insert(x, [t, c_vals, k], m)
|
731 |
+
cc.append(cc_val)
|
732 |
+
return (tt, cc, kk)
|
733 |
+
else:
|
734 |
+
tt, cc, ier = _fitpack._insert(per, t, c, k, x, m)
|
735 |
+
if ier == 10:
|
736 |
+
raise ValueError("Invalid input data")
|
737 |
+
if ier:
|
738 |
+
raise TypeError("An error occurred")
|
739 |
+
return (tt, cc, k)
|
740 |
+
|
741 |
+
|
742 |
+
def splder(tck, n=1):
|
743 |
+
# see the docstring of `_fitpack_py/splder`
|
744 |
+
if n < 0:
|
745 |
+
return splantider(tck, -n)
|
746 |
+
|
747 |
+
t, c, k = tck
|
748 |
+
|
749 |
+
if n > k:
|
750 |
+
raise ValueError(f"Order of derivative (n = {n!r}) must be <= "
|
751 |
+
f"order of spline (k = {tck[2]!r})")
|
752 |
+
|
753 |
+
# Extra axes for the trailing dims of the `c` array:
|
754 |
+
sh = (slice(None),) + ((None,)*len(c.shape[1:]))
|
755 |
+
|
756 |
+
with np.errstate(invalid='raise', divide='raise'):
|
757 |
+
try:
|
758 |
+
for j in range(n):
|
759 |
+
# See e.g. Schumaker, Spline Functions: Basic Theory, Chapter 5
|
760 |
+
|
761 |
+
# Compute the denominator in the differentiation formula.
|
762 |
+
# (and append trailing dims, if necessary)
|
763 |
+
dt = t[k+1:-1] - t[1:-k-1]
|
764 |
+
dt = dt[sh]
|
765 |
+
# Compute the new coefficients
|
766 |
+
c = (c[1:-1-k] - c[:-2-k]) * k / dt
|
767 |
+
# Pad coefficient array to same size as knots (FITPACK
|
768 |
+
# convention)
|
769 |
+
c = np.r_[c, np.zeros((k,) + c.shape[1:])]
|
770 |
+
# Adjust knots
|
771 |
+
t = t[1:-1]
|
772 |
+
k -= 1
|
773 |
+
except FloatingPointError as e:
|
774 |
+
raise ValueError(("The spline has internal repeated knots "
|
775 |
+
"and is not differentiable %d times") % n) from e
|
776 |
+
|
777 |
+
return t, c, k
|
778 |
+
|
779 |
+
|
780 |
+
def splantider(tck, n=1):
|
781 |
+
# see the docstring of `_fitpack_py/splantider`
|
782 |
+
if n < 0:
|
783 |
+
return splder(tck, -n)
|
784 |
+
|
785 |
+
t, c, k = tck
|
786 |
+
|
787 |
+
# Extra axes for the trailing dims of the `c` array:
|
788 |
+
sh = (slice(None),) + (None,)*len(c.shape[1:])
|
789 |
+
|
790 |
+
for j in range(n):
|
791 |
+
# This is the inverse set of operations to splder.
|
792 |
+
|
793 |
+
# Compute the multiplier in the antiderivative formula.
|
794 |
+
dt = t[k+1:] - t[:-k-1]
|
795 |
+
dt = dt[sh]
|
796 |
+
# Compute the new coefficients
|
797 |
+
c = np.cumsum(c[:-k-1] * dt, axis=0) / (k + 1)
|
798 |
+
c = np.r_[np.zeros((1,) + c.shape[1:]),
|
799 |
+
c,
|
800 |
+
[c[-1]] * (k+2)]
|
801 |
+
# New knots
|
802 |
+
t = np.r_[t[0], t, t[-1]]
|
803 |
+
k += 1
|
804 |
+
|
805 |
+
return t, c, k
|
env-llmeval/lib/python3.10/site-packages/scipy/interpolate/_fitpack_py.py
ADDED
@@ -0,0 +1,796 @@
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
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|
1 |
+
__all__ = ['splrep', 'splprep', 'splev', 'splint', 'sproot', 'spalde',
|
2 |
+
'bisplrep', 'bisplev', 'insert', 'splder', 'splantider']
|
3 |
+
|
4 |
+
|
5 |
+
import numpy as np
|
6 |
+
|
7 |
+
# These are in the API for fitpack even if not used in fitpack.py itself.
|
8 |
+
from ._fitpack_impl import bisplrep, bisplev, dblint # noqa: F401
|
9 |
+
from . import _fitpack_impl as _impl
|
10 |
+
from ._bsplines import BSpline
|
11 |
+
|
12 |
+
|
13 |
+
def splprep(x, w=None, u=None, ub=None, ue=None, k=3, task=0, s=None, t=None,
|
14 |
+
full_output=0, nest=None, per=0, quiet=1):
|
15 |
+
"""
|
16 |
+
Find the B-spline representation of an N-D curve.
|
17 |
+
|
18 |
+
Given a list of N rank-1 arrays, `x`, which represent a curve in
|
19 |
+
N-dimensional space parametrized by `u`, find a smooth approximating
|
20 |
+
spline curve g(`u`). Uses the FORTRAN routine parcur from FITPACK.
|
21 |
+
|
22 |
+
Parameters
|
23 |
+
----------
|
24 |
+
x : array_like
|
25 |
+
A list of sample vector arrays representing the curve.
|
26 |
+
w : array_like, optional
|
27 |
+
Strictly positive rank-1 array of weights the same length as `x[0]`.
|
28 |
+
The weights are used in computing the weighted least-squares spline
|
29 |
+
fit. If the errors in the `x` values have standard-deviation given by
|
30 |
+
the vector d, then `w` should be 1/d. Default is ``ones(len(x[0]))``.
|
31 |
+
u : array_like, optional
|
32 |
+
An array of parameter values. If not given, these values are
|
33 |
+
calculated automatically as ``M = len(x[0])``, where
|
34 |
+
|
35 |
+
v[0] = 0
|
36 |
+
|
37 |
+
v[i] = v[i-1] + distance(`x[i]`, `x[i-1]`)
|
38 |
+
|
39 |
+
u[i] = v[i] / v[M-1]
|
40 |
+
|
41 |
+
ub, ue : int, optional
|
42 |
+
The end-points of the parameters interval. Defaults to
|
43 |
+
u[0] and u[-1].
|
44 |
+
k : int, optional
|
45 |
+
Degree of the spline. Cubic splines are recommended.
|
46 |
+
Even values of `k` should be avoided especially with a small s-value.
|
47 |
+
``1 <= k <= 5``, default is 3.
|
48 |
+
task : int, optional
|
49 |
+
If task==0 (default), find t and c for a given smoothing factor, s.
|
50 |
+
If task==1, find t and c for another value of the smoothing factor, s.
|
51 |
+
There must have been a previous call with task=0 or task=1
|
52 |
+
for the same set of data.
|
53 |
+
If task=-1 find the weighted least square spline for a given set of
|
54 |
+
knots, t.
|
55 |
+
s : float, optional
|
56 |
+
A smoothing condition. The amount of smoothness is determined by
|
57 |
+
satisfying the conditions: ``sum((w * (y - g))**2,axis=0) <= s``,
|
58 |
+
where g(x) is the smoothed interpolation of (x,y). The user can
|
59 |
+
use `s` to control the trade-off between closeness and smoothness
|
60 |
+
of fit. Larger `s` means more smoothing while smaller values of `s`
|
61 |
+
indicate less smoothing. Recommended values of `s` depend on the
|
62 |
+
weights, w. If the weights represent the inverse of the
|
63 |
+
standard-deviation of y, then a good `s` value should be found in
|
64 |
+
the range ``(m-sqrt(2*m),m+sqrt(2*m))``, where m is the number of
|
65 |
+
data points in x, y, and w.
|
66 |
+
t : array, optional
|
67 |
+
The knots needed for ``task=-1``.
|
68 |
+
There must be at least ``2*k+2`` knots.
|
69 |
+
full_output : int, optional
|
70 |
+
If non-zero, then return optional outputs.
|
71 |
+
nest : int, optional
|
72 |
+
An over-estimate of the total number of knots of the spline to
|
73 |
+
help in determining the storage space. By default nest=m/2.
|
74 |
+
Always large enough is nest=m+k+1.
|
75 |
+
per : int, optional
|
76 |
+
If non-zero, data points are considered periodic with period
|
77 |
+
``x[m-1] - x[0]`` and a smooth periodic spline approximation is
|
78 |
+
returned. Values of ``y[m-1]`` and ``w[m-1]`` are not used.
|
79 |
+
quiet : int, optional
|
80 |
+
Non-zero to suppress messages.
|
81 |
+
|
82 |
+
Returns
|
83 |
+
-------
|
84 |
+
tck : tuple
|
85 |
+
A tuple, ``(t,c,k)`` containing the vector of knots, the B-spline
|
86 |
+
coefficients, and the degree of the spline.
|
87 |
+
u : array
|
88 |
+
An array of the values of the parameter.
|
89 |
+
fp : float
|
90 |
+
The weighted sum of squared residuals of the spline approximation.
|
91 |
+
ier : int
|
92 |
+
An integer flag about splrep success. Success is indicated
|
93 |
+
if ier<=0. If ier in [1,2,3] an error occurred but was not raised.
|
94 |
+
Otherwise an error is raised.
|
95 |
+
msg : str
|
96 |
+
A message corresponding to the integer flag, ier.
|
97 |
+
|
98 |
+
See Also
|
99 |
+
--------
|
100 |
+
splrep, splev, sproot, spalde, splint,
|
101 |
+
bisplrep, bisplev
|
102 |
+
UnivariateSpline, BivariateSpline
|
103 |
+
BSpline
|
104 |
+
make_interp_spline
|
105 |
+
|
106 |
+
Notes
|
107 |
+
-----
|
108 |
+
See `splev` for evaluation of the spline and its derivatives.
|
109 |
+
The number of dimensions N must be smaller than 11.
|
110 |
+
|
111 |
+
The number of coefficients in the `c` array is ``k+1`` less than the number
|
112 |
+
of knots, ``len(t)``. This is in contrast with `splrep`, which zero-pads
|
113 |
+
the array of coefficients to have the same length as the array of knots.
|
114 |
+
These additional coefficients are ignored by evaluation routines, `splev`
|
115 |
+
and `BSpline`.
|
116 |
+
|
117 |
+
References
|
118 |
+
----------
|
119 |
+
.. [1] P. Dierckx, "Algorithms for smoothing data with periodic and
|
120 |
+
parametric splines, Computer Graphics and Image Processing",
|
121 |
+
20 (1982) 171-184.
|
122 |
+
.. [2] P. Dierckx, "Algorithms for smoothing data with periodic and
|
123 |
+
parametric splines", report tw55, Dept. Computer Science,
|
124 |
+
K.U.Leuven, 1981.
|
125 |
+
.. [3] P. Dierckx, "Curve and surface fitting with splines", Monographs on
|
126 |
+
Numerical Analysis, Oxford University Press, 1993.
|
127 |
+
|
128 |
+
Examples
|
129 |
+
--------
|
130 |
+
Generate a discretization of a limacon curve in the polar coordinates:
|
131 |
+
|
132 |
+
>>> import numpy as np
|
133 |
+
>>> phi = np.linspace(0, 2.*np.pi, 40)
|
134 |
+
>>> r = 0.5 + np.cos(phi) # polar coords
|
135 |
+
>>> x, y = r * np.cos(phi), r * np.sin(phi) # convert to cartesian
|
136 |
+
|
137 |
+
And interpolate:
|
138 |
+
|
139 |
+
>>> from scipy.interpolate import splprep, splev
|
140 |
+
>>> tck, u = splprep([x, y], s=0)
|
141 |
+
>>> new_points = splev(u, tck)
|
142 |
+
|
143 |
+
Notice that (i) we force interpolation by using `s=0`,
|
144 |
+
(ii) the parameterization, ``u``, is generated automatically.
|
145 |
+
Now plot the result:
|
146 |
+
|
147 |
+
>>> import matplotlib.pyplot as plt
|
148 |
+
>>> fig, ax = plt.subplots()
|
149 |
+
>>> ax.plot(x, y, 'ro')
|
150 |
+
>>> ax.plot(new_points[0], new_points[1], 'r-')
|
151 |
+
>>> plt.show()
|
152 |
+
|
153 |
+
"""
|
154 |
+
|
155 |
+
res = _impl.splprep(x, w, u, ub, ue, k, task, s, t, full_output, nest, per,
|
156 |
+
quiet)
|
157 |
+
return res
|
158 |
+
|
159 |
+
|
160 |
+
def splrep(x, y, w=None, xb=None, xe=None, k=3, task=0, s=None, t=None,
|
161 |
+
full_output=0, per=0, quiet=1):
|
162 |
+
"""
|
163 |
+
Find the B-spline representation of a 1-D curve.
|
164 |
+
|
165 |
+
Given the set of data points ``(x[i], y[i])`` determine a smooth spline
|
166 |
+
approximation of degree k on the interval ``xb <= x <= xe``.
|
167 |
+
|
168 |
+
Parameters
|
169 |
+
----------
|
170 |
+
x, y : array_like
|
171 |
+
The data points defining a curve ``y = f(x)``.
|
172 |
+
w : array_like, optional
|
173 |
+
Strictly positive rank-1 array of weights the same length as `x` and `y`.
|
174 |
+
The weights are used in computing the weighted least-squares spline
|
175 |
+
fit. If the errors in the `y` values have standard-deviation given by the
|
176 |
+
vector ``d``, then `w` should be ``1/d``. Default is ``ones(len(x))``.
|
177 |
+
xb, xe : float, optional
|
178 |
+
The interval to fit. If None, these default to ``x[0]`` and ``x[-1]``
|
179 |
+
respectively.
|
180 |
+
k : int, optional
|
181 |
+
The degree of the spline fit. It is recommended to use cubic splines.
|
182 |
+
Even values of `k` should be avoided especially with small `s` values.
|
183 |
+
``1 <= k <= 5``.
|
184 |
+
task : {1, 0, -1}, optional
|
185 |
+
If ``task==0``, find ``t`` and ``c`` for a given smoothing factor, `s`.
|
186 |
+
|
187 |
+
If ``task==1`` find ``t`` and ``c`` for another value of the smoothing factor,
|
188 |
+
`s`. There must have been a previous call with ``task=0`` or ``task=1`` for
|
189 |
+
the same set of data (``t`` will be stored an used internally)
|
190 |
+
|
191 |
+
If ``task=-1`` find the weighted least square spline for a given set of
|
192 |
+
knots, ``t``. These should be interior knots as knots on the ends will be
|
193 |
+
added automatically.
|
194 |
+
s : float, optional
|
195 |
+
A smoothing condition. The amount of smoothness is determined by
|
196 |
+
satisfying the conditions: ``sum((w * (y - g))**2,axis=0) <= s`` where ``g(x)``
|
197 |
+
is the smoothed interpolation of ``(x,y)``. The user can use `s` to control
|
198 |
+
the tradeoff between closeness and smoothness of fit. Larger `s` means
|
199 |
+
more smoothing while smaller values of `s` indicate less smoothing.
|
200 |
+
Recommended values of `s` depend on the weights, `w`. If the weights
|
201 |
+
represent the inverse of the standard-deviation of `y`, then a good `s`
|
202 |
+
value should be found in the range ``(m-sqrt(2*m),m+sqrt(2*m))`` where ``m`` is
|
203 |
+
the number of datapoints in `x`, `y`, and `w`. default : ``s=m-sqrt(2*m)`` if
|
204 |
+
weights are supplied. ``s = 0.0`` (interpolating) if no weights are
|
205 |
+
supplied.
|
206 |
+
t : array_like, optional
|
207 |
+
The knots needed for ``task=-1``. If given then task is automatically set
|
208 |
+
to ``-1``.
|
209 |
+
full_output : bool, optional
|
210 |
+
If non-zero, then return optional outputs.
|
211 |
+
per : bool, optional
|
212 |
+
If non-zero, data points are considered periodic with period ``x[m-1]`` -
|
213 |
+
``x[0]`` and a smooth periodic spline approximation is returned. Values of
|
214 |
+
``y[m-1]`` and ``w[m-1]`` are not used.
|
215 |
+
The default is zero, corresponding to boundary condition 'not-a-knot'.
|
216 |
+
quiet : bool, optional
|
217 |
+
Non-zero to suppress messages.
|
218 |
+
|
219 |
+
Returns
|
220 |
+
-------
|
221 |
+
tck : tuple
|
222 |
+
A tuple ``(t,c,k)`` containing the vector of knots, the B-spline
|
223 |
+
coefficients, and the degree of the spline.
|
224 |
+
fp : array, optional
|
225 |
+
The weighted sum of squared residuals of the spline approximation.
|
226 |
+
ier : int, optional
|
227 |
+
An integer flag about splrep success. Success is indicated if ``ier<=0``.
|
228 |
+
If ``ier in [1,2,3]``, an error occurred but was not raised. Otherwise an
|
229 |
+
error is raised.
|
230 |
+
msg : str, optional
|
231 |
+
A message corresponding to the integer flag, `ier`.
|
232 |
+
|
233 |
+
See Also
|
234 |
+
--------
|
235 |
+
UnivariateSpline, BivariateSpline
|
236 |
+
splprep, splev, sproot, spalde, splint
|
237 |
+
bisplrep, bisplev
|
238 |
+
BSpline
|
239 |
+
make_interp_spline
|
240 |
+
|
241 |
+
Notes
|
242 |
+
-----
|
243 |
+
See `splev` for evaluation of the spline and its derivatives. Uses the
|
244 |
+
FORTRAN routine ``curfit`` from FITPACK.
|
245 |
+
|
246 |
+
The user is responsible for assuring that the values of `x` are unique.
|
247 |
+
Otherwise, `splrep` will not return sensible results.
|
248 |
+
|
249 |
+
If provided, knots `t` must satisfy the Schoenberg-Whitney conditions,
|
250 |
+
i.e., there must be a subset of data points ``x[j]`` such that
|
251 |
+
``t[j] < x[j] < t[j+k+1]``, for ``j=0, 1,...,n-k-2``.
|
252 |
+
|
253 |
+
This routine zero-pads the coefficients array ``c`` to have the same length
|
254 |
+
as the array of knots ``t`` (the trailing ``k + 1`` coefficients are ignored
|
255 |
+
by the evaluation routines, `splev` and `BSpline`.) This is in contrast with
|
256 |
+
`splprep`, which does not zero-pad the coefficients.
|
257 |
+
|
258 |
+
The default boundary condition is 'not-a-knot', i.e. the first and second
|
259 |
+
segment at a curve end are the same polynomial. More boundary conditions are
|
260 |
+
available in `CubicSpline`.
|
261 |
+
|
262 |
+
References
|
263 |
+
----------
|
264 |
+
Based on algorithms described in [1]_, [2]_, [3]_, and [4]_:
|
265 |
+
|
266 |
+
.. [1] P. Dierckx, "An algorithm for smoothing, differentiation and
|
267 |
+
integration of experimental data using spline functions",
|
268 |
+
J.Comp.Appl.Maths 1 (1975) 165-184.
|
269 |
+
.. [2] P. Dierckx, "A fast algorithm for smoothing data on a rectangular
|
270 |
+
grid while using spline functions", SIAM J.Numer.Anal. 19 (1982)
|
271 |
+
1286-1304.
|
272 |
+
.. [3] P. Dierckx, "An improved algorithm for curve fitting with spline
|
273 |
+
functions", report tw54, Dept. Computer Science,K.U. Leuven, 1981.
|
274 |
+
.. [4] P. Dierckx, "Curve and surface fitting with splines", Monographs on
|
275 |
+
Numerical Analysis, Oxford University Press, 1993.
|
276 |
+
|
277 |
+
Examples
|
278 |
+
--------
|
279 |
+
You can interpolate 1-D points with a B-spline curve.
|
280 |
+
Further examples are given in
|
281 |
+
:ref:`in the tutorial <tutorial-interpolate_splXXX>`.
|
282 |
+
|
283 |
+
>>> import numpy as np
|
284 |
+
>>> import matplotlib.pyplot as plt
|
285 |
+
>>> from scipy.interpolate import splev, splrep
|
286 |
+
>>> x = np.linspace(0, 10, 10)
|
287 |
+
>>> y = np.sin(x)
|
288 |
+
>>> spl = splrep(x, y)
|
289 |
+
>>> x2 = np.linspace(0, 10, 200)
|
290 |
+
>>> y2 = splev(x2, spl)
|
291 |
+
>>> plt.plot(x, y, 'o', x2, y2)
|
292 |
+
>>> plt.show()
|
293 |
+
|
294 |
+
"""
|
295 |
+
res = _impl.splrep(x, y, w, xb, xe, k, task, s, t, full_output, per, quiet)
|
296 |
+
return res
|
297 |
+
|
298 |
+
|
299 |
+
def splev(x, tck, der=0, ext=0):
|
300 |
+
"""
|
301 |
+
Evaluate a B-spline or its derivatives.
|
302 |
+
|
303 |
+
Given the knots and coefficients of a B-spline representation, evaluate
|
304 |
+
the value of the smoothing polynomial and its derivatives. This is a
|
305 |
+
wrapper around the FORTRAN routines splev and splder of FITPACK.
|
306 |
+
|
307 |
+
Parameters
|
308 |
+
----------
|
309 |
+
x : array_like
|
310 |
+
An array of points at which to return the value of the smoothed
|
311 |
+
spline or its derivatives. If `tck` was returned from `splprep`,
|
312 |
+
then the parameter values, u should be given.
|
313 |
+
tck : 3-tuple or a BSpline object
|
314 |
+
If a tuple, then it should be a sequence of length 3 returned by
|
315 |
+
`splrep` or `splprep` containing the knots, coefficients, and degree
|
316 |
+
of the spline. (Also see Notes.)
|
317 |
+
der : int, optional
|
318 |
+
The order of derivative of the spline to compute (must be less than
|
319 |
+
or equal to k, the degree of the spline).
|
320 |
+
ext : int, optional
|
321 |
+
Controls the value returned for elements of ``x`` not in the
|
322 |
+
interval defined by the knot sequence.
|
323 |
+
|
324 |
+
* if ext=0, return the extrapolated value.
|
325 |
+
* if ext=1, return 0
|
326 |
+
* if ext=2, raise a ValueError
|
327 |
+
* if ext=3, return the boundary value.
|
328 |
+
|
329 |
+
The default value is 0.
|
330 |
+
|
331 |
+
Returns
|
332 |
+
-------
|
333 |
+
y : ndarray or list of ndarrays
|
334 |
+
An array of values representing the spline function evaluated at
|
335 |
+
the points in `x`. If `tck` was returned from `splprep`, then this
|
336 |
+
is a list of arrays representing the curve in an N-D space.
|
337 |
+
|
338 |
+
See Also
|
339 |
+
--------
|
340 |
+
splprep, splrep, sproot, spalde, splint
|
341 |
+
bisplrep, bisplev
|
342 |
+
BSpline
|
343 |
+
|
344 |
+
Notes
|
345 |
+
-----
|
346 |
+
Manipulating the tck-tuples directly is not recommended. In new code,
|
347 |
+
prefer using `BSpline` objects.
|
348 |
+
|
349 |
+
References
|
350 |
+
----------
|
351 |
+
.. [1] C. de Boor, "On calculating with b-splines", J. Approximation
|
352 |
+
Theory, 6, p.50-62, 1972.
|
353 |
+
.. [2] M. G. Cox, "The numerical evaluation of b-splines", J. Inst. Maths
|
354 |
+
Applics, 10, p.134-149, 1972.
|
355 |
+
.. [3] P. Dierckx, "Curve and surface fitting with splines", Monographs
|
356 |
+
on Numerical Analysis, Oxford University Press, 1993.
|
357 |
+
|
358 |
+
Examples
|
359 |
+
--------
|
360 |
+
Examples are given :ref:`in the tutorial <tutorial-interpolate_splXXX>`.
|
361 |
+
|
362 |
+
"""
|
363 |
+
if isinstance(tck, BSpline):
|
364 |
+
if tck.c.ndim > 1:
|
365 |
+
mesg = ("Calling splev() with BSpline objects with c.ndim > 1 is "
|
366 |
+
"not allowed. Use BSpline.__call__(x) instead.")
|
367 |
+
raise ValueError(mesg)
|
368 |
+
|
369 |
+
# remap the out-of-bounds behavior
|
370 |
+
try:
|
371 |
+
extrapolate = {0: True, }[ext]
|
372 |
+
except KeyError as e:
|
373 |
+
raise ValueError("Extrapolation mode %s is not supported "
|
374 |
+
"by BSpline." % ext) from e
|
375 |
+
|
376 |
+
return tck(x, der, extrapolate=extrapolate)
|
377 |
+
else:
|
378 |
+
return _impl.splev(x, tck, der, ext)
|
379 |
+
|
380 |
+
|
381 |
+
def splint(a, b, tck, full_output=0):
|
382 |
+
"""
|
383 |
+
Evaluate the definite integral of a B-spline between two given points.
|
384 |
+
|
385 |
+
Parameters
|
386 |
+
----------
|
387 |
+
a, b : float
|
388 |
+
The end-points of the integration interval.
|
389 |
+
tck : tuple or a BSpline instance
|
390 |
+
If a tuple, then it should be a sequence of length 3, containing the
|
391 |
+
vector of knots, the B-spline coefficients, and the degree of the
|
392 |
+
spline (see `splev`).
|
393 |
+
full_output : int, optional
|
394 |
+
Non-zero to return optional output.
|
395 |
+
|
396 |
+
Returns
|
397 |
+
-------
|
398 |
+
integral : float
|
399 |
+
The resulting integral.
|
400 |
+
wrk : ndarray
|
401 |
+
An array containing the integrals of the normalized B-splines
|
402 |
+
defined on the set of knots.
|
403 |
+
(Only returned if `full_output` is non-zero)
|
404 |
+
|
405 |
+
See Also
|
406 |
+
--------
|
407 |
+
splprep, splrep, sproot, spalde, splev
|
408 |
+
bisplrep, bisplev
|
409 |
+
BSpline
|
410 |
+
|
411 |
+
Notes
|
412 |
+
-----
|
413 |
+
`splint` silently assumes that the spline function is zero outside the data
|
414 |
+
interval (`a`, `b`).
|
415 |
+
|
416 |
+
Manipulating the tck-tuples directly is not recommended. In new code,
|
417 |
+
prefer using the `BSpline` objects.
|
418 |
+
|
419 |
+
References
|
420 |
+
----------
|
421 |
+
.. [1] P.W. Gaffney, The calculation of indefinite integrals of b-splines",
|
422 |
+
J. Inst. Maths Applics, 17, p.37-41, 1976.
|
423 |
+
.. [2] P. Dierckx, "Curve and surface fitting with splines", Monographs
|
424 |
+
on Numerical Analysis, Oxford University Press, 1993.
|
425 |
+
|
426 |
+
Examples
|
427 |
+
--------
|
428 |
+
Examples are given :ref:`in the tutorial <tutorial-interpolate_splXXX>`.
|
429 |
+
|
430 |
+
"""
|
431 |
+
if isinstance(tck, BSpline):
|
432 |
+
if tck.c.ndim > 1:
|
433 |
+
mesg = ("Calling splint() with BSpline objects with c.ndim > 1 is "
|
434 |
+
"not allowed. Use BSpline.integrate() instead.")
|
435 |
+
raise ValueError(mesg)
|
436 |
+
|
437 |
+
if full_output != 0:
|
438 |
+
mesg = ("full_output = %s is not supported. Proceeding as if "
|
439 |
+
"full_output = 0" % full_output)
|
440 |
+
|
441 |
+
return tck.integrate(a, b, extrapolate=False)
|
442 |
+
else:
|
443 |
+
return _impl.splint(a, b, tck, full_output)
|
444 |
+
|
445 |
+
|
446 |
+
def sproot(tck, mest=10):
|
447 |
+
"""
|
448 |
+
Find the roots of a cubic B-spline.
|
449 |
+
|
450 |
+
Given the knots (>=8) and coefficients of a cubic B-spline return the
|
451 |
+
roots of the spline.
|
452 |
+
|
453 |
+
Parameters
|
454 |
+
----------
|
455 |
+
tck : tuple or a BSpline object
|
456 |
+
If a tuple, then it should be a sequence of length 3, containing the
|
457 |
+
vector of knots, the B-spline coefficients, and the degree of the
|
458 |
+
spline.
|
459 |
+
The number of knots must be >= 8, and the degree must be 3.
|
460 |
+
The knots must be a montonically increasing sequence.
|
461 |
+
mest : int, optional
|
462 |
+
An estimate of the number of zeros (Default is 10).
|
463 |
+
|
464 |
+
Returns
|
465 |
+
-------
|
466 |
+
zeros : ndarray
|
467 |
+
An array giving the roots of the spline.
|
468 |
+
|
469 |
+
See Also
|
470 |
+
--------
|
471 |
+
splprep, splrep, splint, spalde, splev
|
472 |
+
bisplrep, bisplev
|
473 |
+
BSpline
|
474 |
+
|
475 |
+
Notes
|
476 |
+
-----
|
477 |
+
Manipulating the tck-tuples directly is not recommended. In new code,
|
478 |
+
prefer using the `BSpline` objects.
|
479 |
+
|
480 |
+
References
|
481 |
+
----------
|
482 |
+
.. [1] C. de Boor, "On calculating with b-splines", J. Approximation
|
483 |
+
Theory, 6, p.50-62, 1972.
|
484 |
+
.. [2] M. G. Cox, "The numerical evaluation of b-splines", J. Inst. Maths
|
485 |
+
Applics, 10, p.134-149, 1972.
|
486 |
+
.. [3] P. Dierckx, "Curve and surface fitting with splines", Monographs
|
487 |
+
on Numerical Analysis, Oxford University Press, 1993.
|
488 |
+
|
489 |
+
Examples
|
490 |
+
--------
|
491 |
+
|
492 |
+
For some data, this method may miss a root. This happens when one of
|
493 |
+
the spline knots (which FITPACK places automatically) happens to
|
494 |
+
coincide with the true root. A workaround is to convert to `PPoly`,
|
495 |
+
which uses a different root-finding algorithm.
|
496 |
+
|
497 |
+
For example,
|
498 |
+
|
499 |
+
>>> x = [1.96, 1.97, 1.98, 1.99, 2.00, 2.01, 2.02, 2.03, 2.04, 2.05]
|
500 |
+
>>> y = [-6.365470e-03, -4.790580e-03, -3.204320e-03, -1.607270e-03,
|
501 |
+
... 4.440892e-16, 1.616930e-03, 3.243000e-03, 4.877670e-03,
|
502 |
+
... 6.520430e-03, 8.170770e-03]
|
503 |
+
>>> from scipy.interpolate import splrep, sproot, PPoly
|
504 |
+
>>> tck = splrep(x, y, s=0)
|
505 |
+
>>> sproot(tck)
|
506 |
+
array([], dtype=float64)
|
507 |
+
|
508 |
+
Converting to a PPoly object does find the roots at `x=2`:
|
509 |
+
|
510 |
+
>>> ppoly = PPoly.from_spline(tck)
|
511 |
+
>>> ppoly.roots(extrapolate=False)
|
512 |
+
array([2.])
|
513 |
+
|
514 |
+
|
515 |
+
Further examples are given :ref:`in the tutorial
|
516 |
+
<tutorial-interpolate_splXXX>`.
|
517 |
+
|
518 |
+
"""
|
519 |
+
if isinstance(tck, BSpline):
|
520 |
+
if tck.c.ndim > 1:
|
521 |
+
mesg = ("Calling sproot() with BSpline objects with c.ndim > 1 is "
|
522 |
+
"not allowed.")
|
523 |
+
raise ValueError(mesg)
|
524 |
+
|
525 |
+
t, c, k = tck.tck
|
526 |
+
|
527 |
+
# _impl.sproot expects the interpolation axis to be last, so roll it.
|
528 |
+
# NB: This transpose is a no-op if c is 1D.
|
529 |
+
sh = tuple(range(c.ndim))
|
530 |
+
c = c.transpose(sh[1:] + (0,))
|
531 |
+
return _impl.sproot((t, c, k), mest)
|
532 |
+
else:
|
533 |
+
return _impl.sproot(tck, mest)
|
534 |
+
|
535 |
+
|
536 |
+
def spalde(x, tck):
|
537 |
+
"""
|
538 |
+
Evaluate all derivatives of a B-spline.
|
539 |
+
|
540 |
+
Given the knots and coefficients of a cubic B-spline compute all
|
541 |
+
derivatives up to order k at a point (or set of points).
|
542 |
+
|
543 |
+
Parameters
|
544 |
+
----------
|
545 |
+
x : array_like
|
546 |
+
A point or a set of points at which to evaluate the derivatives.
|
547 |
+
Note that ``t(k) <= x <= t(n-k+1)`` must hold for each `x`.
|
548 |
+
tck : tuple
|
549 |
+
A tuple (t,c,k) containing the vector of knots,
|
550 |
+
the B-spline coefficients, and the degree of the spline.
|
551 |
+
|
552 |
+
Returns
|
553 |
+
-------
|
554 |
+
results : {ndarray, list of ndarrays}
|
555 |
+
An array (or a list of arrays) containing all derivatives
|
556 |
+
up to order k inclusive for each point `x`.
|
557 |
+
|
558 |
+
See Also
|
559 |
+
--------
|
560 |
+
splprep, splrep, splint, sproot, splev, bisplrep, bisplev,
|
561 |
+
UnivariateSpline, BivariateSpline
|
562 |
+
|
563 |
+
References
|
564 |
+
----------
|
565 |
+
.. [1] de Boor C : On calculating with b-splines, J. Approximation Theory
|
566 |
+
6 (1972) 50-62.
|
567 |
+
.. [2] Cox M.G. : The numerical evaluation of b-splines, J. Inst. Maths
|
568 |
+
applics 10 (1972) 134-149.
|
569 |
+
.. [3] Dierckx P. : Curve and surface fitting with splines, Monographs on
|
570 |
+
Numerical Analysis, Oxford University Press, 1993.
|
571 |
+
|
572 |
+
"""
|
573 |
+
if isinstance(tck, BSpline):
|
574 |
+
raise TypeError("spalde does not accept BSpline instances.")
|
575 |
+
else:
|
576 |
+
return _impl.spalde(x, tck)
|
577 |
+
|
578 |
+
|
579 |
+
def insert(x, tck, m=1, per=0):
|
580 |
+
"""
|
581 |
+
Insert knots into a B-spline.
|
582 |
+
|
583 |
+
Given the knots and coefficients of a B-spline representation, create a
|
584 |
+
new B-spline with a knot inserted `m` times at point `x`.
|
585 |
+
This is a wrapper around the FORTRAN routine insert of FITPACK.
|
586 |
+
|
587 |
+
Parameters
|
588 |
+
----------
|
589 |
+
x (u) : float
|
590 |
+
A knot value at which to insert a new knot. If `tck` was returned
|
591 |
+
from ``splprep``, then the parameter values, u should be given.
|
592 |
+
tck : a `BSpline` instance or a tuple
|
593 |
+
If tuple, then it is expected to be a tuple (t,c,k) containing
|
594 |
+
the vector of knots, the B-spline coefficients, and the degree of
|
595 |
+
the spline.
|
596 |
+
m : int, optional
|
597 |
+
The number of times to insert the given knot (its multiplicity).
|
598 |
+
Default is 1.
|
599 |
+
per : int, optional
|
600 |
+
If non-zero, the input spline is considered periodic.
|
601 |
+
|
602 |
+
Returns
|
603 |
+
-------
|
604 |
+
BSpline instance or a tuple
|
605 |
+
A new B-spline with knots t, coefficients c, and degree k.
|
606 |
+
``t(k+1) <= x <= t(n-k)``, where k is the degree of the spline.
|
607 |
+
In case of a periodic spline (``per != 0``) there must be
|
608 |
+
either at least k interior knots t(j) satisfying ``t(k+1)<t(j)<=x``
|
609 |
+
or at least k interior knots t(j) satisfying ``x<=t(j)<t(n-k)``.
|
610 |
+
A tuple is returned iff the input argument `tck` is a tuple, otherwise
|
611 |
+
a BSpline object is constructed and returned.
|
612 |
+
|
613 |
+
Notes
|
614 |
+
-----
|
615 |
+
Based on algorithms from [1]_ and [2]_.
|
616 |
+
|
617 |
+
Manipulating the tck-tuples directly is not recommended. In new code,
|
618 |
+
prefer using the `BSpline` objects, in particular `BSpline.insert_knot`
|
619 |
+
method.
|
620 |
+
|
621 |
+
See Also
|
622 |
+
--------
|
623 |
+
BSpline.insert_knot
|
624 |
+
|
625 |
+
References
|
626 |
+
----------
|
627 |
+
.. [1] W. Boehm, "Inserting new knots into b-spline curves.",
|
628 |
+
Computer Aided Design, 12, p.199-201, 1980.
|
629 |
+
.. [2] P. Dierckx, "Curve and surface fitting with splines, Monographs on
|
630 |
+
Numerical Analysis", Oxford University Press, 1993.
|
631 |
+
|
632 |
+
Examples
|
633 |
+
--------
|
634 |
+
You can insert knots into a B-spline.
|
635 |
+
|
636 |
+
>>> from scipy.interpolate import splrep, insert
|
637 |
+
>>> import numpy as np
|
638 |
+
>>> x = np.linspace(0, 10, 5)
|
639 |
+
>>> y = np.sin(x)
|
640 |
+
>>> tck = splrep(x, y)
|
641 |
+
>>> tck[0]
|
642 |
+
array([ 0., 0., 0., 0., 5., 10., 10., 10., 10.])
|
643 |
+
|
644 |
+
A knot is inserted:
|
645 |
+
|
646 |
+
>>> tck_inserted = insert(3, tck)
|
647 |
+
>>> tck_inserted[0]
|
648 |
+
array([ 0., 0., 0., 0., 3., 5., 10., 10., 10., 10.])
|
649 |
+
|
650 |
+
Some knots are inserted:
|
651 |
+
|
652 |
+
>>> tck_inserted2 = insert(8, tck, m=3)
|
653 |
+
>>> tck_inserted2[0]
|
654 |
+
array([ 0., 0., 0., 0., 5., 8., 8., 8., 10., 10., 10., 10.])
|
655 |
+
|
656 |
+
"""
|
657 |
+
if isinstance(tck, BSpline):
|
658 |
+
|
659 |
+
t, c, k = tck.tck
|
660 |
+
|
661 |
+
# FITPACK expects the interpolation axis to be last, so roll it over
|
662 |
+
# NB: if c array is 1D, transposes are no-ops
|
663 |
+
sh = tuple(range(c.ndim))
|
664 |
+
c = c.transpose(sh[1:] + (0,))
|
665 |
+
t_, c_, k_ = _impl.insert(x, (t, c, k), m, per)
|
666 |
+
|
667 |
+
# and roll the last axis back
|
668 |
+
c_ = np.asarray(c_)
|
669 |
+
c_ = c_.transpose((sh[-1],) + sh[:-1])
|
670 |
+
return BSpline(t_, c_, k_)
|
671 |
+
else:
|
672 |
+
return _impl.insert(x, tck, m, per)
|
673 |
+
|
674 |
+
|
675 |
+
def splder(tck, n=1):
|
676 |
+
"""
|
677 |
+
Compute the spline representation of the derivative of a given spline
|
678 |
+
|
679 |
+
Parameters
|
680 |
+
----------
|
681 |
+
tck : BSpline instance or a tuple of (t, c, k)
|
682 |
+
Spline whose derivative to compute
|
683 |
+
n : int, optional
|
684 |
+
Order of derivative to evaluate. Default: 1
|
685 |
+
|
686 |
+
Returns
|
687 |
+
-------
|
688 |
+
`BSpline` instance or tuple
|
689 |
+
Spline of order k2=k-n representing the derivative
|
690 |
+
of the input spline.
|
691 |
+
A tuple is returned iff the input argument `tck` is a tuple, otherwise
|
692 |
+
a BSpline object is constructed and returned.
|
693 |
+
|
694 |
+
See Also
|
695 |
+
--------
|
696 |
+
splantider, splev, spalde
|
697 |
+
BSpline
|
698 |
+
|
699 |
+
Notes
|
700 |
+
-----
|
701 |
+
|
702 |
+
.. versionadded:: 0.13.0
|
703 |
+
|
704 |
+
Examples
|
705 |
+
--------
|
706 |
+
This can be used for finding maxima of a curve:
|
707 |
+
|
708 |
+
>>> from scipy.interpolate import splrep, splder, sproot
|
709 |
+
>>> import numpy as np
|
710 |
+
>>> x = np.linspace(0, 10, 70)
|
711 |
+
>>> y = np.sin(x)
|
712 |
+
>>> spl = splrep(x, y, k=4)
|
713 |
+
|
714 |
+
Now, differentiate the spline and find the zeros of the
|
715 |
+
derivative. (NB: `sproot` only works for order 3 splines, so we
|
716 |
+
fit an order 4 spline):
|
717 |
+
|
718 |
+
>>> dspl = splder(spl)
|
719 |
+
>>> sproot(dspl) / np.pi
|
720 |
+
array([ 0.50000001, 1.5 , 2.49999998])
|
721 |
+
|
722 |
+
This agrees well with roots :math:`\\pi/2 + n\\pi` of
|
723 |
+
:math:`\\cos(x) = \\sin'(x)`.
|
724 |
+
|
725 |
+
"""
|
726 |
+
if isinstance(tck, BSpline):
|
727 |
+
return tck.derivative(n)
|
728 |
+
else:
|
729 |
+
return _impl.splder(tck, n)
|
730 |
+
|
731 |
+
|
732 |
+
def splantider(tck, n=1):
|
733 |
+
"""
|
734 |
+
Compute the spline for the antiderivative (integral) of a given spline.
|
735 |
+
|
736 |
+
Parameters
|
737 |
+
----------
|
738 |
+
tck : BSpline instance or a tuple of (t, c, k)
|
739 |
+
Spline whose antiderivative to compute
|
740 |
+
n : int, optional
|
741 |
+
Order of antiderivative to evaluate. Default: 1
|
742 |
+
|
743 |
+
Returns
|
744 |
+
-------
|
745 |
+
BSpline instance or a tuple of (t2, c2, k2)
|
746 |
+
Spline of order k2=k+n representing the antiderivative of the input
|
747 |
+
spline.
|
748 |
+
A tuple is returned iff the input argument `tck` is a tuple, otherwise
|
749 |
+
a BSpline object is constructed and returned.
|
750 |
+
|
751 |
+
See Also
|
752 |
+
--------
|
753 |
+
splder, splev, spalde
|
754 |
+
BSpline
|
755 |
+
|
756 |
+
Notes
|
757 |
+
-----
|
758 |
+
The `splder` function is the inverse operation of this function.
|
759 |
+
Namely, ``splder(splantider(tck))`` is identical to `tck`, modulo
|
760 |
+
rounding error.
|
761 |
+
|
762 |
+
.. versionadded:: 0.13.0
|
763 |
+
|
764 |
+
Examples
|
765 |
+
--------
|
766 |
+
>>> from scipy.interpolate import splrep, splder, splantider, splev
|
767 |
+
>>> import numpy as np
|
768 |
+
>>> x = np.linspace(0, np.pi/2, 70)
|
769 |
+
>>> y = 1 / np.sqrt(1 - 0.8*np.sin(x)**2)
|
770 |
+
>>> spl = splrep(x, y)
|
771 |
+
|
772 |
+
The derivative is the inverse operation of the antiderivative,
|
773 |
+
although some floating point error accumulates:
|
774 |
+
|
775 |
+
>>> splev(1.7, spl), splev(1.7, splder(splantider(spl)))
|
776 |
+
(array(2.1565429877197317), array(2.1565429877201865))
|
777 |
+
|
778 |
+
Antiderivative can be used to evaluate definite integrals:
|
779 |
+
|
780 |
+
>>> ispl = splantider(spl)
|
781 |
+
>>> splev(np.pi/2, ispl) - splev(0, ispl)
|
782 |
+
2.2572053588768486
|
783 |
+
|
784 |
+
This is indeed an approximation to the complete elliptic integral
|
785 |
+
:math:`K(m) = \\int_0^{\\pi/2} [1 - m\\sin^2 x]^{-1/2} dx`:
|
786 |
+
|
787 |
+
>>> from scipy.special import ellipk
|
788 |
+
>>> ellipk(0.8)
|
789 |
+
2.2572053268208538
|
790 |
+
|
791 |
+
"""
|
792 |
+
if isinstance(tck, BSpline):
|
793 |
+
return tck.antiderivative(n)
|
794 |
+
else:
|
795 |
+
return _impl.splantider(tck, n)
|
796 |
+
|
env-llmeval/lib/python3.10/site-packages/scipy/interpolate/_ndbspline.py
ADDED
@@ -0,0 +1,358 @@
|
|
|
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|
|
|
|
|
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|
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|
|
|
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|
|
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|
|
|
|
|
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|
|
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|
|
|
|
|
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|
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|
|
|
|
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|
|
|
|
|
|
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|
|
|
|
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|
|
|
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|
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|
|
|
|
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|
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|
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|
|
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|
|
|
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|
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|
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|
|
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|
|
|
|
|
|
|
|
|
|
|
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|
|
|
|
|
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|
|
|
|
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|
|
|
|
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|
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|
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|
|
|
|
|
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|
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|
|
|
|
|
|
|
|
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|
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|
|
|
|
|
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|
|
|
|
|
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|
|
|
|
|
|
|
|
|
|
|
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|
|
|
|
|
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|
|
|
|
|
|
|
|
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|
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|
|
|
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|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
1 |
+
import itertools
|
2 |
+
import functools
|
3 |
+
import operator
|
4 |
+
import numpy as np
|
5 |
+
|
6 |
+
from math import prod
|
7 |
+
|
8 |
+
from . import _bspl # type: ignore
|
9 |
+
|
10 |
+
import scipy.sparse.linalg as ssl
|
11 |
+
from scipy.sparse import csr_array
|
12 |
+
|
13 |
+
from ._bsplines import _not_a_knot
|
14 |
+
|
15 |
+
__all__ = ["NdBSpline"]
|
16 |
+
|
17 |
+
|
18 |
+
def _get_dtype(dtype):
|
19 |
+
"""Return np.complex128 for complex dtypes, np.float64 otherwise."""
|
20 |
+
if np.issubdtype(dtype, np.complexfloating):
|
21 |
+
return np.complex128
|
22 |
+
else:
|
23 |
+
return np.float64
|
24 |
+
|
25 |
+
|
26 |
+
class NdBSpline:
|
27 |
+
"""Tensor product spline object.
|
28 |
+
|
29 |
+
The value at point ``xp = (x1, x2, ..., xN)`` is evaluated as a linear
|
30 |
+
combination of products of one-dimensional b-splines in each of the ``N``
|
31 |
+
dimensions::
|
32 |
+
|
33 |
+
c[i1, i2, ..., iN] * B(x1; i1, t1) * B(x2; i2, t2) * ... * B(xN; iN, tN)
|
34 |
+
|
35 |
+
|
36 |
+
Here ``B(x; i, t)`` is the ``i``-th b-spline defined by the knot vector
|
37 |
+
``t`` evaluated at ``x``.
|
38 |
+
|
39 |
+
Parameters
|
40 |
+
----------
|
41 |
+
t : tuple of 1D ndarrays
|
42 |
+
knot vectors in directions 1, 2, ... N,
|
43 |
+
``len(t[i]) == n[i] + k + 1``
|
44 |
+
c : ndarray, shape (n1, n2, ..., nN, ...)
|
45 |
+
b-spline coefficients
|
46 |
+
k : int or length-d tuple of integers
|
47 |
+
spline degrees.
|
48 |
+
A single integer is interpreted as having this degree for
|
49 |
+
all dimensions.
|
50 |
+
extrapolate : bool, optional
|
51 |
+
Whether to extrapolate out-of-bounds inputs, or return `nan`.
|
52 |
+
Default is to extrapolate.
|
53 |
+
|
54 |
+
Attributes
|
55 |
+
----------
|
56 |
+
t : tuple of ndarrays
|
57 |
+
Knots vectors.
|
58 |
+
c : ndarray
|
59 |
+
Coefficients of the tensor-produce spline.
|
60 |
+
k : tuple of integers
|
61 |
+
Degrees for each dimension.
|
62 |
+
extrapolate : bool, optional
|
63 |
+
Whether to extrapolate or return nans for out-of-bounds inputs.
|
64 |
+
Defaults to true.
|
65 |
+
|
66 |
+
Methods
|
67 |
+
-------
|
68 |
+
__call__
|
69 |
+
design_matrix
|
70 |
+
|
71 |
+
See Also
|
72 |
+
--------
|
73 |
+
BSpline : a one-dimensional B-spline object
|
74 |
+
NdPPoly : an N-dimensional piecewise tensor product polynomial
|
75 |
+
|
76 |
+
"""
|
77 |
+
def __init__(self, t, c, k, *, extrapolate=None):
|
78 |
+
ndim = len(t)
|
79 |
+
|
80 |
+
try:
|
81 |
+
len(k)
|
82 |
+
except TypeError:
|
83 |
+
# make k a tuple
|
84 |
+
k = (k,)*ndim
|
85 |
+
|
86 |
+
if len(k) != ndim:
|
87 |
+
raise ValueError(f"{len(t) = } != {len(k) = }.")
|
88 |
+
|
89 |
+
self.k = tuple(operator.index(ki) for ki in k)
|
90 |
+
self.t = tuple(np.ascontiguousarray(ti, dtype=float) for ti in t)
|
91 |
+
self.c = np.asarray(c)
|
92 |
+
|
93 |
+
if extrapolate is None:
|
94 |
+
extrapolate = True
|
95 |
+
self.extrapolate = bool(extrapolate)
|
96 |
+
|
97 |
+
self.c = np.asarray(c)
|
98 |
+
|
99 |
+
for d in range(ndim):
|
100 |
+
td = self.t[d]
|
101 |
+
kd = self.k[d]
|
102 |
+
n = td.shape[0] - kd - 1
|
103 |
+
if kd < 0:
|
104 |
+
raise ValueError(f"Spline degree in dimension {d} cannot be"
|
105 |
+
f" negative.")
|
106 |
+
if td.ndim != 1:
|
107 |
+
raise ValueError(f"Knot vector in dimension {d} must be"
|
108 |
+
f" one-dimensional.")
|
109 |
+
if n < kd + 1:
|
110 |
+
raise ValueError(f"Need at least {2*kd + 2} knots for degree"
|
111 |
+
f" {kd} in dimension {d}.")
|
112 |
+
if (np.diff(td) < 0).any():
|
113 |
+
raise ValueError(f"Knots in dimension {d} must be in a"
|
114 |
+
f" non-decreasing order.")
|
115 |
+
if len(np.unique(td[kd:n + 1])) < 2:
|
116 |
+
raise ValueError(f"Need at least two internal knots in"
|
117 |
+
f" dimension {d}.")
|
118 |
+
if not np.isfinite(td).all():
|
119 |
+
raise ValueError(f"Knots in dimension {d} should not have"
|
120 |
+
f" nans or infs.")
|
121 |
+
if self.c.ndim < ndim:
|
122 |
+
raise ValueError(f"Coefficients must be at least"
|
123 |
+
f" {d}-dimensional.")
|
124 |
+
if self.c.shape[d] != n:
|
125 |
+
raise ValueError(f"Knots, coefficients and degree in dimension"
|
126 |
+
f" {d} are inconsistent:"
|
127 |
+
f" got {self.c.shape[d]} coefficients for"
|
128 |
+
f" {len(td)} knots, need at least {n} for"
|
129 |
+
f" k={k}.")
|
130 |
+
|
131 |
+
dt = _get_dtype(self.c.dtype)
|
132 |
+
self.c = np.ascontiguousarray(self.c, dtype=dt)
|
133 |
+
|
134 |
+
def __call__(self, xi, *, nu=None, extrapolate=None):
|
135 |
+
"""Evaluate the tensor product b-spline at ``xi``.
|
136 |
+
|
137 |
+
Parameters
|
138 |
+
----------
|
139 |
+
xi : array_like, shape(..., ndim)
|
140 |
+
The coordinates to evaluate the interpolator at.
|
141 |
+
This can be a list or tuple of ndim-dimensional points
|
142 |
+
or an array with the shape (num_points, ndim).
|
143 |
+
nu : array_like, optional, shape (ndim,)
|
144 |
+
Orders of derivatives to evaluate. Each must be non-negative.
|
145 |
+
Defaults to the zeroth derivivative.
|
146 |
+
extrapolate : bool, optional
|
147 |
+
Whether to exrapolate based on first and last intervals in each
|
148 |
+
dimension, or return `nan`. Default is to ``self.extrapolate``.
|
149 |
+
|
150 |
+
Returns
|
151 |
+
-------
|
152 |
+
values : ndarray, shape ``xi.shape[:-1] + self.c.shape[ndim:]``
|
153 |
+
Interpolated values at ``xi``
|
154 |
+
"""
|
155 |
+
ndim = len(self.t)
|
156 |
+
|
157 |
+
if extrapolate is None:
|
158 |
+
extrapolate = self.extrapolate
|
159 |
+
extrapolate = bool(extrapolate)
|
160 |
+
|
161 |
+
if nu is None:
|
162 |
+
nu = np.zeros((ndim,), dtype=np.intc)
|
163 |
+
else:
|
164 |
+
nu = np.asarray(nu, dtype=np.intc)
|
165 |
+
if nu.ndim != 1 or nu.shape[0] != ndim:
|
166 |
+
raise ValueError(
|
167 |
+
f"invalid number of derivative orders {nu = } for "
|
168 |
+
f"ndim = {len(self.t)}.")
|
169 |
+
if any(nu < 0):
|
170 |
+
raise ValueError(f"derivatives must be positive, got {nu = }")
|
171 |
+
|
172 |
+
# prepare xi : shape (..., m1, ..., md) -> (1, m1, ..., md)
|
173 |
+
xi = np.asarray(xi, dtype=float)
|
174 |
+
xi_shape = xi.shape
|
175 |
+
xi = xi.reshape(-1, xi_shape[-1])
|
176 |
+
xi = np.ascontiguousarray(xi)
|
177 |
+
|
178 |
+
if xi_shape[-1] != ndim:
|
179 |
+
raise ValueError(f"Shapes: xi.shape={xi_shape} and ndim={ndim}")
|
180 |
+
|
181 |
+
# prepare k & t
|
182 |
+
_k = np.asarray(self.k, dtype=np.dtype("long"))
|
183 |
+
|
184 |
+
# pack the knots into a single array
|
185 |
+
len_t = [len(ti) for ti in self.t]
|
186 |
+
_t = np.empty((ndim, max(len_t)), dtype=float)
|
187 |
+
_t.fill(np.nan)
|
188 |
+
for d in range(ndim):
|
189 |
+
_t[d, :len(self.t[d])] = self.t[d]
|
190 |
+
len_t = np.asarray(len_t, dtype=np.dtype("long"))
|
191 |
+
|
192 |
+
# tabulate the flat indices for iterating over the (k+1)**ndim subarray
|
193 |
+
shape = tuple(kd + 1 for kd in self.k)
|
194 |
+
indices = np.unravel_index(np.arange(prod(shape)), shape)
|
195 |
+
_indices_k1d = np.asarray(indices, dtype=np.intp).T
|
196 |
+
|
197 |
+
# prepare the coefficients: flatten the trailing dimensions
|
198 |
+
c1 = self.c.reshape(self.c.shape[:ndim] + (-1,))
|
199 |
+
c1r = c1.ravel()
|
200 |
+
|
201 |
+
# replacement for np.ravel_multi_index for indexing of `c1`:
|
202 |
+
_strides_c1 = np.asarray([s // c1.dtype.itemsize
|
203 |
+
for s in c1.strides], dtype=np.intp)
|
204 |
+
|
205 |
+
num_c_tr = c1.shape[-1] # # of trailing coefficients
|
206 |
+
out = np.empty(xi.shape[:-1] + (num_c_tr,), dtype=c1.dtype)
|
207 |
+
|
208 |
+
_bspl.evaluate_ndbspline(xi,
|
209 |
+
_t,
|
210 |
+
len_t,
|
211 |
+
_k,
|
212 |
+
nu,
|
213 |
+
extrapolate,
|
214 |
+
c1r,
|
215 |
+
num_c_tr,
|
216 |
+
_strides_c1,
|
217 |
+
_indices_k1d,
|
218 |
+
out,)
|
219 |
+
|
220 |
+
return out.reshape(xi_shape[:-1] + self.c.shape[ndim:])
|
221 |
+
|
222 |
+
@classmethod
|
223 |
+
def design_matrix(cls, xvals, t, k, extrapolate=True):
|
224 |
+
"""Construct the design matrix as a CSR format sparse array.
|
225 |
+
|
226 |
+
Parameters
|
227 |
+
----------
|
228 |
+
xvals : ndarray, shape(npts, ndim)
|
229 |
+
Data points. ``xvals[j, :]`` gives the ``j``-th data point as an
|
230 |
+
``ndim``-dimensional array.
|
231 |
+
t : tuple of 1D ndarrays, length-ndim
|
232 |
+
Knot vectors in directions 1, 2, ... ndim,
|
233 |
+
k : int
|
234 |
+
B-spline degree.
|
235 |
+
extrapolate : bool, optional
|
236 |
+
Whether to extrapolate out-of-bounds values of raise a `ValueError`
|
237 |
+
|
238 |
+
Returns
|
239 |
+
-------
|
240 |
+
design_matrix : a CSR array
|
241 |
+
Each row of the design matrix corresponds to a value in `xvals` and
|
242 |
+
contains values of b-spline basis elements which are non-zero
|
243 |
+
at this value.
|
244 |
+
|
245 |
+
"""
|
246 |
+
xvals = np.asarray(xvals, dtype=float)
|
247 |
+
ndim = xvals.shape[-1]
|
248 |
+
if len(t) != ndim:
|
249 |
+
raise ValueError(
|
250 |
+
f"Data and knots are inconsistent: len(t) = {len(t)} for "
|
251 |
+
f" {ndim = }."
|
252 |
+
)
|
253 |
+
try:
|
254 |
+
len(k)
|
255 |
+
except TypeError:
|
256 |
+
# make k a tuple
|
257 |
+
k = (k,)*ndim
|
258 |
+
|
259 |
+
kk = np.asarray(k, dtype=np.int32)
|
260 |
+
data, indices, indptr = _bspl._colloc_nd(xvals, t, kk)
|
261 |
+
return csr_array((data, indices, indptr))
|
262 |
+
|
263 |
+
|
264 |
+
def _iter_solve(a, b, solver=ssl.gcrotmk, **solver_args):
|
265 |
+
# work around iterative solvers not accepting multiple r.h.s.
|
266 |
+
|
267 |
+
# also work around a.dtype == float64 and b.dtype == complex128
|
268 |
+
# cf https://github.com/scipy/scipy/issues/19644
|
269 |
+
if np.issubdtype(b.dtype, np.complexfloating):
|
270 |
+
real = _iter_solve(a, b.real, solver, **solver_args)
|
271 |
+
imag = _iter_solve(a, b.imag, solver, **solver_args)
|
272 |
+
return real + 1j*imag
|
273 |
+
|
274 |
+
if b.ndim == 2 and b.shape[1] !=1:
|
275 |
+
res = np.empty_like(b)
|
276 |
+
for j in range(b.shape[1]):
|
277 |
+
res[:, j], info = solver(a, b[:, j], **solver_args)
|
278 |
+
if info != 0:
|
279 |
+
raise ValueError(f"{solver = } returns {info =} for column {j}.")
|
280 |
+
return res
|
281 |
+
else:
|
282 |
+
res, info = solver(a, b, **solver_args)
|
283 |
+
if info != 0:
|
284 |
+
raise ValueError(f"{solver = } returns {info = }.")
|
285 |
+
return res
|
286 |
+
|
287 |
+
|
288 |
+
def make_ndbspl(points, values, k=3, *, solver=ssl.gcrotmk, **solver_args):
|
289 |
+
"""Construct an interpolating NdBspline.
|
290 |
+
|
291 |
+
Parameters
|
292 |
+
----------
|
293 |
+
points : tuple of ndarrays of float, with shapes (m1,), ... (mN,)
|
294 |
+
The points defining the regular grid in N dimensions. The points in
|
295 |
+
each dimension (i.e. every element of the `points` tuple) must be
|
296 |
+
strictly ascending or descending.
|
297 |
+
values : ndarray of float, shape (m1, ..., mN, ...)
|
298 |
+
The data on the regular grid in n dimensions.
|
299 |
+
k : int, optional
|
300 |
+
The spline degree. Must be odd. Default is cubic, k=3
|
301 |
+
solver : a `scipy.sparse.linalg` solver (iterative or direct), optional.
|
302 |
+
An iterative solver from `scipy.sparse.linalg` or a direct one,
|
303 |
+
`sparse.sparse.linalg.spsolve`.
|
304 |
+
Used to solve the sparse linear system
|
305 |
+
``design_matrix @ coefficients = rhs`` for the coefficients.
|
306 |
+
Default is `scipy.sparse.linalg.gcrotmk`
|
307 |
+
solver_args : dict, optional
|
308 |
+
Additional arguments for the solver. The call signature is
|
309 |
+
``solver(csr_array, rhs_vector, **solver_args)``
|
310 |
+
|
311 |
+
Returns
|
312 |
+
-------
|
313 |
+
spl : NdBSpline object
|
314 |
+
|
315 |
+
Notes
|
316 |
+
-----
|
317 |
+
Boundary conditions are not-a-knot in all dimensions.
|
318 |
+
"""
|
319 |
+
ndim = len(points)
|
320 |
+
xi_shape = tuple(len(x) for x in points)
|
321 |
+
|
322 |
+
try:
|
323 |
+
len(k)
|
324 |
+
except TypeError:
|
325 |
+
# make k a tuple
|
326 |
+
k = (k,)*ndim
|
327 |
+
|
328 |
+
for d, point in enumerate(points):
|
329 |
+
numpts = len(np.atleast_1d(point))
|
330 |
+
if numpts <= k[d]:
|
331 |
+
raise ValueError(f"There are {numpts} points in dimension {d},"
|
332 |
+
f" but order {k[d]} requires at least "
|
333 |
+
f" {k[d]+1} points per dimension.")
|
334 |
+
|
335 |
+
t = tuple(_not_a_knot(np.asarray(points[d], dtype=float), k[d])
|
336 |
+
for d in range(ndim))
|
337 |
+
xvals = np.asarray([xv for xv in itertools.product(*points)], dtype=float)
|
338 |
+
|
339 |
+
# construct the colocation matrix
|
340 |
+
matr = NdBSpline.design_matrix(xvals, t, k)
|
341 |
+
|
342 |
+
# Solve for the coefficients given `values`.
|
343 |
+
# Trailing dimensions: first ndim dimensions are data, the rest are batch
|
344 |
+
# dimensions, so stack `values` into a 2D array for `spsolve` to undestand.
|
345 |
+
v_shape = values.shape
|
346 |
+
vals_shape = (prod(v_shape[:ndim]), prod(v_shape[ndim:]))
|
347 |
+
vals = values.reshape(vals_shape)
|
348 |
+
|
349 |
+
if solver != ssl.spsolve:
|
350 |
+
solver = functools.partial(_iter_solve, solver=solver)
|
351 |
+
if "atol" not in solver_args:
|
352 |
+
# avoid a DeprecationWarning, grumble grumble
|
353 |
+
solver_args["atol"] = 1e-6
|
354 |
+
|
355 |
+
coef = solver(matr, vals, **solver_args)
|
356 |
+
coef = coef.reshape(xi_shape + v_shape[ndim:])
|
357 |
+
return NdBSpline(t, coef, k)
|
358 |
+
|
env-llmeval/lib/python3.10/site-packages/scipy/interpolate/_ndgriddata.py
ADDED
@@ -0,0 +1,332 @@
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|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
1 |
+
"""
|
2 |
+
Convenience interface to N-D interpolation
|
3 |
+
|
4 |
+
.. versionadded:: 0.9
|
5 |
+
|
6 |
+
"""
|
7 |
+
import numpy as np
|
8 |
+
from .interpnd import LinearNDInterpolator, NDInterpolatorBase, \
|
9 |
+
CloughTocher2DInterpolator, _ndim_coords_from_arrays
|
10 |
+
from scipy.spatial import cKDTree
|
11 |
+
|
12 |
+
__all__ = ['griddata', 'NearestNDInterpolator', 'LinearNDInterpolator',
|
13 |
+
'CloughTocher2DInterpolator']
|
14 |
+
|
15 |
+
#------------------------------------------------------------------------------
|
16 |
+
# Nearest-neighbor interpolation
|
17 |
+
#------------------------------------------------------------------------------
|
18 |
+
|
19 |
+
|
20 |
+
class NearestNDInterpolator(NDInterpolatorBase):
|
21 |
+
"""NearestNDInterpolator(x, y).
|
22 |
+
|
23 |
+
Nearest-neighbor interpolator in N > 1 dimensions.
|
24 |
+
|
25 |
+
.. versionadded:: 0.9
|
26 |
+
|
27 |
+
Methods
|
28 |
+
-------
|
29 |
+
__call__
|
30 |
+
|
31 |
+
Parameters
|
32 |
+
----------
|
33 |
+
x : (npoints, ndims) 2-D ndarray of floats
|
34 |
+
Data point coordinates.
|
35 |
+
y : (npoints, ) 1-D ndarray of float or complex
|
36 |
+
Data values.
|
37 |
+
rescale : boolean, optional
|
38 |
+
Rescale points to unit cube before performing interpolation.
|
39 |
+
This is useful if some of the input dimensions have
|
40 |
+
incommensurable units and differ by many orders of magnitude.
|
41 |
+
|
42 |
+
.. versionadded:: 0.14.0
|
43 |
+
tree_options : dict, optional
|
44 |
+
Options passed to the underlying ``cKDTree``.
|
45 |
+
|
46 |
+
.. versionadded:: 0.17.0
|
47 |
+
|
48 |
+
See Also
|
49 |
+
--------
|
50 |
+
griddata :
|
51 |
+
Interpolate unstructured D-D data.
|
52 |
+
LinearNDInterpolator :
|
53 |
+
Piecewise linear interpolator in N dimensions.
|
54 |
+
CloughTocher2DInterpolator :
|
55 |
+
Piecewise cubic, C1 smooth, curvature-minimizing interpolator in 2D.
|
56 |
+
interpn : Interpolation on a regular grid or rectilinear grid.
|
57 |
+
RegularGridInterpolator : Interpolator on a regular or rectilinear grid
|
58 |
+
in arbitrary dimensions (`interpn` wraps this
|
59 |
+
class).
|
60 |
+
|
61 |
+
Notes
|
62 |
+
-----
|
63 |
+
Uses ``scipy.spatial.cKDTree``
|
64 |
+
|
65 |
+
.. note:: For data on a regular grid use `interpn` instead.
|
66 |
+
|
67 |
+
Examples
|
68 |
+
--------
|
69 |
+
We can interpolate values on a 2D plane:
|
70 |
+
|
71 |
+
>>> from scipy.interpolate import NearestNDInterpolator
|
72 |
+
>>> import numpy as np
|
73 |
+
>>> import matplotlib.pyplot as plt
|
74 |
+
>>> rng = np.random.default_rng()
|
75 |
+
>>> x = rng.random(10) - 0.5
|
76 |
+
>>> y = rng.random(10) - 0.5
|
77 |
+
>>> z = np.hypot(x, y)
|
78 |
+
>>> X = np.linspace(min(x), max(x))
|
79 |
+
>>> Y = np.linspace(min(y), max(y))
|
80 |
+
>>> X, Y = np.meshgrid(X, Y) # 2D grid for interpolation
|
81 |
+
>>> interp = NearestNDInterpolator(list(zip(x, y)), z)
|
82 |
+
>>> Z = interp(X, Y)
|
83 |
+
>>> plt.pcolormesh(X, Y, Z, shading='auto')
|
84 |
+
>>> plt.plot(x, y, "ok", label="input point")
|
85 |
+
>>> plt.legend()
|
86 |
+
>>> plt.colorbar()
|
87 |
+
>>> plt.axis("equal")
|
88 |
+
>>> plt.show()
|
89 |
+
|
90 |
+
"""
|
91 |
+
|
92 |
+
def __init__(self, x, y, rescale=False, tree_options=None):
|
93 |
+
NDInterpolatorBase.__init__(self, x, y, rescale=rescale,
|
94 |
+
need_contiguous=False,
|
95 |
+
need_values=False)
|
96 |
+
if tree_options is None:
|
97 |
+
tree_options = dict()
|
98 |
+
self.tree = cKDTree(self.points, **tree_options)
|
99 |
+
self.values = np.asarray(y)
|
100 |
+
|
101 |
+
def __call__(self, *args, **query_options):
|
102 |
+
"""
|
103 |
+
Evaluate interpolator at given points.
|
104 |
+
|
105 |
+
Parameters
|
106 |
+
----------
|
107 |
+
x1, x2, ... xn : array-like of float
|
108 |
+
Points where to interpolate data at.
|
109 |
+
x1, x2, ... xn can be array-like of float with broadcastable shape.
|
110 |
+
or x1 can be array-like of float with shape ``(..., ndim)``
|
111 |
+
**query_options
|
112 |
+
This allows ``eps``, ``p``, ``distance_upper_bound``, and ``workers``
|
113 |
+
being passed to the cKDTree's query function to be explicitly set.
|
114 |
+
See `scipy.spatial.cKDTree.query` for an overview of the different options.
|
115 |
+
|
116 |
+
.. versionadded:: 1.12.0
|
117 |
+
|
118 |
+
"""
|
119 |
+
# For the sake of enabling subclassing, NDInterpolatorBase._set_xi performs
|
120 |
+
# some operations which are not required by NearestNDInterpolator.__call__,
|
121 |
+
# hence here we operate on xi directly, without calling a parent class function.
|
122 |
+
xi = _ndim_coords_from_arrays(args, ndim=self.points.shape[1])
|
123 |
+
xi = self._check_call_shape(xi)
|
124 |
+
xi = self._scale_x(xi)
|
125 |
+
|
126 |
+
# We need to handle two important cases:
|
127 |
+
# (1) the case where xi has trailing dimensions (..., ndim), and
|
128 |
+
# (2) the case where y has trailing dimensions
|
129 |
+
# We will first flatten xi to deal with case (1),
|
130 |
+
# do the computation in flattened array while retaining y's dimensionality,
|
131 |
+
# and then reshape the interpolated values back to match xi's shape.
|
132 |
+
|
133 |
+
# Flatten xi for the query
|
134 |
+
xi_flat = xi.reshape(-1, xi.shape[-1])
|
135 |
+
original_shape = xi.shape
|
136 |
+
flattened_shape = xi_flat.shape
|
137 |
+
|
138 |
+
# if distance_upper_bound is set to not be infinite,
|
139 |
+
# then we need to consider the case where cKDtree
|
140 |
+
# does not find any points within distance_upper_bound to return.
|
141 |
+
# It marks those points as having infinte distance, which is what will be used
|
142 |
+
# below to mask the array and return only the points that were deemed
|
143 |
+
# to have a close enough neighbor to return something useful.
|
144 |
+
dist, i = self.tree.query(xi_flat, **query_options)
|
145 |
+
valid_mask = np.isfinite(dist)
|
146 |
+
|
147 |
+
# create a holder interp_values array and fill with nans.
|
148 |
+
if self.values.ndim > 1:
|
149 |
+
interp_shape = flattened_shape[:-1] + self.values.shape[1:]
|
150 |
+
else:
|
151 |
+
interp_shape = flattened_shape[:-1]
|
152 |
+
|
153 |
+
if np.issubdtype(self.values.dtype, np.complexfloating):
|
154 |
+
interp_values = np.full(interp_shape, np.nan, dtype=self.values.dtype)
|
155 |
+
else:
|
156 |
+
interp_values = np.full(interp_shape, np.nan)
|
157 |
+
|
158 |
+
interp_values[valid_mask] = self.values[i[valid_mask], ...]
|
159 |
+
|
160 |
+
if self.values.ndim > 1:
|
161 |
+
new_shape = original_shape[:-1] + self.values.shape[1:]
|
162 |
+
else:
|
163 |
+
new_shape = original_shape[:-1]
|
164 |
+
interp_values = interp_values.reshape(new_shape)
|
165 |
+
|
166 |
+
return interp_values
|
167 |
+
|
168 |
+
|
169 |
+
#------------------------------------------------------------------------------
|
170 |
+
# Convenience interface function
|
171 |
+
#------------------------------------------------------------------------------
|
172 |
+
|
173 |
+
|
174 |
+
def griddata(points, values, xi, method='linear', fill_value=np.nan,
|
175 |
+
rescale=False):
|
176 |
+
"""
|
177 |
+
Interpolate unstructured D-D data.
|
178 |
+
|
179 |
+
Parameters
|
180 |
+
----------
|
181 |
+
points : 2-D ndarray of floats with shape (n, D), or length D tuple of 1-D ndarrays with shape (n,).
|
182 |
+
Data point coordinates.
|
183 |
+
values : ndarray of float or complex, shape (n,)
|
184 |
+
Data values.
|
185 |
+
xi : 2-D ndarray of floats with shape (m, D), or length D tuple of ndarrays broadcastable to the same shape.
|
186 |
+
Points at which to interpolate data.
|
187 |
+
method : {'linear', 'nearest', 'cubic'}, optional
|
188 |
+
Method of interpolation. One of
|
189 |
+
|
190 |
+
``nearest``
|
191 |
+
return the value at the data point closest to
|
192 |
+
the point of interpolation. See `NearestNDInterpolator` for
|
193 |
+
more details.
|
194 |
+
|
195 |
+
``linear``
|
196 |
+
tessellate the input point set to N-D
|
197 |
+
simplices, and interpolate linearly on each simplex. See
|
198 |
+
`LinearNDInterpolator` for more details.
|
199 |
+
|
200 |
+
``cubic`` (1-D)
|
201 |
+
return the value determined from a cubic
|
202 |
+
spline.
|
203 |
+
|
204 |
+
``cubic`` (2-D)
|
205 |
+
return the value determined from a
|
206 |
+
piecewise cubic, continuously differentiable (C1), and
|
207 |
+
approximately curvature-minimizing polynomial surface. See
|
208 |
+
`CloughTocher2DInterpolator` for more details.
|
209 |
+
fill_value : float, optional
|
210 |
+
Value used to fill in for requested points outside of the
|
211 |
+
convex hull of the input points. If not provided, then the
|
212 |
+
default is ``nan``. This option has no effect for the
|
213 |
+
'nearest' method.
|
214 |
+
rescale : bool, optional
|
215 |
+
Rescale points to unit cube before performing interpolation.
|
216 |
+
This is useful if some of the input dimensions have
|
217 |
+
incommensurable units and differ by many orders of magnitude.
|
218 |
+
|
219 |
+
.. versionadded:: 0.14.0
|
220 |
+
|
221 |
+
Returns
|
222 |
+
-------
|
223 |
+
ndarray
|
224 |
+
Array of interpolated values.
|
225 |
+
|
226 |
+
See Also
|
227 |
+
--------
|
228 |
+
LinearNDInterpolator :
|
229 |
+
Piecewise linear interpolator in N dimensions.
|
230 |
+
NearestNDInterpolator :
|
231 |
+
Nearest-neighbor interpolator in N dimensions.
|
232 |
+
CloughTocher2DInterpolator :
|
233 |
+
Piecewise cubic, C1 smooth, curvature-minimizing interpolator in 2D.
|
234 |
+
interpn : Interpolation on a regular grid or rectilinear grid.
|
235 |
+
RegularGridInterpolator : Interpolator on a regular or rectilinear grid
|
236 |
+
in arbitrary dimensions (`interpn` wraps this
|
237 |
+
class).
|
238 |
+
|
239 |
+
Notes
|
240 |
+
-----
|
241 |
+
|
242 |
+
.. versionadded:: 0.9
|
243 |
+
|
244 |
+
.. note:: For data on a regular grid use `interpn` instead.
|
245 |
+
|
246 |
+
Examples
|
247 |
+
--------
|
248 |
+
|
249 |
+
Suppose we want to interpolate the 2-D function
|
250 |
+
|
251 |
+
>>> import numpy as np
|
252 |
+
>>> def func(x, y):
|
253 |
+
... return x*(1-x)*np.cos(4*np.pi*x) * np.sin(4*np.pi*y**2)**2
|
254 |
+
|
255 |
+
on a grid in [0, 1]x[0, 1]
|
256 |
+
|
257 |
+
>>> grid_x, grid_y = np.mgrid[0:1:100j, 0:1:200j]
|
258 |
+
|
259 |
+
but we only know its values at 1000 data points:
|
260 |
+
|
261 |
+
>>> rng = np.random.default_rng()
|
262 |
+
>>> points = rng.random((1000, 2))
|
263 |
+
>>> values = func(points[:,0], points[:,1])
|
264 |
+
|
265 |
+
This can be done with `griddata` -- below we try out all of the
|
266 |
+
interpolation methods:
|
267 |
+
|
268 |
+
>>> from scipy.interpolate import griddata
|
269 |
+
>>> grid_z0 = griddata(points, values, (grid_x, grid_y), method='nearest')
|
270 |
+
>>> grid_z1 = griddata(points, values, (grid_x, grid_y), method='linear')
|
271 |
+
>>> grid_z2 = griddata(points, values, (grid_x, grid_y), method='cubic')
|
272 |
+
|
273 |
+
One can see that the exact result is reproduced by all of the
|
274 |
+
methods to some degree, but for this smooth function the piecewise
|
275 |
+
cubic interpolant gives the best results:
|
276 |
+
|
277 |
+
>>> import matplotlib.pyplot as plt
|
278 |
+
>>> plt.subplot(221)
|
279 |
+
>>> plt.imshow(func(grid_x, grid_y).T, extent=(0,1,0,1), origin='lower')
|
280 |
+
>>> plt.plot(points[:,0], points[:,1], 'k.', ms=1)
|
281 |
+
>>> plt.title('Original')
|
282 |
+
>>> plt.subplot(222)
|
283 |
+
>>> plt.imshow(grid_z0.T, extent=(0,1,0,1), origin='lower')
|
284 |
+
>>> plt.title('Nearest')
|
285 |
+
>>> plt.subplot(223)
|
286 |
+
>>> plt.imshow(grid_z1.T, extent=(0,1,0,1), origin='lower')
|
287 |
+
>>> plt.title('Linear')
|
288 |
+
>>> plt.subplot(224)
|
289 |
+
>>> plt.imshow(grid_z2.T, extent=(0,1,0,1), origin='lower')
|
290 |
+
>>> plt.title('Cubic')
|
291 |
+
>>> plt.gcf().set_size_inches(6, 6)
|
292 |
+
>>> plt.show()
|
293 |
+
|
294 |
+
""" # numpy/numpydoc#87 # noqa: E501
|
295 |
+
|
296 |
+
points = _ndim_coords_from_arrays(points)
|
297 |
+
|
298 |
+
if points.ndim < 2:
|
299 |
+
ndim = points.ndim
|
300 |
+
else:
|
301 |
+
ndim = points.shape[-1]
|
302 |
+
|
303 |
+
if ndim == 1 and method in ('nearest', 'linear', 'cubic'):
|
304 |
+
from ._interpolate import interp1d
|
305 |
+
points = points.ravel()
|
306 |
+
if isinstance(xi, tuple):
|
307 |
+
if len(xi) != 1:
|
308 |
+
raise ValueError("invalid number of dimensions in xi")
|
309 |
+
xi, = xi
|
310 |
+
# Sort points/values together, necessary as input for interp1d
|
311 |
+
idx = np.argsort(points)
|
312 |
+
points = points[idx]
|
313 |
+
values = values[idx]
|
314 |
+
if method == 'nearest':
|
315 |
+
fill_value = 'extrapolate'
|
316 |
+
ip = interp1d(points, values, kind=method, axis=0, bounds_error=False,
|
317 |
+
fill_value=fill_value)
|
318 |
+
return ip(xi)
|
319 |
+
elif method == 'nearest':
|
320 |
+
ip = NearestNDInterpolator(points, values, rescale=rescale)
|
321 |
+
return ip(xi)
|
322 |
+
elif method == 'linear':
|
323 |
+
ip = LinearNDInterpolator(points, values, fill_value=fill_value,
|
324 |
+
rescale=rescale)
|
325 |
+
return ip(xi)
|
326 |
+
elif method == 'cubic' and ndim == 2:
|
327 |
+
ip = CloughTocher2DInterpolator(points, values, fill_value=fill_value,
|
328 |
+
rescale=rescale)
|
329 |
+
return ip(xi)
|
330 |
+
else:
|
331 |
+
raise ValueError("Unknown interpolation method %r for "
|
332 |
+
"%d dimensional data" % (method, ndim))
|
env-llmeval/lib/python3.10/site-packages/scipy/interpolate/_polyint.py
ADDED
@@ -0,0 +1,938 @@
|
|
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|
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|
1 |
+
import warnings
|
2 |
+
|
3 |
+
import numpy as np
|
4 |
+
from scipy.special import factorial
|
5 |
+
from scipy._lib._util import _asarray_validated, float_factorial, check_random_state
|
6 |
+
|
7 |
+
|
8 |
+
__all__ = ["KroghInterpolator", "krogh_interpolate",
|
9 |
+
"BarycentricInterpolator", "barycentric_interpolate",
|
10 |
+
"approximate_taylor_polynomial"]
|
11 |
+
|
12 |
+
|
13 |
+
def _isscalar(x):
|
14 |
+
"""Check whether x is if a scalar type, or 0-dim"""
|
15 |
+
return np.isscalar(x) or hasattr(x, 'shape') and x.shape == ()
|
16 |
+
|
17 |
+
|
18 |
+
class _Interpolator1D:
|
19 |
+
"""
|
20 |
+
Common features in univariate interpolation
|
21 |
+
|
22 |
+
Deal with input data type and interpolation axis rolling. The
|
23 |
+
actual interpolator can assume the y-data is of shape (n, r) where
|
24 |
+
`n` is the number of x-points, and `r` the number of variables,
|
25 |
+
and use self.dtype as the y-data type.
|
26 |
+
|
27 |
+
Attributes
|
28 |
+
----------
|
29 |
+
_y_axis
|
30 |
+
Axis along which the interpolation goes in the original array
|
31 |
+
_y_extra_shape
|
32 |
+
Additional trailing shape of the input arrays, excluding
|
33 |
+
the interpolation axis.
|
34 |
+
dtype
|
35 |
+
Dtype of the y-data arrays. Can be set via _set_dtype, which
|
36 |
+
forces it to be float or complex.
|
37 |
+
|
38 |
+
Methods
|
39 |
+
-------
|
40 |
+
__call__
|
41 |
+
_prepare_x
|
42 |
+
_finish_y
|
43 |
+
_reshape_yi
|
44 |
+
_set_yi
|
45 |
+
_set_dtype
|
46 |
+
_evaluate
|
47 |
+
|
48 |
+
"""
|
49 |
+
|
50 |
+
__slots__ = ('_y_axis', '_y_extra_shape', 'dtype')
|
51 |
+
|
52 |
+
def __init__(self, xi=None, yi=None, axis=None):
|
53 |
+
self._y_axis = axis
|
54 |
+
self._y_extra_shape = None
|
55 |
+
self.dtype = None
|
56 |
+
if yi is not None:
|
57 |
+
self._set_yi(yi, xi=xi, axis=axis)
|
58 |
+
|
59 |
+
def __call__(self, x):
|
60 |
+
"""
|
61 |
+
Evaluate the interpolant
|
62 |
+
|
63 |
+
Parameters
|
64 |
+
----------
|
65 |
+
x : array_like
|
66 |
+
Point or points at which to evaluate the interpolant.
|
67 |
+
|
68 |
+
Returns
|
69 |
+
-------
|
70 |
+
y : array_like
|
71 |
+
Interpolated values. Shape is determined by replacing
|
72 |
+
the interpolation axis in the original array with the shape of `x`.
|
73 |
+
|
74 |
+
Notes
|
75 |
+
-----
|
76 |
+
Input values `x` must be convertible to `float` values like `int`
|
77 |
+
or `float`.
|
78 |
+
|
79 |
+
"""
|
80 |
+
x, x_shape = self._prepare_x(x)
|
81 |
+
y = self._evaluate(x)
|
82 |
+
return self._finish_y(y, x_shape)
|
83 |
+
|
84 |
+
def _evaluate(self, x):
|
85 |
+
"""
|
86 |
+
Actually evaluate the value of the interpolator.
|
87 |
+
"""
|
88 |
+
raise NotImplementedError()
|
89 |
+
|
90 |
+
def _prepare_x(self, x):
|
91 |
+
"""Reshape input x array to 1-D"""
|
92 |
+
x = _asarray_validated(x, check_finite=False, as_inexact=True)
|
93 |
+
x_shape = x.shape
|
94 |
+
return x.ravel(), x_shape
|
95 |
+
|
96 |
+
def _finish_y(self, y, x_shape):
|
97 |
+
"""Reshape interpolated y back to an N-D array similar to initial y"""
|
98 |
+
y = y.reshape(x_shape + self._y_extra_shape)
|
99 |
+
if self._y_axis != 0 and x_shape != ():
|
100 |
+
nx = len(x_shape)
|
101 |
+
ny = len(self._y_extra_shape)
|
102 |
+
s = (list(range(nx, nx + self._y_axis))
|
103 |
+
+ list(range(nx)) + list(range(nx+self._y_axis, nx+ny)))
|
104 |
+
y = y.transpose(s)
|
105 |
+
return y
|
106 |
+
|
107 |
+
def _reshape_yi(self, yi, check=False):
|
108 |
+
yi = np.moveaxis(np.asarray(yi), self._y_axis, 0)
|
109 |
+
if check and yi.shape[1:] != self._y_extra_shape:
|
110 |
+
ok_shape = "{!r} + (N,) + {!r}".format(self._y_extra_shape[-self._y_axis:],
|
111 |
+
self._y_extra_shape[:-self._y_axis])
|
112 |
+
raise ValueError("Data must be of shape %s" % ok_shape)
|
113 |
+
return yi.reshape((yi.shape[0], -1))
|
114 |
+
|
115 |
+
def _set_yi(self, yi, xi=None, axis=None):
|
116 |
+
if axis is None:
|
117 |
+
axis = self._y_axis
|
118 |
+
if axis is None:
|
119 |
+
raise ValueError("no interpolation axis specified")
|
120 |
+
|
121 |
+
yi = np.asarray(yi)
|
122 |
+
|
123 |
+
shape = yi.shape
|
124 |
+
if shape == ():
|
125 |
+
shape = (1,)
|
126 |
+
if xi is not None and shape[axis] != len(xi):
|
127 |
+
raise ValueError("x and y arrays must be equal in length along "
|
128 |
+
"interpolation axis.")
|
129 |
+
|
130 |
+
self._y_axis = (axis % yi.ndim)
|
131 |
+
self._y_extra_shape = yi.shape[:self._y_axis] + yi.shape[self._y_axis+1:]
|
132 |
+
self.dtype = None
|
133 |
+
self._set_dtype(yi.dtype)
|
134 |
+
|
135 |
+
def _set_dtype(self, dtype, union=False):
|
136 |
+
if np.issubdtype(dtype, np.complexfloating) \
|
137 |
+
or np.issubdtype(self.dtype, np.complexfloating):
|
138 |
+
self.dtype = np.complex128
|
139 |
+
else:
|
140 |
+
if not union or self.dtype != np.complex128:
|
141 |
+
self.dtype = np.float64
|
142 |
+
|
143 |
+
|
144 |
+
class _Interpolator1DWithDerivatives(_Interpolator1D):
|
145 |
+
def derivatives(self, x, der=None):
|
146 |
+
"""
|
147 |
+
Evaluate several derivatives of the polynomial at the point `x`
|
148 |
+
|
149 |
+
Produce an array of derivatives evaluated at the point `x`.
|
150 |
+
|
151 |
+
Parameters
|
152 |
+
----------
|
153 |
+
x : array_like
|
154 |
+
Point or points at which to evaluate the derivatives
|
155 |
+
der : int or list or None, optional
|
156 |
+
How many derivatives to evaluate, or None for all potentially
|
157 |
+
nonzero derivatives (that is, a number equal to the number
|
158 |
+
of points), or a list of derivatives to evaluate. This number
|
159 |
+
includes the function value as the '0th' derivative.
|
160 |
+
|
161 |
+
Returns
|
162 |
+
-------
|
163 |
+
d : ndarray
|
164 |
+
Array with derivatives; ``d[j]`` contains the jth derivative.
|
165 |
+
Shape of ``d[j]`` is determined by replacing the interpolation
|
166 |
+
axis in the original array with the shape of `x`.
|
167 |
+
|
168 |
+
Examples
|
169 |
+
--------
|
170 |
+
>>> from scipy.interpolate import KroghInterpolator
|
171 |
+
>>> KroghInterpolator([0,0,0],[1,2,3]).derivatives(0)
|
172 |
+
array([1.0,2.0,3.0])
|
173 |
+
>>> KroghInterpolator([0,0,0],[1,2,3]).derivatives([0,0])
|
174 |
+
array([[1.0,1.0],
|
175 |
+
[2.0,2.0],
|
176 |
+
[3.0,3.0]])
|
177 |
+
|
178 |
+
"""
|
179 |
+
x, x_shape = self._prepare_x(x)
|
180 |
+
y = self._evaluate_derivatives(x, der)
|
181 |
+
|
182 |
+
y = y.reshape((y.shape[0],) + x_shape + self._y_extra_shape)
|
183 |
+
if self._y_axis != 0 and x_shape != ():
|
184 |
+
nx = len(x_shape)
|
185 |
+
ny = len(self._y_extra_shape)
|
186 |
+
s = ([0] + list(range(nx+1, nx + self._y_axis+1))
|
187 |
+
+ list(range(1, nx+1)) +
|
188 |
+
list(range(nx+1+self._y_axis, nx+ny+1)))
|
189 |
+
y = y.transpose(s)
|
190 |
+
return y
|
191 |
+
|
192 |
+
def derivative(self, x, der=1):
|
193 |
+
"""
|
194 |
+
Evaluate a single derivative of the polynomial at the point `x`.
|
195 |
+
|
196 |
+
Parameters
|
197 |
+
----------
|
198 |
+
x : array_like
|
199 |
+
Point or points at which to evaluate the derivatives
|
200 |
+
|
201 |
+
der : integer, optional
|
202 |
+
Which derivative to evaluate (default: first derivative).
|
203 |
+
This number includes the function value as 0th derivative.
|
204 |
+
|
205 |
+
Returns
|
206 |
+
-------
|
207 |
+
d : ndarray
|
208 |
+
Derivative interpolated at the x-points. Shape of `d` is
|
209 |
+
determined by replacing the interpolation axis in the
|
210 |
+
original array with the shape of `x`.
|
211 |
+
|
212 |
+
Notes
|
213 |
+
-----
|
214 |
+
This may be computed by evaluating all derivatives up to the desired
|
215 |
+
one (using self.derivatives()) and then discarding the rest.
|
216 |
+
|
217 |
+
"""
|
218 |
+
x, x_shape = self._prepare_x(x)
|
219 |
+
y = self._evaluate_derivatives(x, der+1)
|
220 |
+
return self._finish_y(y[der], x_shape)
|
221 |
+
|
222 |
+
def _evaluate_derivatives(self, x, der=None):
|
223 |
+
"""
|
224 |
+
Actually evaluate the derivatives.
|
225 |
+
|
226 |
+
Parameters
|
227 |
+
----------
|
228 |
+
x : array_like
|
229 |
+
1D array of points at which to evaluate the derivatives
|
230 |
+
der : integer, optional
|
231 |
+
The number of derivatives to evaluate, from 'order 0' (der=1)
|
232 |
+
to order der-1. If omitted, return all possibly-non-zero
|
233 |
+
derivatives, ie 0 to order n-1.
|
234 |
+
|
235 |
+
Returns
|
236 |
+
-------
|
237 |
+
d : ndarray
|
238 |
+
Array of shape ``(der, x.size, self.yi.shape[1])`` containing
|
239 |
+
the derivatives from 0 to der-1
|
240 |
+
"""
|
241 |
+
raise NotImplementedError()
|
242 |
+
|
243 |
+
|
244 |
+
class KroghInterpolator(_Interpolator1DWithDerivatives):
|
245 |
+
"""
|
246 |
+
Interpolating polynomial for a set of points.
|
247 |
+
|
248 |
+
The polynomial passes through all the pairs ``(xi, yi)``. One may
|
249 |
+
additionally specify a number of derivatives at each point `xi`;
|
250 |
+
this is done by repeating the value `xi` and specifying the
|
251 |
+
derivatives as successive `yi` values.
|
252 |
+
|
253 |
+
Allows evaluation of the polynomial and all its derivatives.
|
254 |
+
For reasons of numerical stability, this function does not compute
|
255 |
+
the coefficients of the polynomial, although they can be obtained
|
256 |
+
by evaluating all the derivatives.
|
257 |
+
|
258 |
+
Parameters
|
259 |
+
----------
|
260 |
+
xi : array_like, shape (npoints, )
|
261 |
+
Known x-coordinates. Must be sorted in increasing order.
|
262 |
+
yi : array_like, shape (..., npoints, ...)
|
263 |
+
Known y-coordinates. When an xi occurs two or more times in
|
264 |
+
a row, the corresponding yi's represent derivative values. The length of `yi`
|
265 |
+
along the interpolation axis must be equal to the length of `xi`. Use the
|
266 |
+
`axis` parameter to select the correct axis.
|
267 |
+
axis : int, optional
|
268 |
+
Axis in the `yi` array corresponding to the x-coordinate values. Defaults to
|
269 |
+
``axis=0``.
|
270 |
+
|
271 |
+
Notes
|
272 |
+
-----
|
273 |
+
Be aware that the algorithms implemented here are not necessarily
|
274 |
+
the most numerically stable known. Moreover, even in a world of
|
275 |
+
exact computation, unless the x coordinates are chosen very
|
276 |
+
carefully - Chebyshev zeros (e.g., cos(i*pi/n)) are a good choice -
|
277 |
+
polynomial interpolation itself is a very ill-conditioned process
|
278 |
+
due to the Runge phenomenon. In general, even with well-chosen
|
279 |
+
x values, degrees higher than about thirty cause problems with
|
280 |
+
numerical instability in this code.
|
281 |
+
|
282 |
+
Based on [1]_.
|
283 |
+
|
284 |
+
References
|
285 |
+
----------
|
286 |
+
.. [1] Krogh, "Efficient Algorithms for Polynomial Interpolation
|
287 |
+
and Numerical Differentiation", 1970.
|
288 |
+
|
289 |
+
Examples
|
290 |
+
--------
|
291 |
+
To produce a polynomial that is zero at 0 and 1 and has
|
292 |
+
derivative 2 at 0, call
|
293 |
+
|
294 |
+
>>> from scipy.interpolate import KroghInterpolator
|
295 |
+
>>> KroghInterpolator([0,0,1],[0,2,0])
|
296 |
+
|
297 |
+
This constructs the quadratic :math:`2x^2-2x`. The derivative condition
|
298 |
+
is indicated by the repeated zero in the `xi` array; the corresponding
|
299 |
+
yi values are 0, the function value, and 2, the derivative value.
|
300 |
+
|
301 |
+
For another example, given `xi`, `yi`, and a derivative `ypi` for each
|
302 |
+
point, appropriate arrays can be constructed as:
|
303 |
+
|
304 |
+
>>> import numpy as np
|
305 |
+
>>> rng = np.random.default_rng()
|
306 |
+
>>> xi = np.linspace(0, 1, 5)
|
307 |
+
>>> yi, ypi = rng.random((2, 5))
|
308 |
+
>>> xi_k, yi_k = np.repeat(xi, 2), np.ravel(np.dstack((yi,ypi)))
|
309 |
+
>>> KroghInterpolator(xi_k, yi_k)
|
310 |
+
|
311 |
+
To produce a vector-valued polynomial, supply a higher-dimensional
|
312 |
+
array for `yi`:
|
313 |
+
|
314 |
+
>>> KroghInterpolator([0,1],[[2,3],[4,5]])
|
315 |
+
|
316 |
+
This constructs a linear polynomial giving (2,3) at 0 and (4,5) at 1.
|
317 |
+
|
318 |
+
"""
|
319 |
+
|
320 |
+
def __init__(self, xi, yi, axis=0):
|
321 |
+
super().__init__(xi, yi, axis)
|
322 |
+
|
323 |
+
self.xi = np.asarray(xi)
|
324 |
+
self.yi = self._reshape_yi(yi)
|
325 |
+
self.n, self.r = self.yi.shape
|
326 |
+
|
327 |
+
if (deg := self.xi.size) > 30:
|
328 |
+
warnings.warn(f"{deg} degrees provided, degrees higher than about"
|
329 |
+
" thirty cause problems with numerical instability "
|
330 |
+
"with 'KroghInterpolator'", stacklevel=2)
|
331 |
+
|
332 |
+
c = np.zeros((self.n+1, self.r), dtype=self.dtype)
|
333 |
+
c[0] = self.yi[0]
|
334 |
+
Vk = np.zeros((self.n, self.r), dtype=self.dtype)
|
335 |
+
for k in range(1, self.n):
|
336 |
+
s = 0
|
337 |
+
while s <= k and xi[k-s] == xi[k]:
|
338 |
+
s += 1
|
339 |
+
s -= 1
|
340 |
+
Vk[0] = self.yi[k]/float_factorial(s)
|
341 |
+
for i in range(k-s):
|
342 |
+
if xi[i] == xi[k]:
|
343 |
+
raise ValueError("Elements of `xi` can't be equal.")
|
344 |
+
if s == 0:
|
345 |
+
Vk[i+1] = (c[i]-Vk[i])/(xi[i]-xi[k])
|
346 |
+
else:
|
347 |
+
Vk[i+1] = (Vk[i+1]-Vk[i])/(xi[i]-xi[k])
|
348 |
+
c[k] = Vk[k-s]
|
349 |
+
self.c = c
|
350 |
+
|
351 |
+
def _evaluate(self, x):
|
352 |
+
pi = 1
|
353 |
+
p = np.zeros((len(x), self.r), dtype=self.dtype)
|
354 |
+
p += self.c[0,np.newaxis,:]
|
355 |
+
for k in range(1, self.n):
|
356 |
+
w = x - self.xi[k-1]
|
357 |
+
pi = w*pi
|
358 |
+
p += pi[:,np.newaxis] * self.c[k]
|
359 |
+
return p
|
360 |
+
|
361 |
+
def _evaluate_derivatives(self, x, der=None):
|
362 |
+
n = self.n
|
363 |
+
r = self.r
|
364 |
+
|
365 |
+
if der is None:
|
366 |
+
der = self.n
|
367 |
+
|
368 |
+
pi = np.zeros((n, len(x)))
|
369 |
+
w = np.zeros((n, len(x)))
|
370 |
+
pi[0] = 1
|
371 |
+
p = np.zeros((len(x), self.r), dtype=self.dtype)
|
372 |
+
p += self.c[0, np.newaxis, :]
|
373 |
+
|
374 |
+
for k in range(1, n):
|
375 |
+
w[k-1] = x - self.xi[k-1]
|
376 |
+
pi[k] = w[k-1] * pi[k-1]
|
377 |
+
p += pi[k, :, np.newaxis] * self.c[k]
|
378 |
+
|
379 |
+
cn = np.zeros((max(der, n+1), len(x), r), dtype=self.dtype)
|
380 |
+
cn[:n+1, :, :] += self.c[:n+1, np.newaxis, :]
|
381 |
+
cn[0] = p
|
382 |
+
for k in range(1, n):
|
383 |
+
for i in range(1, n-k+1):
|
384 |
+
pi[i] = w[k+i-1]*pi[i-1] + pi[i]
|
385 |
+
cn[k] = cn[k] + pi[i, :, np.newaxis]*cn[k+i]
|
386 |
+
cn[k] *= float_factorial(k)
|
387 |
+
|
388 |
+
cn[n, :, :] = 0
|
389 |
+
return cn[:der]
|
390 |
+
|
391 |
+
|
392 |
+
def krogh_interpolate(xi, yi, x, der=0, axis=0):
|
393 |
+
"""
|
394 |
+
Convenience function for polynomial interpolation.
|
395 |
+
|
396 |
+
See `KroghInterpolator` for more details.
|
397 |
+
|
398 |
+
Parameters
|
399 |
+
----------
|
400 |
+
xi : array_like
|
401 |
+
Interpolation points (known x-coordinates).
|
402 |
+
yi : array_like
|
403 |
+
Known y-coordinates, of shape ``(xi.size, R)``. Interpreted as
|
404 |
+
vectors of length R, or scalars if R=1.
|
405 |
+
x : array_like
|
406 |
+
Point or points at which to evaluate the derivatives.
|
407 |
+
der : int or list or None, optional
|
408 |
+
How many derivatives to evaluate, or None for all potentially
|
409 |
+
nonzero derivatives (that is, a number equal to the number
|
410 |
+
of points), or a list of derivatives to evaluate. This number
|
411 |
+
includes the function value as the '0th' derivative.
|
412 |
+
axis : int, optional
|
413 |
+
Axis in the `yi` array corresponding to the x-coordinate values.
|
414 |
+
|
415 |
+
Returns
|
416 |
+
-------
|
417 |
+
d : ndarray
|
418 |
+
If the interpolator's values are R-D then the
|
419 |
+
returned array will be the number of derivatives by N by R.
|
420 |
+
If `x` is a scalar, the middle dimension will be dropped; if
|
421 |
+
the `yi` are scalars then the last dimension will be dropped.
|
422 |
+
|
423 |
+
See Also
|
424 |
+
--------
|
425 |
+
KroghInterpolator : Krogh interpolator
|
426 |
+
|
427 |
+
Notes
|
428 |
+
-----
|
429 |
+
Construction of the interpolating polynomial is a relatively expensive
|
430 |
+
process. If you want to evaluate it repeatedly consider using the class
|
431 |
+
KroghInterpolator (which is what this function uses).
|
432 |
+
|
433 |
+
Examples
|
434 |
+
--------
|
435 |
+
We can interpolate 2D observed data using Krogh interpolation:
|
436 |
+
|
437 |
+
>>> import numpy as np
|
438 |
+
>>> import matplotlib.pyplot as plt
|
439 |
+
>>> from scipy.interpolate import krogh_interpolate
|
440 |
+
>>> x_observed = np.linspace(0.0, 10.0, 11)
|
441 |
+
>>> y_observed = np.sin(x_observed)
|
442 |
+
>>> x = np.linspace(min(x_observed), max(x_observed), num=100)
|
443 |
+
>>> y = krogh_interpolate(x_observed, y_observed, x)
|
444 |
+
>>> plt.plot(x_observed, y_observed, "o", label="observation")
|
445 |
+
>>> plt.plot(x, y, label="krogh interpolation")
|
446 |
+
>>> plt.legend()
|
447 |
+
>>> plt.show()
|
448 |
+
"""
|
449 |
+
|
450 |
+
P = KroghInterpolator(xi, yi, axis=axis)
|
451 |
+
if der == 0:
|
452 |
+
return P(x)
|
453 |
+
elif _isscalar(der):
|
454 |
+
return P.derivative(x, der=der)
|
455 |
+
else:
|
456 |
+
return P.derivatives(x, der=np.amax(der)+1)[der]
|
457 |
+
|
458 |
+
|
459 |
+
def approximate_taylor_polynomial(f,x,degree,scale,order=None):
|
460 |
+
"""
|
461 |
+
Estimate the Taylor polynomial of f at x by polynomial fitting.
|
462 |
+
|
463 |
+
Parameters
|
464 |
+
----------
|
465 |
+
f : callable
|
466 |
+
The function whose Taylor polynomial is sought. Should accept
|
467 |
+
a vector of `x` values.
|
468 |
+
x : scalar
|
469 |
+
The point at which the polynomial is to be evaluated.
|
470 |
+
degree : int
|
471 |
+
The degree of the Taylor polynomial
|
472 |
+
scale : scalar
|
473 |
+
The width of the interval to use to evaluate the Taylor polynomial.
|
474 |
+
Function values spread over a range this wide are used to fit the
|
475 |
+
polynomial. Must be chosen carefully.
|
476 |
+
order : int or None, optional
|
477 |
+
The order of the polynomial to be used in the fitting; `f` will be
|
478 |
+
evaluated ``order+1`` times. If None, use `degree`.
|
479 |
+
|
480 |
+
Returns
|
481 |
+
-------
|
482 |
+
p : poly1d instance
|
483 |
+
The Taylor polynomial (translated to the origin, so that
|
484 |
+
for example p(0)=f(x)).
|
485 |
+
|
486 |
+
Notes
|
487 |
+
-----
|
488 |
+
The appropriate choice of "scale" is a trade-off; too large and the
|
489 |
+
function differs from its Taylor polynomial too much to get a good
|
490 |
+
answer, too small and round-off errors overwhelm the higher-order terms.
|
491 |
+
The algorithm used becomes numerically unstable around order 30 even
|
492 |
+
under ideal circumstances.
|
493 |
+
|
494 |
+
Choosing order somewhat larger than degree may improve the higher-order
|
495 |
+
terms.
|
496 |
+
|
497 |
+
Examples
|
498 |
+
--------
|
499 |
+
We can calculate Taylor approximation polynomials of sin function with
|
500 |
+
various degrees:
|
501 |
+
|
502 |
+
>>> import numpy as np
|
503 |
+
>>> import matplotlib.pyplot as plt
|
504 |
+
>>> from scipy.interpolate import approximate_taylor_polynomial
|
505 |
+
>>> x = np.linspace(-10.0, 10.0, num=100)
|
506 |
+
>>> plt.plot(x, np.sin(x), label="sin curve")
|
507 |
+
>>> for degree in np.arange(1, 15, step=2):
|
508 |
+
... sin_taylor = approximate_taylor_polynomial(np.sin, 0, degree, 1,
|
509 |
+
... order=degree + 2)
|
510 |
+
... plt.plot(x, sin_taylor(x), label=f"degree={degree}")
|
511 |
+
>>> plt.legend(bbox_to_anchor=(1.05, 1), loc='upper left',
|
512 |
+
... borderaxespad=0.0, shadow=True)
|
513 |
+
>>> plt.tight_layout()
|
514 |
+
>>> plt.axis([-10, 10, -10, 10])
|
515 |
+
>>> plt.show()
|
516 |
+
|
517 |
+
"""
|
518 |
+
if order is None:
|
519 |
+
order = degree
|
520 |
+
|
521 |
+
n = order+1
|
522 |
+
# Choose n points that cluster near the endpoints of the interval in
|
523 |
+
# a way that avoids the Runge phenomenon. Ensure, by including the
|
524 |
+
# endpoint or not as appropriate, that one point always falls at x
|
525 |
+
# exactly.
|
526 |
+
xs = scale*np.cos(np.linspace(0,np.pi,n,endpoint=n % 1)) + x
|
527 |
+
|
528 |
+
P = KroghInterpolator(xs, f(xs))
|
529 |
+
d = P.derivatives(x,der=degree+1)
|
530 |
+
|
531 |
+
return np.poly1d((d/factorial(np.arange(degree+1)))[::-1])
|
532 |
+
|
533 |
+
|
534 |
+
class BarycentricInterpolator(_Interpolator1DWithDerivatives):
|
535 |
+
r"""Interpolating polynomial for a set of points.
|
536 |
+
|
537 |
+
Constructs a polynomial that passes through a given set of points.
|
538 |
+
Allows evaluation of the polynomial and all its derivatives,
|
539 |
+
efficient changing of the y-values to be interpolated,
|
540 |
+
and updating by adding more x- and y-values.
|
541 |
+
|
542 |
+
For reasons of numerical stability, this function does not compute
|
543 |
+
the coefficients of the polynomial.
|
544 |
+
|
545 |
+
The values `yi` need to be provided before the function is
|
546 |
+
evaluated, but none of the preprocessing depends on them, so rapid
|
547 |
+
updates are possible.
|
548 |
+
|
549 |
+
Parameters
|
550 |
+
----------
|
551 |
+
xi : array_like, shape (npoints, )
|
552 |
+
1-D array of x coordinates of the points the polynomial
|
553 |
+
should pass through
|
554 |
+
yi : array_like, shape (..., npoints, ...), optional
|
555 |
+
N-D array of y coordinates of the points the polynomial should pass through.
|
556 |
+
If None, the y values will be supplied later via the `set_y` method.
|
557 |
+
The length of `yi` along the interpolation axis must be equal to the length
|
558 |
+
of `xi`. Use the ``axis`` parameter to select correct axis.
|
559 |
+
axis : int, optional
|
560 |
+
Axis in the yi array corresponding to the x-coordinate values. Defaults
|
561 |
+
to ``axis=0``.
|
562 |
+
wi : array_like, optional
|
563 |
+
The barycentric weights for the chosen interpolation points `xi`.
|
564 |
+
If absent or None, the weights will be computed from `xi` (default).
|
565 |
+
This allows for the reuse of the weights `wi` if several interpolants
|
566 |
+
are being calculated using the same nodes `xi`, without re-computation.
|
567 |
+
random_state : {None, int, `numpy.random.Generator`, `numpy.random.RandomState`}, optional
|
568 |
+
If `seed` is None (or `np.random`), the `numpy.random.RandomState`
|
569 |
+
singleton is used.
|
570 |
+
If `seed` is an int, a new ``RandomState`` instance is used,
|
571 |
+
seeded with `seed`.
|
572 |
+
If `seed` is already a ``Generator`` or ``RandomState`` instance then
|
573 |
+
that instance is used.
|
574 |
+
|
575 |
+
Notes
|
576 |
+
-----
|
577 |
+
This class uses a "barycentric interpolation" method that treats
|
578 |
+
the problem as a special case of rational function interpolation.
|
579 |
+
This algorithm is quite stable, numerically, but even in a world of
|
580 |
+
exact computation, unless the x coordinates are chosen very
|
581 |
+
carefully - Chebyshev zeros (e.g., cos(i*pi/n)) are a good choice -
|
582 |
+
polynomial interpolation itself is a very ill-conditioned process
|
583 |
+
due to the Runge phenomenon.
|
584 |
+
|
585 |
+
Based on Berrut and Trefethen 2004, "Barycentric Lagrange Interpolation".
|
586 |
+
|
587 |
+
Examples
|
588 |
+
--------
|
589 |
+
To produce a quintic barycentric interpolant approximating the function
|
590 |
+
:math:`\sin x`, and its first four derivatives, using six randomly-spaced
|
591 |
+
nodes in :math:`(0, \frac{\pi}{2})`:
|
592 |
+
|
593 |
+
>>> import numpy as np
|
594 |
+
>>> import matplotlib.pyplot as plt
|
595 |
+
>>> from scipy.interpolate import BarycentricInterpolator
|
596 |
+
>>> rng = np.random.default_rng()
|
597 |
+
>>> xi = rng.random(6) * np.pi/2
|
598 |
+
>>> f, f_d1, f_d2, f_d3, f_d4 = np.sin, np.cos, lambda x: -np.sin(x), lambda x: -np.cos(x), np.sin
|
599 |
+
>>> P = BarycentricInterpolator(xi, f(xi), random_state=rng)
|
600 |
+
>>> fig, axs = plt.subplots(5, 1, sharex=True, layout='constrained', figsize=(7,10))
|
601 |
+
>>> x = np.linspace(0, np.pi, 100)
|
602 |
+
>>> axs[0].plot(x, P(x), 'r:', x, f(x), 'k--', xi, f(xi), 'xk')
|
603 |
+
>>> axs[1].plot(x, P.derivative(x), 'r:', x, f_d1(x), 'k--', xi, f_d1(xi), 'xk')
|
604 |
+
>>> axs[2].plot(x, P.derivative(x, 2), 'r:', x, f_d2(x), 'k--', xi, f_d2(xi), 'xk')
|
605 |
+
>>> axs[3].plot(x, P.derivative(x, 3), 'r:', x, f_d3(x), 'k--', xi, f_d3(xi), 'xk')
|
606 |
+
>>> axs[4].plot(x, P.derivative(x, 4), 'r:', x, f_d4(x), 'k--', xi, f_d4(xi), 'xk')
|
607 |
+
>>> axs[0].set_xlim(0, np.pi)
|
608 |
+
>>> axs[4].set_xlabel(r"$x$")
|
609 |
+
>>> axs[4].set_xticks([i * np.pi / 4 for i in range(5)],
|
610 |
+
... ["0", r"$\frac{\pi}{4}$", r"$\frac{\pi}{2}$", r"$\frac{3\pi}{4}$", r"$\pi$"])
|
611 |
+
>>> axs[0].set_ylabel("$f(x)$")
|
612 |
+
>>> axs[1].set_ylabel("$f'(x)$")
|
613 |
+
>>> axs[2].set_ylabel("$f''(x)$")
|
614 |
+
>>> axs[3].set_ylabel("$f^{(3)}(x)$")
|
615 |
+
>>> axs[4].set_ylabel("$f^{(4)}(x)$")
|
616 |
+
>>> labels = ['Interpolation nodes', 'True function $f$', 'Barycentric interpolation']
|
617 |
+
>>> axs[0].legend(axs[0].get_lines()[::-1], labels, bbox_to_anchor=(0., 1.02, 1., .102),
|
618 |
+
... loc='lower left', ncols=3, mode="expand", borderaxespad=0., frameon=False)
|
619 |
+
>>> plt.show()
|
620 |
+
""" # numpy/numpydoc#87 # noqa: E501
|
621 |
+
|
622 |
+
def __init__(self, xi, yi=None, axis=0, *, wi=None, random_state=None):
|
623 |
+
super().__init__(xi, yi, axis)
|
624 |
+
|
625 |
+
random_state = check_random_state(random_state)
|
626 |
+
|
627 |
+
self.xi = np.asarray(xi, dtype=np.float64)
|
628 |
+
self.set_yi(yi)
|
629 |
+
self.n = len(self.xi)
|
630 |
+
|
631 |
+
# cache derivative object to avoid re-computing the weights with every call.
|
632 |
+
self._diff_cij = None
|
633 |
+
|
634 |
+
if wi is not None:
|
635 |
+
self.wi = wi
|
636 |
+
else:
|
637 |
+
# See page 510 of Berrut and Trefethen 2004 for an explanation of the
|
638 |
+
# capacity scaling and the suggestion of using a random permutation of
|
639 |
+
# the input factors.
|
640 |
+
# At the moment, the permutation is not performed for xi that are
|
641 |
+
# appended later through the add_xi interface. It's not clear to me how
|
642 |
+
# to implement that and it seems that most situations that require
|
643 |
+
# these numerical stability improvements will be able to provide all
|
644 |
+
# the points to the constructor.
|
645 |
+
self._inv_capacity = 4.0 / (np.max(self.xi) - np.min(self.xi))
|
646 |
+
permute = random_state.permutation(self.n, )
|
647 |
+
inv_permute = np.zeros(self.n, dtype=np.int32)
|
648 |
+
inv_permute[permute] = np.arange(self.n)
|
649 |
+
self.wi = np.zeros(self.n)
|
650 |
+
|
651 |
+
for i in range(self.n):
|
652 |
+
dist = self._inv_capacity * (self.xi[i] - self.xi[permute])
|
653 |
+
dist[inv_permute[i]] = 1.0
|
654 |
+
prod = np.prod(dist)
|
655 |
+
if prod == 0.0:
|
656 |
+
raise ValueError("Interpolation points xi must be"
|
657 |
+
" distinct.")
|
658 |
+
self.wi[i] = 1.0 / prod
|
659 |
+
|
660 |
+
def set_yi(self, yi, axis=None):
|
661 |
+
"""
|
662 |
+
Update the y values to be interpolated
|
663 |
+
|
664 |
+
The barycentric interpolation algorithm requires the calculation
|
665 |
+
of weights, but these depend only on the `xi`. The `yi` can be changed
|
666 |
+
at any time.
|
667 |
+
|
668 |
+
Parameters
|
669 |
+
----------
|
670 |
+
yi : array_like
|
671 |
+
The y-coordinates of the points the polynomial will pass through.
|
672 |
+
If None, the y values must be supplied later.
|
673 |
+
axis : int, optional
|
674 |
+
Axis in the `yi` array corresponding to the x-coordinate values.
|
675 |
+
|
676 |
+
"""
|
677 |
+
if yi is None:
|
678 |
+
self.yi = None
|
679 |
+
return
|
680 |
+
self._set_yi(yi, xi=self.xi, axis=axis)
|
681 |
+
self.yi = self._reshape_yi(yi)
|
682 |
+
self.n, self.r = self.yi.shape
|
683 |
+
self._diff_baryint = None
|
684 |
+
|
685 |
+
def add_xi(self, xi, yi=None):
|
686 |
+
"""
|
687 |
+
Add more x values to the set to be interpolated
|
688 |
+
|
689 |
+
The barycentric interpolation algorithm allows easy updating by
|
690 |
+
adding more points for the polynomial to pass through.
|
691 |
+
|
692 |
+
Parameters
|
693 |
+
----------
|
694 |
+
xi : array_like
|
695 |
+
The x coordinates of the points that the polynomial should pass
|
696 |
+
through.
|
697 |
+
yi : array_like, optional
|
698 |
+
The y coordinates of the points the polynomial should pass through.
|
699 |
+
Should have shape ``(xi.size, R)``; if R > 1 then the polynomial is
|
700 |
+
vector-valued.
|
701 |
+
If `yi` is not given, the y values will be supplied later. `yi`
|
702 |
+
should be given if and only if the interpolator has y values
|
703 |
+
specified.
|
704 |
+
|
705 |
+
Notes
|
706 |
+
-----
|
707 |
+
The new points added by `add_xi` are not randomly permuted
|
708 |
+
so there is potential for numerical instability,
|
709 |
+
especially for a large number of points. If this
|
710 |
+
happens, please reconstruct interpolation from scratch instead.
|
711 |
+
"""
|
712 |
+
if yi is not None:
|
713 |
+
if self.yi is None:
|
714 |
+
raise ValueError("No previous yi value to update!")
|
715 |
+
yi = self._reshape_yi(yi, check=True)
|
716 |
+
self.yi = np.vstack((self.yi,yi))
|
717 |
+
else:
|
718 |
+
if self.yi is not None:
|
719 |
+
raise ValueError("No update to yi provided!")
|
720 |
+
old_n = self.n
|
721 |
+
self.xi = np.concatenate((self.xi,xi))
|
722 |
+
self.n = len(self.xi)
|
723 |
+
self.wi **= -1
|
724 |
+
old_wi = self.wi
|
725 |
+
self.wi = np.zeros(self.n)
|
726 |
+
self.wi[:old_n] = old_wi
|
727 |
+
for j in range(old_n, self.n):
|
728 |
+
self.wi[:j] *= self._inv_capacity * (self.xi[j]-self.xi[:j])
|
729 |
+
self.wi[j] = np.multiply.reduce(
|
730 |
+
self._inv_capacity * (self.xi[:j]-self.xi[j])
|
731 |
+
)
|
732 |
+
self.wi **= -1
|
733 |
+
self._diff_cij = None
|
734 |
+
self._diff_baryint = None
|
735 |
+
|
736 |
+
def __call__(self, x):
|
737 |
+
"""Evaluate the interpolating polynomial at the points x
|
738 |
+
|
739 |
+
Parameters
|
740 |
+
----------
|
741 |
+
x : array_like
|
742 |
+
Point or points at which to evaluate the interpolant.
|
743 |
+
|
744 |
+
Returns
|
745 |
+
-------
|
746 |
+
y : array_like
|
747 |
+
Interpolated values. Shape is determined by replacing
|
748 |
+
the interpolation axis in the original array with the shape of `x`.
|
749 |
+
|
750 |
+
Notes
|
751 |
+
-----
|
752 |
+
Currently the code computes an outer product between `x` and the
|
753 |
+
weights, that is, it constructs an intermediate array of size
|
754 |
+
``(N, len(x))``, where N is the degree of the polynomial.
|
755 |
+
"""
|
756 |
+
return _Interpolator1D.__call__(self, x)
|
757 |
+
|
758 |
+
def _evaluate(self, x):
|
759 |
+
if x.size == 0:
|
760 |
+
p = np.zeros((0, self.r), dtype=self.dtype)
|
761 |
+
else:
|
762 |
+
c = x[..., np.newaxis] - self.xi
|
763 |
+
z = c == 0
|
764 |
+
c[z] = 1
|
765 |
+
c = self.wi / c
|
766 |
+
with np.errstate(divide='ignore'):
|
767 |
+
p = np.dot(c, self.yi) / np.sum(c, axis=-1)[..., np.newaxis]
|
768 |
+
# Now fix where x==some xi
|
769 |
+
r = np.nonzero(z)
|
770 |
+
if len(r) == 1: # evaluation at a scalar
|
771 |
+
if len(r[0]) > 0: # equals one of the points
|
772 |
+
p = self.yi[r[0][0]]
|
773 |
+
else:
|
774 |
+
p[r[:-1]] = self.yi[r[-1]]
|
775 |
+
return p
|
776 |
+
|
777 |
+
def derivative(self, x, der=1):
|
778 |
+
"""
|
779 |
+
Evaluate a single derivative of the polynomial at the point x.
|
780 |
+
|
781 |
+
Parameters
|
782 |
+
----------
|
783 |
+
x : array_like
|
784 |
+
Point or points at which to evaluate the derivatives
|
785 |
+
der : integer, optional
|
786 |
+
Which derivative to evaluate (default: first derivative).
|
787 |
+
This number includes the function value as 0th derivative.
|
788 |
+
|
789 |
+
Returns
|
790 |
+
-------
|
791 |
+
d : ndarray
|
792 |
+
Derivative interpolated at the x-points. Shape of `d` is
|
793 |
+
determined by replacing the interpolation axis in the
|
794 |
+
original array with the shape of `x`.
|
795 |
+
"""
|
796 |
+
x, x_shape = self._prepare_x(x)
|
797 |
+
y = self._evaluate_derivatives(x, der+1, all_lower=False)
|
798 |
+
return self._finish_y(y, x_shape)
|
799 |
+
|
800 |
+
def _evaluate_derivatives(self, x, der=None, all_lower=True):
|
801 |
+
# NB: der here is not the order of the highest derivative;
|
802 |
+
# instead, it is the size of the derivatives matrix that
|
803 |
+
# would be returned with all_lower=True, including the
|
804 |
+
# '0th' derivative (the undifferentiated function).
|
805 |
+
# E.g. to evaluate the 5th derivative alone, call
|
806 |
+
# _evaluate_derivatives(x, der=6, all_lower=False).
|
807 |
+
|
808 |
+
if (not all_lower) and (x.size == 0 or self.r == 0):
|
809 |
+
return np.zeros((0, self.r), dtype=self.dtype)
|
810 |
+
|
811 |
+
if (not all_lower) and der == 1:
|
812 |
+
return self._evaluate(x)
|
813 |
+
|
814 |
+
if (not all_lower) and (der > self.n):
|
815 |
+
return np.zeros((len(x), self.r), dtype=self.dtype)
|
816 |
+
|
817 |
+
if der is None:
|
818 |
+
der = self.n
|
819 |
+
|
820 |
+
if all_lower and (x.size == 0 or self.r == 0):
|
821 |
+
return np.zeros((der, len(x), self.r), dtype=self.dtype)
|
822 |
+
|
823 |
+
if self._diff_cij is None:
|
824 |
+
# c[i,j] = xi[i] - xi[j]
|
825 |
+
c = self.xi[:, np.newaxis] - self.xi
|
826 |
+
|
827 |
+
# avoid division by 0 (diagonal entries are so far zero by construction)
|
828 |
+
np.fill_diagonal(c, 1)
|
829 |
+
|
830 |
+
# c[i,j] = (w[j] / w[i]) / (xi[i] - xi[j]) (equation 9.4)
|
831 |
+
c = self.wi/ (c * self.wi[..., np.newaxis])
|
832 |
+
|
833 |
+
# fill in correct diagonal entries: each column sums to 0
|
834 |
+
np.fill_diagonal(c, 0)
|
835 |
+
|
836 |
+
# calculate diagonal
|
837 |
+
# c[j,j] = -sum_{i != j} c[i,j] (equation 9.5)
|
838 |
+
d = -c.sum(axis=1)
|
839 |
+
# c[i,j] = l_j(x_i)
|
840 |
+
np.fill_diagonal(c, d)
|
841 |
+
|
842 |
+
self._diff_cij = c
|
843 |
+
|
844 |
+
if self._diff_baryint is None:
|
845 |
+
# initialise and cache derivative interpolator and cijs;
|
846 |
+
# reuse weights wi (which depend only on interpolation points xi),
|
847 |
+
# to avoid unnecessary re-computation
|
848 |
+
self._diff_baryint = BarycentricInterpolator(xi=self.xi,
|
849 |
+
yi=self._diff_cij @ self.yi,
|
850 |
+
wi=self.wi)
|
851 |
+
self._diff_baryint._diff_cij = self._diff_cij
|
852 |
+
|
853 |
+
if all_lower:
|
854 |
+
# assemble matrix of derivatives from order 0 to order der-1,
|
855 |
+
# in the format required by _Interpolator1DWithDerivatives.
|
856 |
+
cn = np.zeros((der, len(x), self.r), dtype=self.dtype)
|
857 |
+
for d in range(der):
|
858 |
+
cn[d, :, :] = self._evaluate_derivatives(x, d+1, all_lower=False)
|
859 |
+
return cn
|
860 |
+
|
861 |
+
# recursively evaluate only the derivative requested
|
862 |
+
return self._diff_baryint._evaluate_derivatives(x, der-1, all_lower=False)
|
863 |
+
|
864 |
+
|
865 |
+
def barycentric_interpolate(xi, yi, x, axis=0, *, der=0):
|
866 |
+
"""
|
867 |
+
Convenience function for polynomial interpolation.
|
868 |
+
|
869 |
+
Constructs a polynomial that passes through a given set of points,
|
870 |
+
then evaluates the polynomial. For reasons of numerical stability,
|
871 |
+
this function does not compute the coefficients of the polynomial.
|
872 |
+
|
873 |
+
This function uses a "barycentric interpolation" method that treats
|
874 |
+
the problem as a special case of rational function interpolation.
|
875 |
+
This algorithm is quite stable, numerically, but even in a world of
|
876 |
+
exact computation, unless the `x` coordinates are chosen very
|
877 |
+
carefully - Chebyshev zeros (e.g., cos(i*pi/n)) are a good choice -
|
878 |
+
polynomial interpolation itself is a very ill-conditioned process
|
879 |
+
due to the Runge phenomenon.
|
880 |
+
|
881 |
+
Parameters
|
882 |
+
----------
|
883 |
+
xi : array_like
|
884 |
+
1-D array of x coordinates of the points the polynomial should
|
885 |
+
pass through
|
886 |
+
yi : array_like
|
887 |
+
The y coordinates of the points the polynomial should pass through.
|
888 |
+
x : scalar or array_like
|
889 |
+
Point or points at which to evaluate the interpolant.
|
890 |
+
der : int or list or None, optional
|
891 |
+
How many derivatives to evaluate, or None for all potentially
|
892 |
+
nonzero derivatives (that is, a number equal to the number
|
893 |
+
of points), or a list of derivatives to evaluate. This number
|
894 |
+
includes the function value as the '0th' derivative.
|
895 |
+
axis : int, optional
|
896 |
+
Axis in the `yi` array corresponding to the x-coordinate values.
|
897 |
+
|
898 |
+
Returns
|
899 |
+
-------
|
900 |
+
y : scalar or array_like
|
901 |
+
Interpolated values. Shape is determined by replacing
|
902 |
+
the interpolation axis in the original array with the shape of `x`.
|
903 |
+
|
904 |
+
See Also
|
905 |
+
--------
|
906 |
+
BarycentricInterpolator : Barycentric interpolator
|
907 |
+
|
908 |
+
Notes
|
909 |
+
-----
|
910 |
+
Construction of the interpolation weights is a relatively slow process.
|
911 |
+
If you want to call this many times with the same xi (but possibly
|
912 |
+
varying yi or x) you should use the class `BarycentricInterpolator`.
|
913 |
+
This is what this function uses internally.
|
914 |
+
|
915 |
+
Examples
|
916 |
+
--------
|
917 |
+
We can interpolate 2D observed data using barycentric interpolation:
|
918 |
+
|
919 |
+
>>> import numpy as np
|
920 |
+
>>> import matplotlib.pyplot as plt
|
921 |
+
>>> from scipy.interpolate import barycentric_interpolate
|
922 |
+
>>> x_observed = np.linspace(0.0, 10.0, 11)
|
923 |
+
>>> y_observed = np.sin(x_observed)
|
924 |
+
>>> x = np.linspace(min(x_observed), max(x_observed), num=100)
|
925 |
+
>>> y = barycentric_interpolate(x_observed, y_observed, x)
|
926 |
+
>>> plt.plot(x_observed, y_observed, "o", label="observation")
|
927 |
+
>>> plt.plot(x, y, label="barycentric interpolation")
|
928 |
+
>>> plt.legend()
|
929 |
+
>>> plt.show()
|
930 |
+
|
931 |
+
"""
|
932 |
+
P = BarycentricInterpolator(xi, yi, axis=axis)
|
933 |
+
if der == 0:
|
934 |
+
return P(x)
|
935 |
+
elif _isscalar(der):
|
936 |
+
return P.derivative(x, der=der)
|
937 |
+
else:
|
938 |
+
return P.derivatives(x, der=np.amax(der)+1)[der]
|
env-llmeval/lib/python3.10/site-packages/scipy/interpolate/_rbf.py
ADDED
@@ -0,0 +1,290 @@
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
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|
|
|
1 |
+
"""rbf - Radial basis functions for interpolation/smoothing scattered N-D data.
|
2 |
+
|
3 |
+
Written by John Travers <[email protected]>, February 2007
|
4 |
+
Based closely on Matlab code by Alex Chirokov
|
5 |
+
Additional, large, improvements by Robert Hetland
|
6 |
+
Some additional alterations by Travis Oliphant
|
7 |
+
Interpolation with multi-dimensional target domain by Josua Sassen
|
8 |
+
|
9 |
+
Permission to use, modify, and distribute this software is given under the
|
10 |
+
terms of the SciPy (BSD style) license. See LICENSE.txt that came with
|
11 |
+
this distribution for specifics.
|
12 |
+
|
13 |
+
NO WARRANTY IS EXPRESSED OR IMPLIED. USE AT YOUR OWN RISK.
|
14 |
+
|
15 |
+
Copyright (c) 2006-2007, Robert Hetland <[email protected]>
|
16 |
+
Copyright (c) 2007, John Travers <[email protected]>
|
17 |
+
|
18 |
+
Redistribution and use in source and binary forms, with or without
|
19 |
+
modification, are permitted provided that the following conditions are
|
20 |
+
met:
|
21 |
+
|
22 |
+
* Redistributions of source code must retain the above copyright
|
23 |
+
notice, this list of conditions and the following disclaimer.
|
24 |
+
|
25 |
+
* Redistributions in binary form must reproduce the above
|
26 |
+
copyright notice, this list of conditions and the following
|
27 |
+
disclaimer in the documentation and/or other materials provided
|
28 |
+
with the distribution.
|
29 |
+
|
30 |
+
* Neither the name of Robert Hetland nor the names of any
|
31 |
+
contributors may be used to endorse or promote products derived
|
32 |
+
from this software without specific prior written permission.
|
33 |
+
|
34 |
+
THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
|
35 |
+
"AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
|
36 |
+
LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
|
37 |
+
A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
|
38 |
+
OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
|
39 |
+
SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
|
40 |
+
LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
|
41 |
+
DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
|
42 |
+
THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
|
43 |
+
(INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
|
44 |
+
OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
|
45 |
+
"""
|
46 |
+
import numpy as np
|
47 |
+
|
48 |
+
from scipy import linalg
|
49 |
+
from scipy.special import xlogy
|
50 |
+
from scipy.spatial.distance import cdist, pdist, squareform
|
51 |
+
|
52 |
+
__all__ = ['Rbf']
|
53 |
+
|
54 |
+
|
55 |
+
class Rbf:
|
56 |
+
"""
|
57 |
+
Rbf(*args, **kwargs)
|
58 |
+
|
59 |
+
A class for radial basis function interpolation of functions from
|
60 |
+
N-D scattered data to an M-D domain.
|
61 |
+
|
62 |
+
.. legacy:: class
|
63 |
+
|
64 |
+
`Rbf` is legacy code, for new usage please use `RBFInterpolator`
|
65 |
+
instead.
|
66 |
+
|
67 |
+
Parameters
|
68 |
+
----------
|
69 |
+
*args : arrays
|
70 |
+
x, y, z, ..., d, where x, y, z, ... are the coordinates of the nodes
|
71 |
+
and d is the array of values at the nodes
|
72 |
+
function : str or callable, optional
|
73 |
+
The radial basis function, based on the radius, r, given by the norm
|
74 |
+
(default is Euclidean distance); the default is 'multiquadric'::
|
75 |
+
|
76 |
+
'multiquadric': sqrt((r/self.epsilon)**2 + 1)
|
77 |
+
'inverse': 1.0/sqrt((r/self.epsilon)**2 + 1)
|
78 |
+
'gaussian': exp(-(r/self.epsilon)**2)
|
79 |
+
'linear': r
|
80 |
+
'cubic': r**3
|
81 |
+
'quintic': r**5
|
82 |
+
'thin_plate': r**2 * log(r)
|
83 |
+
|
84 |
+
If callable, then it must take 2 arguments (self, r). The epsilon
|
85 |
+
parameter will be available as self.epsilon. Other keyword
|
86 |
+
arguments passed in will be available as well.
|
87 |
+
|
88 |
+
epsilon : float, optional
|
89 |
+
Adjustable constant for gaussian or multiquadrics functions
|
90 |
+
- defaults to approximate average distance between nodes (which is
|
91 |
+
a good start).
|
92 |
+
smooth : float, optional
|
93 |
+
Values greater than zero increase the smoothness of the
|
94 |
+
approximation. 0 is for interpolation (default), the function will
|
95 |
+
always go through the nodal points in this case.
|
96 |
+
norm : str, callable, optional
|
97 |
+
A function that returns the 'distance' between two points, with
|
98 |
+
inputs as arrays of positions (x, y, z, ...), and an output as an
|
99 |
+
array of distance. E.g., the default: 'euclidean', such that the result
|
100 |
+
is a matrix of the distances from each point in ``x1`` to each point in
|
101 |
+
``x2``. For more options, see documentation of
|
102 |
+
`scipy.spatial.distances.cdist`.
|
103 |
+
mode : str, optional
|
104 |
+
Mode of the interpolation, can be '1-D' (default) or 'N-D'. When it is
|
105 |
+
'1-D' the data `d` will be considered as 1-D and flattened
|
106 |
+
internally. When it is 'N-D' the data `d` is assumed to be an array of
|
107 |
+
shape (n_samples, m), where m is the dimension of the target domain.
|
108 |
+
|
109 |
+
|
110 |
+
Attributes
|
111 |
+
----------
|
112 |
+
N : int
|
113 |
+
The number of data points (as determined by the input arrays).
|
114 |
+
di : ndarray
|
115 |
+
The 1-D array of data values at each of the data coordinates `xi`.
|
116 |
+
xi : ndarray
|
117 |
+
The 2-D array of data coordinates.
|
118 |
+
function : str or callable
|
119 |
+
The radial basis function. See description under Parameters.
|
120 |
+
epsilon : float
|
121 |
+
Parameter used by gaussian or multiquadrics functions. See Parameters.
|
122 |
+
smooth : float
|
123 |
+
Smoothing parameter. See description under Parameters.
|
124 |
+
norm : str or callable
|
125 |
+
The distance function. See description under Parameters.
|
126 |
+
mode : str
|
127 |
+
Mode of the interpolation. See description under Parameters.
|
128 |
+
nodes : ndarray
|
129 |
+
A 1-D array of node values for the interpolation.
|
130 |
+
A : internal property, do not use
|
131 |
+
|
132 |
+
See Also
|
133 |
+
--------
|
134 |
+
RBFInterpolator
|
135 |
+
|
136 |
+
Examples
|
137 |
+
--------
|
138 |
+
>>> import numpy as np
|
139 |
+
>>> from scipy.interpolate import Rbf
|
140 |
+
>>> rng = np.random.default_rng()
|
141 |
+
>>> x, y, z, d = rng.random((4, 50))
|
142 |
+
>>> rbfi = Rbf(x, y, z, d) # radial basis function interpolator instance
|
143 |
+
>>> xi = yi = zi = np.linspace(0, 1, 20)
|
144 |
+
>>> di = rbfi(xi, yi, zi) # interpolated values
|
145 |
+
>>> di.shape
|
146 |
+
(20,)
|
147 |
+
|
148 |
+
"""
|
149 |
+
# Available radial basis functions that can be selected as strings;
|
150 |
+
# they all start with _h_ (self._init_function relies on that)
|
151 |
+
def _h_multiquadric(self, r):
|
152 |
+
return np.sqrt((1.0/self.epsilon*r)**2 + 1)
|
153 |
+
|
154 |
+
def _h_inverse_multiquadric(self, r):
|
155 |
+
return 1.0/np.sqrt((1.0/self.epsilon*r)**2 + 1)
|
156 |
+
|
157 |
+
def _h_gaussian(self, r):
|
158 |
+
return np.exp(-(1.0/self.epsilon*r)**2)
|
159 |
+
|
160 |
+
def _h_linear(self, r):
|
161 |
+
return r
|
162 |
+
|
163 |
+
def _h_cubic(self, r):
|
164 |
+
return r**3
|
165 |
+
|
166 |
+
def _h_quintic(self, r):
|
167 |
+
return r**5
|
168 |
+
|
169 |
+
def _h_thin_plate(self, r):
|
170 |
+
return xlogy(r**2, r)
|
171 |
+
|
172 |
+
# Setup self._function and do smoke test on initial r
|
173 |
+
def _init_function(self, r):
|
174 |
+
if isinstance(self.function, str):
|
175 |
+
self.function = self.function.lower()
|
176 |
+
_mapped = {'inverse': 'inverse_multiquadric',
|
177 |
+
'inverse multiquadric': 'inverse_multiquadric',
|
178 |
+
'thin-plate': 'thin_plate'}
|
179 |
+
if self.function in _mapped:
|
180 |
+
self.function = _mapped[self.function]
|
181 |
+
|
182 |
+
func_name = "_h_" + self.function
|
183 |
+
if hasattr(self, func_name):
|
184 |
+
self._function = getattr(self, func_name)
|
185 |
+
else:
|
186 |
+
functionlist = [x[3:] for x in dir(self)
|
187 |
+
if x.startswith('_h_')]
|
188 |
+
raise ValueError("function must be a callable or one of " +
|
189 |
+
", ".join(functionlist))
|
190 |
+
self._function = getattr(self, "_h_"+self.function)
|
191 |
+
elif callable(self.function):
|
192 |
+
allow_one = False
|
193 |
+
if hasattr(self.function, 'func_code') or \
|
194 |
+
hasattr(self.function, '__code__'):
|
195 |
+
val = self.function
|
196 |
+
allow_one = True
|
197 |
+
elif hasattr(self.function, "__call__"):
|
198 |
+
val = self.function.__call__.__func__
|
199 |
+
else:
|
200 |
+
raise ValueError("Cannot determine number of arguments to "
|
201 |
+
"function")
|
202 |
+
|
203 |
+
argcount = val.__code__.co_argcount
|
204 |
+
if allow_one and argcount == 1:
|
205 |
+
self._function = self.function
|
206 |
+
elif argcount == 2:
|
207 |
+
self._function = self.function.__get__(self, Rbf)
|
208 |
+
else:
|
209 |
+
raise ValueError("Function argument must take 1 or 2 "
|
210 |
+
"arguments.")
|
211 |
+
|
212 |
+
a0 = self._function(r)
|
213 |
+
if a0.shape != r.shape:
|
214 |
+
raise ValueError("Callable must take array and return array of "
|
215 |
+
"the same shape")
|
216 |
+
return a0
|
217 |
+
|
218 |
+
def __init__(self, *args, **kwargs):
|
219 |
+
# `args` can be a variable number of arrays; we flatten them and store
|
220 |
+
# them as a single 2-D array `xi` of shape (n_args-1, array_size),
|
221 |
+
# plus a 1-D array `di` for the values.
|
222 |
+
# All arrays must have the same number of elements
|
223 |
+
self.xi = np.asarray([np.asarray(a, dtype=np.float64).flatten()
|
224 |
+
for a in args[:-1]])
|
225 |
+
self.N = self.xi.shape[-1]
|
226 |
+
|
227 |
+
self.mode = kwargs.pop('mode', '1-D')
|
228 |
+
|
229 |
+
if self.mode == '1-D':
|
230 |
+
self.di = np.asarray(args[-1]).flatten()
|
231 |
+
self._target_dim = 1
|
232 |
+
elif self.mode == 'N-D':
|
233 |
+
self.di = np.asarray(args[-1])
|
234 |
+
self._target_dim = self.di.shape[-1]
|
235 |
+
else:
|
236 |
+
raise ValueError("Mode has to be 1-D or N-D.")
|
237 |
+
|
238 |
+
if not all([x.size == self.di.shape[0] for x in self.xi]):
|
239 |
+
raise ValueError("All arrays must be equal length.")
|
240 |
+
|
241 |
+
self.norm = kwargs.pop('norm', 'euclidean')
|
242 |
+
self.epsilon = kwargs.pop('epsilon', None)
|
243 |
+
if self.epsilon is None:
|
244 |
+
# default epsilon is the "the average distance between nodes" based
|
245 |
+
# on a bounding hypercube
|
246 |
+
ximax = np.amax(self.xi, axis=1)
|
247 |
+
ximin = np.amin(self.xi, axis=1)
|
248 |
+
edges = ximax - ximin
|
249 |
+
edges = edges[np.nonzero(edges)]
|
250 |
+
self.epsilon = np.power(np.prod(edges)/self.N, 1.0/edges.size)
|
251 |
+
|
252 |
+
self.smooth = kwargs.pop('smooth', 0.0)
|
253 |
+
self.function = kwargs.pop('function', 'multiquadric')
|
254 |
+
|
255 |
+
# attach anything left in kwargs to self for use by any user-callable
|
256 |
+
# function or to save on the object returned.
|
257 |
+
for item, value in kwargs.items():
|
258 |
+
setattr(self, item, value)
|
259 |
+
|
260 |
+
# Compute weights
|
261 |
+
if self._target_dim > 1: # If we have more than one target dimension,
|
262 |
+
# we first factorize the matrix
|
263 |
+
self.nodes = np.zeros((self.N, self._target_dim), dtype=self.di.dtype)
|
264 |
+
lu, piv = linalg.lu_factor(self.A)
|
265 |
+
for i in range(self._target_dim):
|
266 |
+
self.nodes[:, i] = linalg.lu_solve((lu, piv), self.di[:, i])
|
267 |
+
else:
|
268 |
+
self.nodes = linalg.solve(self.A, self.di)
|
269 |
+
|
270 |
+
@property
|
271 |
+
def A(self):
|
272 |
+
# this only exists for backwards compatibility: self.A was available
|
273 |
+
# and, at least technically, public.
|
274 |
+
r = squareform(pdist(self.xi.T, self.norm)) # Pairwise norm
|
275 |
+
return self._init_function(r) - np.eye(self.N)*self.smooth
|
276 |
+
|
277 |
+
def _call_norm(self, x1, x2):
|
278 |
+
return cdist(x1.T, x2.T, self.norm)
|
279 |
+
|
280 |
+
def __call__(self, *args):
|
281 |
+
args = [np.asarray(x) for x in args]
|
282 |
+
if not all([x.shape == y.shape for x in args for y in args]):
|
283 |
+
raise ValueError("Array lengths must be equal")
|
284 |
+
if self._target_dim > 1:
|
285 |
+
shp = args[0].shape + (self._target_dim,)
|
286 |
+
else:
|
287 |
+
shp = args[0].shape
|
288 |
+
xa = np.asarray([a.flatten() for a in args], dtype=np.float64)
|
289 |
+
r = self._call_norm(xa, self.xi)
|
290 |
+
return np.dot(self._function(r), self.nodes).reshape(shp)
|
env-llmeval/lib/python3.10/site-packages/scipy/interpolate/_rbfinterp.py
ADDED
@@ -0,0 +1,550 @@
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
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|
1 |
+
"""Module for RBF interpolation."""
|
2 |
+
import warnings
|
3 |
+
from itertools import combinations_with_replacement
|
4 |
+
|
5 |
+
import numpy as np
|
6 |
+
from numpy.linalg import LinAlgError
|
7 |
+
from scipy.spatial import KDTree
|
8 |
+
from scipy.special import comb
|
9 |
+
from scipy.linalg.lapack import dgesv # type: ignore[attr-defined]
|
10 |
+
|
11 |
+
from ._rbfinterp_pythran import (_build_system,
|
12 |
+
_build_evaluation_coefficients,
|
13 |
+
_polynomial_matrix)
|
14 |
+
|
15 |
+
|
16 |
+
__all__ = ["RBFInterpolator"]
|
17 |
+
|
18 |
+
|
19 |
+
# These RBFs are implemented.
|
20 |
+
_AVAILABLE = {
|
21 |
+
"linear",
|
22 |
+
"thin_plate_spline",
|
23 |
+
"cubic",
|
24 |
+
"quintic",
|
25 |
+
"multiquadric",
|
26 |
+
"inverse_multiquadric",
|
27 |
+
"inverse_quadratic",
|
28 |
+
"gaussian"
|
29 |
+
}
|
30 |
+
|
31 |
+
|
32 |
+
# The shape parameter does not need to be specified when using these RBFs.
|
33 |
+
_SCALE_INVARIANT = {"linear", "thin_plate_spline", "cubic", "quintic"}
|
34 |
+
|
35 |
+
|
36 |
+
# For RBFs that are conditionally positive definite of order m, the interpolant
|
37 |
+
# should include polynomial terms with degree >= m - 1. Define the minimum
|
38 |
+
# degrees here. These values are from Chapter 8 of Fasshauer's "Meshfree
|
39 |
+
# Approximation Methods with MATLAB". The RBFs that are not in this dictionary
|
40 |
+
# are positive definite and do not need polynomial terms.
|
41 |
+
_NAME_TO_MIN_DEGREE = {
|
42 |
+
"multiquadric": 0,
|
43 |
+
"linear": 0,
|
44 |
+
"thin_plate_spline": 1,
|
45 |
+
"cubic": 1,
|
46 |
+
"quintic": 2
|
47 |
+
}
|
48 |
+
|
49 |
+
|
50 |
+
def _monomial_powers(ndim, degree):
|
51 |
+
"""Return the powers for each monomial in a polynomial.
|
52 |
+
|
53 |
+
Parameters
|
54 |
+
----------
|
55 |
+
ndim : int
|
56 |
+
Number of variables in the polynomial.
|
57 |
+
degree : int
|
58 |
+
Degree of the polynomial.
|
59 |
+
|
60 |
+
Returns
|
61 |
+
-------
|
62 |
+
(nmonos, ndim) int ndarray
|
63 |
+
Array where each row contains the powers for each variable in a
|
64 |
+
monomial.
|
65 |
+
|
66 |
+
"""
|
67 |
+
nmonos = comb(degree + ndim, ndim, exact=True)
|
68 |
+
out = np.zeros((nmonos, ndim), dtype=np.dtype("long"))
|
69 |
+
count = 0
|
70 |
+
for deg in range(degree + 1):
|
71 |
+
for mono in combinations_with_replacement(range(ndim), deg):
|
72 |
+
# `mono` is a tuple of variables in the current monomial with
|
73 |
+
# multiplicity indicating power (e.g., (0, 1, 1) represents x*y**2)
|
74 |
+
for var in mono:
|
75 |
+
out[count, var] += 1
|
76 |
+
|
77 |
+
count += 1
|
78 |
+
|
79 |
+
return out
|
80 |
+
|
81 |
+
|
82 |
+
def _build_and_solve_system(y, d, smoothing, kernel, epsilon, powers):
|
83 |
+
"""Build and solve the RBF interpolation system of equations.
|
84 |
+
|
85 |
+
Parameters
|
86 |
+
----------
|
87 |
+
y : (P, N) float ndarray
|
88 |
+
Data point coordinates.
|
89 |
+
d : (P, S) float ndarray
|
90 |
+
Data values at `y`.
|
91 |
+
smoothing : (P,) float ndarray
|
92 |
+
Smoothing parameter for each data point.
|
93 |
+
kernel : str
|
94 |
+
Name of the RBF.
|
95 |
+
epsilon : float
|
96 |
+
Shape parameter.
|
97 |
+
powers : (R, N) int ndarray
|
98 |
+
The exponents for each monomial in the polynomial.
|
99 |
+
|
100 |
+
Returns
|
101 |
+
-------
|
102 |
+
coeffs : (P + R, S) float ndarray
|
103 |
+
Coefficients for each RBF and monomial.
|
104 |
+
shift : (N,) float ndarray
|
105 |
+
Domain shift used to create the polynomial matrix.
|
106 |
+
scale : (N,) float ndarray
|
107 |
+
Domain scaling used to create the polynomial matrix.
|
108 |
+
|
109 |
+
"""
|
110 |
+
lhs, rhs, shift, scale = _build_system(
|
111 |
+
y, d, smoothing, kernel, epsilon, powers
|
112 |
+
)
|
113 |
+
_, _, coeffs, info = dgesv(lhs, rhs, overwrite_a=True, overwrite_b=True)
|
114 |
+
if info < 0:
|
115 |
+
raise ValueError(f"The {-info}-th argument had an illegal value.")
|
116 |
+
elif info > 0:
|
117 |
+
msg = "Singular matrix."
|
118 |
+
nmonos = powers.shape[0]
|
119 |
+
if nmonos > 0:
|
120 |
+
pmat = _polynomial_matrix((y - shift)/scale, powers)
|
121 |
+
rank = np.linalg.matrix_rank(pmat)
|
122 |
+
if rank < nmonos:
|
123 |
+
msg = (
|
124 |
+
"Singular matrix. The matrix of monomials evaluated at "
|
125 |
+
"the data point coordinates does not have full column "
|
126 |
+
f"rank ({rank}/{nmonos})."
|
127 |
+
)
|
128 |
+
|
129 |
+
raise LinAlgError(msg)
|
130 |
+
|
131 |
+
return shift, scale, coeffs
|
132 |
+
|
133 |
+
|
134 |
+
class RBFInterpolator:
|
135 |
+
"""Radial basis function (RBF) interpolation in N dimensions.
|
136 |
+
|
137 |
+
Parameters
|
138 |
+
----------
|
139 |
+
y : (npoints, ndims) array_like
|
140 |
+
2-D array of data point coordinates.
|
141 |
+
d : (npoints, ...) array_like
|
142 |
+
N-D array of data values at `y`. The length of `d` along the first
|
143 |
+
axis must be equal to the length of `y`. Unlike some interpolators, the
|
144 |
+
interpolation axis cannot be changed.
|
145 |
+
neighbors : int, optional
|
146 |
+
If specified, the value of the interpolant at each evaluation point
|
147 |
+
will be computed using only this many nearest data points. All the data
|
148 |
+
points are used by default.
|
149 |
+
smoothing : float or (npoints, ) array_like, optional
|
150 |
+
Smoothing parameter. The interpolant perfectly fits the data when this
|
151 |
+
is set to 0. For large values, the interpolant approaches a least
|
152 |
+
squares fit of a polynomial with the specified degree. Default is 0.
|
153 |
+
kernel : str, optional
|
154 |
+
Type of RBF. This should be one of
|
155 |
+
|
156 |
+
- 'linear' : ``-r``
|
157 |
+
- 'thin_plate_spline' : ``r**2 * log(r)``
|
158 |
+
- 'cubic' : ``r**3``
|
159 |
+
- 'quintic' : ``-r**5``
|
160 |
+
- 'multiquadric' : ``-sqrt(1 + r**2)``
|
161 |
+
- 'inverse_multiquadric' : ``1/sqrt(1 + r**2)``
|
162 |
+
- 'inverse_quadratic' : ``1/(1 + r**2)``
|
163 |
+
- 'gaussian' : ``exp(-r**2)``
|
164 |
+
|
165 |
+
Default is 'thin_plate_spline'.
|
166 |
+
epsilon : float, optional
|
167 |
+
Shape parameter that scales the input to the RBF. If `kernel` is
|
168 |
+
'linear', 'thin_plate_spline', 'cubic', or 'quintic', this defaults to
|
169 |
+
1 and can be ignored because it has the same effect as scaling the
|
170 |
+
smoothing parameter. Otherwise, this must be specified.
|
171 |
+
degree : int, optional
|
172 |
+
Degree of the added polynomial. For some RBFs the interpolant may not
|
173 |
+
be well-posed if the polynomial degree is too small. Those RBFs and
|
174 |
+
their corresponding minimum degrees are
|
175 |
+
|
176 |
+
- 'multiquadric' : 0
|
177 |
+
- 'linear' : 0
|
178 |
+
- 'thin_plate_spline' : 1
|
179 |
+
- 'cubic' : 1
|
180 |
+
- 'quintic' : 2
|
181 |
+
|
182 |
+
The default value is the minimum degree for `kernel` or 0 if there is
|
183 |
+
no minimum degree. Set this to -1 for no added polynomial.
|
184 |
+
|
185 |
+
Notes
|
186 |
+
-----
|
187 |
+
An RBF is a scalar valued function in N-dimensional space whose value at
|
188 |
+
:math:`x` can be expressed in terms of :math:`r=||x - c||`, where :math:`c`
|
189 |
+
is the center of the RBF.
|
190 |
+
|
191 |
+
An RBF interpolant for the vector of data values :math:`d`, which are from
|
192 |
+
locations :math:`y`, is a linear combination of RBFs centered at :math:`y`
|
193 |
+
plus a polynomial with a specified degree. The RBF interpolant is written
|
194 |
+
as
|
195 |
+
|
196 |
+
.. math::
|
197 |
+
f(x) = K(x, y) a + P(x) b,
|
198 |
+
|
199 |
+
where :math:`K(x, y)` is a matrix of RBFs with centers at :math:`y`
|
200 |
+
evaluated at the points :math:`x`, and :math:`P(x)` is a matrix of
|
201 |
+
monomials, which span polynomials with the specified degree, evaluated at
|
202 |
+
:math:`x`. The coefficients :math:`a` and :math:`b` are the solution to the
|
203 |
+
linear equations
|
204 |
+
|
205 |
+
.. math::
|
206 |
+
(K(y, y) + \\lambda I) a + P(y) b = d
|
207 |
+
|
208 |
+
and
|
209 |
+
|
210 |
+
.. math::
|
211 |
+
P(y)^T a = 0,
|
212 |
+
|
213 |
+
where :math:`\\lambda` is a non-negative smoothing parameter that controls
|
214 |
+
how well we want to fit the data. The data are fit exactly when the
|
215 |
+
smoothing parameter is 0.
|
216 |
+
|
217 |
+
The above system is uniquely solvable if the following requirements are
|
218 |
+
met:
|
219 |
+
|
220 |
+
- :math:`P(y)` must have full column rank. :math:`P(y)` always has full
|
221 |
+
column rank when `degree` is -1 or 0. When `degree` is 1,
|
222 |
+
:math:`P(y)` has full column rank if the data point locations are not
|
223 |
+
all collinear (N=2), coplanar (N=3), etc.
|
224 |
+
- If `kernel` is 'multiquadric', 'linear', 'thin_plate_spline',
|
225 |
+
'cubic', or 'quintic', then `degree` must not be lower than the
|
226 |
+
minimum value listed above.
|
227 |
+
- If `smoothing` is 0, then each data point location must be distinct.
|
228 |
+
|
229 |
+
When using an RBF that is not scale invariant ('multiquadric',
|
230 |
+
'inverse_multiquadric', 'inverse_quadratic', or 'gaussian'), an appropriate
|
231 |
+
shape parameter must be chosen (e.g., through cross validation). Smaller
|
232 |
+
values for the shape parameter correspond to wider RBFs. The problem can
|
233 |
+
become ill-conditioned or singular when the shape parameter is too small.
|
234 |
+
|
235 |
+
The memory required to solve for the RBF interpolation coefficients
|
236 |
+
increases quadratically with the number of data points, which can become
|
237 |
+
impractical when interpolating more than about a thousand data points.
|
238 |
+
To overcome memory limitations for large interpolation problems, the
|
239 |
+
`neighbors` argument can be specified to compute an RBF interpolant for
|
240 |
+
each evaluation point using only the nearest data points.
|
241 |
+
|
242 |
+
.. versionadded:: 1.7.0
|
243 |
+
|
244 |
+
See Also
|
245 |
+
--------
|
246 |
+
NearestNDInterpolator
|
247 |
+
LinearNDInterpolator
|
248 |
+
CloughTocher2DInterpolator
|
249 |
+
|
250 |
+
References
|
251 |
+
----------
|
252 |
+
.. [1] Fasshauer, G., 2007. Meshfree Approximation Methods with Matlab.
|
253 |
+
World Scientific Publishing Co.
|
254 |
+
|
255 |
+
.. [2] http://amadeus.math.iit.edu/~fass/603_ch3.pdf
|
256 |
+
|
257 |
+
.. [3] Wahba, G., 1990. Spline Models for Observational Data. SIAM.
|
258 |
+
|
259 |
+
.. [4] http://pages.stat.wisc.edu/~wahba/stat860public/lect/lect8/lect8.pdf
|
260 |
+
|
261 |
+
Examples
|
262 |
+
--------
|
263 |
+
Demonstrate interpolating scattered data to a grid in 2-D.
|
264 |
+
|
265 |
+
>>> import numpy as np
|
266 |
+
>>> import matplotlib.pyplot as plt
|
267 |
+
>>> from scipy.interpolate import RBFInterpolator
|
268 |
+
>>> from scipy.stats.qmc import Halton
|
269 |
+
|
270 |
+
>>> rng = np.random.default_rng()
|
271 |
+
>>> xobs = 2*Halton(2, seed=rng).random(100) - 1
|
272 |
+
>>> yobs = np.sum(xobs, axis=1)*np.exp(-6*np.sum(xobs**2, axis=1))
|
273 |
+
|
274 |
+
>>> xgrid = np.mgrid[-1:1:50j, -1:1:50j]
|
275 |
+
>>> xflat = xgrid.reshape(2, -1).T
|
276 |
+
>>> yflat = RBFInterpolator(xobs, yobs)(xflat)
|
277 |
+
>>> ygrid = yflat.reshape(50, 50)
|
278 |
+
|
279 |
+
>>> fig, ax = plt.subplots()
|
280 |
+
>>> ax.pcolormesh(*xgrid, ygrid, vmin=-0.25, vmax=0.25, shading='gouraud')
|
281 |
+
>>> p = ax.scatter(*xobs.T, c=yobs, s=50, ec='k', vmin=-0.25, vmax=0.25)
|
282 |
+
>>> fig.colorbar(p)
|
283 |
+
>>> plt.show()
|
284 |
+
|
285 |
+
"""
|
286 |
+
|
287 |
+
def __init__(self, y, d,
|
288 |
+
neighbors=None,
|
289 |
+
smoothing=0.0,
|
290 |
+
kernel="thin_plate_spline",
|
291 |
+
epsilon=None,
|
292 |
+
degree=None):
|
293 |
+
y = np.asarray(y, dtype=float, order="C")
|
294 |
+
if y.ndim != 2:
|
295 |
+
raise ValueError("`y` must be a 2-dimensional array.")
|
296 |
+
|
297 |
+
ny, ndim = y.shape
|
298 |
+
|
299 |
+
d_dtype = complex if np.iscomplexobj(d) else float
|
300 |
+
d = np.asarray(d, dtype=d_dtype, order="C")
|
301 |
+
if d.shape[0] != ny:
|
302 |
+
raise ValueError(
|
303 |
+
f"Expected the first axis of `d` to have length {ny}."
|
304 |
+
)
|
305 |
+
|
306 |
+
d_shape = d.shape[1:]
|
307 |
+
d = d.reshape((ny, -1))
|
308 |
+
# If `d` is complex, convert it to a float array with twice as many
|
309 |
+
# columns. Otherwise, the LHS matrix would need to be converted to
|
310 |
+
# complex and take up 2x more memory than necessary.
|
311 |
+
d = d.view(float)
|
312 |
+
|
313 |
+
if np.isscalar(smoothing):
|
314 |
+
smoothing = np.full(ny, smoothing, dtype=float)
|
315 |
+
else:
|
316 |
+
smoothing = np.asarray(smoothing, dtype=float, order="C")
|
317 |
+
if smoothing.shape != (ny,):
|
318 |
+
raise ValueError(
|
319 |
+
"Expected `smoothing` to be a scalar or have shape "
|
320 |
+
f"({ny},)."
|
321 |
+
)
|
322 |
+
|
323 |
+
kernel = kernel.lower()
|
324 |
+
if kernel not in _AVAILABLE:
|
325 |
+
raise ValueError(f"`kernel` must be one of {_AVAILABLE}.")
|
326 |
+
|
327 |
+
if epsilon is None:
|
328 |
+
if kernel in _SCALE_INVARIANT:
|
329 |
+
epsilon = 1.0
|
330 |
+
else:
|
331 |
+
raise ValueError(
|
332 |
+
"`epsilon` must be specified if `kernel` is not one of "
|
333 |
+
f"{_SCALE_INVARIANT}."
|
334 |
+
)
|
335 |
+
else:
|
336 |
+
epsilon = float(epsilon)
|
337 |
+
|
338 |
+
min_degree = _NAME_TO_MIN_DEGREE.get(kernel, -1)
|
339 |
+
if degree is None:
|
340 |
+
degree = max(min_degree, 0)
|
341 |
+
else:
|
342 |
+
degree = int(degree)
|
343 |
+
if degree < -1:
|
344 |
+
raise ValueError("`degree` must be at least -1.")
|
345 |
+
elif -1 < degree < min_degree:
|
346 |
+
warnings.warn(
|
347 |
+
f"`degree` should not be below {min_degree} except -1 "
|
348 |
+
f"when `kernel` is '{kernel}'."
|
349 |
+
f"The interpolant may not be uniquely "
|
350 |
+
f"solvable, and the smoothing parameter may have an "
|
351 |
+
f"unintuitive effect.",
|
352 |
+
UserWarning, stacklevel=2
|
353 |
+
)
|
354 |
+
|
355 |
+
if neighbors is None:
|
356 |
+
nobs = ny
|
357 |
+
else:
|
358 |
+
# Make sure the number of nearest neighbors used for interpolation
|
359 |
+
# does not exceed the number of observations.
|
360 |
+
neighbors = int(min(neighbors, ny))
|
361 |
+
nobs = neighbors
|
362 |
+
|
363 |
+
powers = _monomial_powers(ndim, degree)
|
364 |
+
# The polynomial matrix must have full column rank in order for the
|
365 |
+
# interpolant to be well-posed, which is not possible if there are
|
366 |
+
# fewer observations than monomials.
|
367 |
+
if powers.shape[0] > nobs:
|
368 |
+
raise ValueError(
|
369 |
+
f"At least {powers.shape[0]} data points are required when "
|
370 |
+
f"`degree` is {degree} and the number of dimensions is {ndim}."
|
371 |
+
)
|
372 |
+
|
373 |
+
if neighbors is None:
|
374 |
+
shift, scale, coeffs = _build_and_solve_system(
|
375 |
+
y, d, smoothing, kernel, epsilon, powers
|
376 |
+
)
|
377 |
+
|
378 |
+
# Make these attributes private since they do not always exist.
|
379 |
+
self._shift = shift
|
380 |
+
self._scale = scale
|
381 |
+
self._coeffs = coeffs
|
382 |
+
|
383 |
+
else:
|
384 |
+
self._tree = KDTree(y)
|
385 |
+
|
386 |
+
self.y = y
|
387 |
+
self.d = d
|
388 |
+
self.d_shape = d_shape
|
389 |
+
self.d_dtype = d_dtype
|
390 |
+
self.neighbors = neighbors
|
391 |
+
self.smoothing = smoothing
|
392 |
+
self.kernel = kernel
|
393 |
+
self.epsilon = epsilon
|
394 |
+
self.powers = powers
|
395 |
+
|
396 |
+
def _chunk_evaluator(
|
397 |
+
self,
|
398 |
+
x,
|
399 |
+
y,
|
400 |
+
shift,
|
401 |
+
scale,
|
402 |
+
coeffs,
|
403 |
+
memory_budget=1000000
|
404 |
+
):
|
405 |
+
"""
|
406 |
+
Evaluate the interpolation while controlling memory consumption.
|
407 |
+
We chunk the input if we need more memory than specified.
|
408 |
+
|
409 |
+
Parameters
|
410 |
+
----------
|
411 |
+
x : (Q, N) float ndarray
|
412 |
+
array of points on which to evaluate
|
413 |
+
y: (P, N) float ndarray
|
414 |
+
array of points on which we know function values
|
415 |
+
shift: (N, ) ndarray
|
416 |
+
Domain shift used to create the polynomial matrix.
|
417 |
+
scale : (N,) float ndarray
|
418 |
+
Domain scaling used to create the polynomial matrix.
|
419 |
+
coeffs: (P+R, S) float ndarray
|
420 |
+
Coefficients in front of basis functions
|
421 |
+
memory_budget: int
|
422 |
+
Total amount of memory (in units of sizeof(float)) we wish
|
423 |
+
to devote for storing the array of coefficients for
|
424 |
+
interpolated points. If we need more memory than that, we
|
425 |
+
chunk the input.
|
426 |
+
|
427 |
+
Returns
|
428 |
+
-------
|
429 |
+
(Q, S) float ndarray
|
430 |
+
Interpolated array
|
431 |
+
"""
|
432 |
+
nx, ndim = x.shape
|
433 |
+
if self.neighbors is None:
|
434 |
+
nnei = len(y)
|
435 |
+
else:
|
436 |
+
nnei = self.neighbors
|
437 |
+
# in each chunk we consume the same space we already occupy
|
438 |
+
chunksize = memory_budget // (self.powers.shape[0] + nnei) + 1
|
439 |
+
if chunksize <= nx:
|
440 |
+
out = np.empty((nx, self.d.shape[1]), dtype=float)
|
441 |
+
for i in range(0, nx, chunksize):
|
442 |
+
vec = _build_evaluation_coefficients(
|
443 |
+
x[i:i + chunksize, :],
|
444 |
+
y,
|
445 |
+
self.kernel,
|
446 |
+
self.epsilon,
|
447 |
+
self.powers,
|
448 |
+
shift,
|
449 |
+
scale)
|
450 |
+
out[i:i + chunksize, :] = np.dot(vec, coeffs)
|
451 |
+
else:
|
452 |
+
vec = _build_evaluation_coefficients(
|
453 |
+
x,
|
454 |
+
y,
|
455 |
+
self.kernel,
|
456 |
+
self.epsilon,
|
457 |
+
self.powers,
|
458 |
+
shift,
|
459 |
+
scale)
|
460 |
+
out = np.dot(vec, coeffs)
|
461 |
+
return out
|
462 |
+
|
463 |
+
def __call__(self, x):
|
464 |
+
"""Evaluate the interpolant at `x`.
|
465 |
+
|
466 |
+
Parameters
|
467 |
+
----------
|
468 |
+
x : (Q, N) array_like
|
469 |
+
Evaluation point coordinates.
|
470 |
+
|
471 |
+
Returns
|
472 |
+
-------
|
473 |
+
(Q, ...) ndarray
|
474 |
+
Values of the interpolant at `x`.
|
475 |
+
|
476 |
+
"""
|
477 |
+
x = np.asarray(x, dtype=float, order="C")
|
478 |
+
if x.ndim != 2:
|
479 |
+
raise ValueError("`x` must be a 2-dimensional array.")
|
480 |
+
|
481 |
+
nx, ndim = x.shape
|
482 |
+
if ndim != self.y.shape[1]:
|
483 |
+
raise ValueError("Expected the second axis of `x` to have length "
|
484 |
+
f"{self.y.shape[1]}.")
|
485 |
+
|
486 |
+
# Our memory budget for storing RBF coefficients is
|
487 |
+
# based on how many floats in memory we already occupy
|
488 |
+
# If this number is below 1e6 we just use 1e6
|
489 |
+
# This memory budget is used to decide how we chunk
|
490 |
+
# the inputs
|
491 |
+
memory_budget = max(x.size + self.y.size + self.d.size, 1000000)
|
492 |
+
|
493 |
+
if self.neighbors is None:
|
494 |
+
out = self._chunk_evaluator(
|
495 |
+
x,
|
496 |
+
self.y,
|
497 |
+
self._shift,
|
498 |
+
self._scale,
|
499 |
+
self._coeffs,
|
500 |
+
memory_budget=memory_budget)
|
501 |
+
else:
|
502 |
+
# Get the indices of the k nearest observation points to each
|
503 |
+
# evaluation point.
|
504 |
+
_, yindices = self._tree.query(x, self.neighbors)
|
505 |
+
if self.neighbors == 1:
|
506 |
+
# `KDTree` squeezes the output when neighbors=1.
|
507 |
+
yindices = yindices[:, None]
|
508 |
+
|
509 |
+
# Multiple evaluation points may have the same neighborhood of
|
510 |
+
# observation points. Make the neighborhoods unique so that we only
|
511 |
+
# compute the interpolation coefficients once for each
|
512 |
+
# neighborhood.
|
513 |
+
yindices = np.sort(yindices, axis=1)
|
514 |
+
yindices, inv = np.unique(yindices, return_inverse=True, axis=0)
|
515 |
+
inv = np.reshape(inv, (-1,)) # flatten, we need 1-D indices
|
516 |
+
# `inv` tells us which neighborhood will be used by each evaluation
|
517 |
+
# point. Now we find which evaluation points will be using each
|
518 |
+
# neighborhood.
|
519 |
+
xindices = [[] for _ in range(len(yindices))]
|
520 |
+
for i, j in enumerate(inv):
|
521 |
+
xindices[j].append(i)
|
522 |
+
|
523 |
+
out = np.empty((nx, self.d.shape[1]), dtype=float)
|
524 |
+
for xidx, yidx in zip(xindices, yindices):
|
525 |
+
# `yidx` are the indices of the observations in this
|
526 |
+
# neighborhood. `xidx` are the indices of the evaluation points
|
527 |
+
# that are using this neighborhood.
|
528 |
+
xnbr = x[xidx]
|
529 |
+
ynbr = self.y[yidx]
|
530 |
+
dnbr = self.d[yidx]
|
531 |
+
snbr = self.smoothing[yidx]
|
532 |
+
shift, scale, coeffs = _build_and_solve_system(
|
533 |
+
ynbr,
|
534 |
+
dnbr,
|
535 |
+
snbr,
|
536 |
+
self.kernel,
|
537 |
+
self.epsilon,
|
538 |
+
self.powers,
|
539 |
+
)
|
540 |
+
out[xidx] = self._chunk_evaluator(
|
541 |
+
xnbr,
|
542 |
+
ynbr,
|
543 |
+
shift,
|
544 |
+
scale,
|
545 |
+
coeffs,
|
546 |
+
memory_budget=memory_budget)
|
547 |
+
|
548 |
+
out = out.view(self.d_dtype)
|
549 |
+
out = out.reshape((nx, ) + self.d_shape)
|
550 |
+
return out
|
env-llmeval/lib/python3.10/site-packages/scipy/interpolate/_rgi.py
ADDED
@@ -0,0 +1,766 @@
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|
1 |
+
__all__ = ['RegularGridInterpolator', 'interpn']
|
2 |
+
|
3 |
+
import itertools
|
4 |
+
import warnings
|
5 |
+
|
6 |
+
import numpy as np
|
7 |
+
|
8 |
+
import scipy.sparse.linalg as ssl
|
9 |
+
|
10 |
+
from .interpnd import _ndim_coords_from_arrays
|
11 |
+
from ._cubic import PchipInterpolator
|
12 |
+
from ._rgi_cython import evaluate_linear_2d, find_indices
|
13 |
+
from ._bsplines import make_interp_spline
|
14 |
+
from ._fitpack2 import RectBivariateSpline
|
15 |
+
from ._ndbspline import make_ndbspl
|
16 |
+
|
17 |
+
|
18 |
+
def _check_points(points):
|
19 |
+
descending_dimensions = []
|
20 |
+
grid = []
|
21 |
+
for i, p in enumerate(points):
|
22 |
+
# early make points float
|
23 |
+
# see https://github.com/scipy/scipy/pull/17230
|
24 |
+
p = np.asarray(p, dtype=float)
|
25 |
+
if not np.all(p[1:] > p[:-1]):
|
26 |
+
if np.all(p[1:] < p[:-1]):
|
27 |
+
# input is descending, so make it ascending
|
28 |
+
descending_dimensions.append(i)
|
29 |
+
p = np.flip(p)
|
30 |
+
else:
|
31 |
+
raise ValueError(
|
32 |
+
"The points in dimension %d must be strictly "
|
33 |
+
"ascending or descending" % i)
|
34 |
+
# see https://github.com/scipy/scipy/issues/17716
|
35 |
+
p = np.ascontiguousarray(p)
|
36 |
+
grid.append(p)
|
37 |
+
return tuple(grid), tuple(descending_dimensions)
|
38 |
+
|
39 |
+
|
40 |
+
def _check_dimensionality(points, values):
|
41 |
+
if len(points) > values.ndim:
|
42 |
+
raise ValueError("There are %d point arrays, but values has %d "
|
43 |
+
"dimensions" % (len(points), values.ndim))
|
44 |
+
for i, p in enumerate(points):
|
45 |
+
if not np.asarray(p).ndim == 1:
|
46 |
+
raise ValueError("The points in dimension %d must be "
|
47 |
+
"1-dimensional" % i)
|
48 |
+
if not values.shape[i] == len(p):
|
49 |
+
raise ValueError("There are %d points and %d values in "
|
50 |
+
"dimension %d" % (len(p), values.shape[i], i))
|
51 |
+
|
52 |
+
|
53 |
+
class RegularGridInterpolator:
|
54 |
+
"""
|
55 |
+
Interpolator on a regular or rectilinear grid in arbitrary dimensions.
|
56 |
+
|
57 |
+
The data must be defined on a rectilinear grid; that is, a rectangular
|
58 |
+
grid with even or uneven spacing. Linear, nearest-neighbor, spline
|
59 |
+
interpolations are supported. After setting up the interpolator object,
|
60 |
+
the interpolation method may be chosen at each evaluation.
|
61 |
+
|
62 |
+
Parameters
|
63 |
+
----------
|
64 |
+
points : tuple of ndarray of float, with shapes (m1, ), ..., (mn, )
|
65 |
+
The points defining the regular grid in n dimensions. The points in
|
66 |
+
each dimension (i.e. every elements of the points tuple) must be
|
67 |
+
strictly ascending or descending.
|
68 |
+
|
69 |
+
values : array_like, shape (m1, ..., mn, ...)
|
70 |
+
The data on the regular grid in n dimensions. Complex data is
|
71 |
+
accepted.
|
72 |
+
|
73 |
+
.. deprecated:: 1.13.0
|
74 |
+
Complex data is deprecated with ``method="pchip"`` and will raise an
|
75 |
+
error in SciPy 1.15.0. This is because ``PchipInterpolator`` only
|
76 |
+
works with real values. If you are trying to use the real components of
|
77 |
+
the passed array, use ``np.real`` on ``values``.
|
78 |
+
|
79 |
+
method : str, optional
|
80 |
+
The method of interpolation to perform. Supported are "linear",
|
81 |
+
"nearest", "slinear", "cubic", "quintic" and "pchip". This
|
82 |
+
parameter will become the default for the object's ``__call__``
|
83 |
+
method. Default is "linear".
|
84 |
+
|
85 |
+
bounds_error : bool, optional
|
86 |
+
If True, when interpolated values are requested outside of the
|
87 |
+
domain of the input data, a ValueError is raised.
|
88 |
+
If False, then `fill_value` is used.
|
89 |
+
Default is True.
|
90 |
+
|
91 |
+
fill_value : float or None, optional
|
92 |
+
The value to use for points outside of the interpolation domain.
|
93 |
+
If None, values outside the domain are extrapolated.
|
94 |
+
Default is ``np.nan``.
|
95 |
+
|
96 |
+
solver : callable, optional
|
97 |
+
Only used for methods "slinear", "cubic" and "quintic".
|
98 |
+
Sparse linear algebra solver for construction of the NdBSpline instance.
|
99 |
+
Default is the iterative solver `scipy.sparse.linalg.gcrotmk`.
|
100 |
+
|
101 |
+
.. versionadded:: 1.13
|
102 |
+
|
103 |
+
solver_args: dict, optional
|
104 |
+
Additional arguments to pass to `solver`, if any.
|
105 |
+
|
106 |
+
.. versionadded:: 1.13
|
107 |
+
|
108 |
+
Methods
|
109 |
+
-------
|
110 |
+
__call__
|
111 |
+
|
112 |
+
Attributes
|
113 |
+
----------
|
114 |
+
grid : tuple of ndarrays
|
115 |
+
The points defining the regular grid in n dimensions.
|
116 |
+
This tuple defines the full grid via
|
117 |
+
``np.meshgrid(*grid, indexing='ij')``
|
118 |
+
values : ndarray
|
119 |
+
Data values at the grid.
|
120 |
+
method : str
|
121 |
+
Interpolation method.
|
122 |
+
fill_value : float or ``None``
|
123 |
+
Use this value for out-of-bounds arguments to `__call__`.
|
124 |
+
bounds_error : bool
|
125 |
+
If ``True``, out-of-bounds argument raise a ``ValueError``.
|
126 |
+
|
127 |
+
Notes
|
128 |
+
-----
|
129 |
+
Contrary to `LinearNDInterpolator` and `NearestNDInterpolator`, this class
|
130 |
+
avoids expensive triangulation of the input data by taking advantage of the
|
131 |
+
regular grid structure.
|
132 |
+
|
133 |
+
In other words, this class assumes that the data is defined on a
|
134 |
+
*rectilinear* grid.
|
135 |
+
|
136 |
+
.. versionadded:: 0.14
|
137 |
+
|
138 |
+
The 'slinear'(k=1), 'cubic'(k=3), and 'quintic'(k=5) methods are
|
139 |
+
tensor-product spline interpolators, where `k` is the spline degree,
|
140 |
+
If any dimension has fewer points than `k` + 1, an error will be raised.
|
141 |
+
|
142 |
+
.. versionadded:: 1.9
|
143 |
+
|
144 |
+
If the input data is such that dimensions have incommensurate
|
145 |
+
units and differ by many orders of magnitude, the interpolant may have
|
146 |
+
numerical artifacts. Consider rescaling the data before interpolating.
|
147 |
+
|
148 |
+
**Choosing a solver for spline methods**
|
149 |
+
|
150 |
+
Spline methods, "slinear", "cubic" and "quintic" involve solving a
|
151 |
+
large sparse linear system at instantiation time. Depending on data,
|
152 |
+
the default solver may or may not be adequate. When it is not, you may
|
153 |
+
need to experiment with an optional `solver` argument, where you may
|
154 |
+
choose between the direct solver (`scipy.sparse.linalg.spsolve`) or
|
155 |
+
iterative solvers from `scipy.sparse.linalg`. You may need to supply
|
156 |
+
additional parameters via the optional `solver_args` parameter (for instance,
|
157 |
+
you may supply the starting value or target tolerance). See the
|
158 |
+
`scipy.sparse.linalg` documentation for the full list of available options.
|
159 |
+
|
160 |
+
Alternatively, you may instead use the legacy methods, "slinear_legacy",
|
161 |
+
"cubic_legacy" and "quintic_legacy". These methods allow faster construction
|
162 |
+
but evaluations will be much slower.
|
163 |
+
|
164 |
+
Examples
|
165 |
+
--------
|
166 |
+
**Evaluate a function on the points of a 3-D grid**
|
167 |
+
|
168 |
+
As a first example, we evaluate a simple example function on the points of
|
169 |
+
a 3-D grid:
|
170 |
+
|
171 |
+
>>> from scipy.interpolate import RegularGridInterpolator
|
172 |
+
>>> import numpy as np
|
173 |
+
>>> def f(x, y, z):
|
174 |
+
... return 2 * x**3 + 3 * y**2 - z
|
175 |
+
>>> x = np.linspace(1, 4, 11)
|
176 |
+
>>> y = np.linspace(4, 7, 22)
|
177 |
+
>>> z = np.linspace(7, 9, 33)
|
178 |
+
>>> xg, yg ,zg = np.meshgrid(x, y, z, indexing='ij', sparse=True)
|
179 |
+
>>> data = f(xg, yg, zg)
|
180 |
+
|
181 |
+
``data`` is now a 3-D array with ``data[i, j, k] = f(x[i], y[j], z[k])``.
|
182 |
+
Next, define an interpolating function from this data:
|
183 |
+
|
184 |
+
>>> interp = RegularGridInterpolator((x, y, z), data)
|
185 |
+
|
186 |
+
Evaluate the interpolating function at the two points
|
187 |
+
``(x,y,z) = (2.1, 6.2, 8.3)`` and ``(3.3, 5.2, 7.1)``:
|
188 |
+
|
189 |
+
>>> pts = np.array([[2.1, 6.2, 8.3],
|
190 |
+
... [3.3, 5.2, 7.1]])
|
191 |
+
>>> interp(pts)
|
192 |
+
array([ 125.80469388, 146.30069388])
|
193 |
+
|
194 |
+
which is indeed a close approximation to
|
195 |
+
|
196 |
+
>>> f(2.1, 6.2, 8.3), f(3.3, 5.2, 7.1)
|
197 |
+
(125.54200000000002, 145.894)
|
198 |
+
|
199 |
+
**Interpolate and extrapolate a 2D dataset**
|
200 |
+
|
201 |
+
As a second example, we interpolate and extrapolate a 2D data set:
|
202 |
+
|
203 |
+
>>> x, y = np.array([-2, 0, 4]), np.array([-2, 0, 2, 5])
|
204 |
+
>>> def ff(x, y):
|
205 |
+
... return x**2 + y**2
|
206 |
+
|
207 |
+
>>> xg, yg = np.meshgrid(x, y, indexing='ij')
|
208 |
+
>>> data = ff(xg, yg)
|
209 |
+
>>> interp = RegularGridInterpolator((x, y), data,
|
210 |
+
... bounds_error=False, fill_value=None)
|
211 |
+
|
212 |
+
>>> import matplotlib.pyplot as plt
|
213 |
+
>>> fig = plt.figure()
|
214 |
+
>>> ax = fig.add_subplot(projection='3d')
|
215 |
+
>>> ax.scatter(xg.ravel(), yg.ravel(), data.ravel(),
|
216 |
+
... s=60, c='k', label='data')
|
217 |
+
|
218 |
+
Evaluate and plot the interpolator on a finer grid
|
219 |
+
|
220 |
+
>>> xx = np.linspace(-4, 9, 31)
|
221 |
+
>>> yy = np.linspace(-4, 9, 31)
|
222 |
+
>>> X, Y = np.meshgrid(xx, yy, indexing='ij')
|
223 |
+
|
224 |
+
>>> # interpolator
|
225 |
+
>>> ax.plot_wireframe(X, Y, interp((X, Y)), rstride=3, cstride=3,
|
226 |
+
... alpha=0.4, color='m', label='linear interp')
|
227 |
+
|
228 |
+
>>> # ground truth
|
229 |
+
>>> ax.plot_wireframe(X, Y, ff(X, Y), rstride=3, cstride=3,
|
230 |
+
... alpha=0.4, label='ground truth')
|
231 |
+
>>> plt.legend()
|
232 |
+
>>> plt.show()
|
233 |
+
|
234 |
+
Other examples are given
|
235 |
+
:ref:`in the tutorial <tutorial-interpolate_regular_grid_interpolator>`.
|
236 |
+
|
237 |
+
See Also
|
238 |
+
--------
|
239 |
+
NearestNDInterpolator : Nearest neighbor interpolator on *unstructured*
|
240 |
+
data in N dimensions
|
241 |
+
|
242 |
+
LinearNDInterpolator : Piecewise linear interpolator on *unstructured* data
|
243 |
+
in N dimensions
|
244 |
+
|
245 |
+
interpn : a convenience function which wraps `RegularGridInterpolator`
|
246 |
+
|
247 |
+
scipy.ndimage.map_coordinates : interpolation on grids with equal spacing
|
248 |
+
(suitable for e.g., N-D image resampling)
|
249 |
+
|
250 |
+
References
|
251 |
+
----------
|
252 |
+
.. [1] Python package *regulargrid* by Johannes Buchner, see
|
253 |
+
https://pypi.python.org/pypi/regulargrid/
|
254 |
+
.. [2] Wikipedia, "Trilinear interpolation",
|
255 |
+
https://en.wikipedia.org/wiki/Trilinear_interpolation
|
256 |
+
.. [3] Weiser, Alan, and Sergio E. Zarantonello. "A note on piecewise linear
|
257 |
+
and multilinear table interpolation in many dimensions." MATH.
|
258 |
+
COMPUT. 50.181 (1988): 189-196.
|
259 |
+
https://www.ams.org/journals/mcom/1988-50-181/S0025-5718-1988-0917826-0/S0025-5718-1988-0917826-0.pdf
|
260 |
+
:doi:`10.1090/S0025-5718-1988-0917826-0`
|
261 |
+
|
262 |
+
"""
|
263 |
+
# this class is based on code originally programmed by Johannes Buchner,
|
264 |
+
# see https://github.com/JohannesBuchner/regulargrid
|
265 |
+
|
266 |
+
_SPLINE_DEGREE_MAP = {"slinear": 1, "cubic": 3, "quintic": 5, 'pchip': 3,
|
267 |
+
"slinear_legacy": 1, "cubic_legacy": 3, "quintic_legacy": 5,}
|
268 |
+
_SPLINE_METHODS_recursive = {"slinear_legacy", "cubic_legacy",
|
269 |
+
"quintic_legacy", "pchip"}
|
270 |
+
_SPLINE_METHODS_ndbspl = {"slinear", "cubic", "quintic"}
|
271 |
+
_SPLINE_METHODS = list(_SPLINE_DEGREE_MAP.keys())
|
272 |
+
_ALL_METHODS = ["linear", "nearest"] + _SPLINE_METHODS
|
273 |
+
|
274 |
+
def __init__(self, points, values, method="linear", bounds_error=True,
|
275 |
+
fill_value=np.nan, *, solver=None, solver_args=None):
|
276 |
+
if method not in self._ALL_METHODS:
|
277 |
+
raise ValueError("Method '%s' is not defined" % method)
|
278 |
+
elif method in self._SPLINE_METHODS:
|
279 |
+
self._validate_grid_dimensions(points, method)
|
280 |
+
self.method = method
|
281 |
+
self.bounds_error = bounds_error
|
282 |
+
self.grid, self._descending_dimensions = _check_points(points)
|
283 |
+
self.values = self._check_values(values)
|
284 |
+
self._check_dimensionality(self.grid, self.values)
|
285 |
+
self.fill_value = self._check_fill_value(self.values, fill_value)
|
286 |
+
if self._descending_dimensions:
|
287 |
+
self.values = np.flip(values, axis=self._descending_dimensions)
|
288 |
+
if self.method == "pchip" and np.iscomplexobj(self.values):
|
289 |
+
msg = ("`PchipInterpolator` only works with real values. Passing "
|
290 |
+
"complex-dtyped `values` with `method='pchip'` is deprecated "
|
291 |
+
"and will raise an error in SciPy 1.15.0. If you are trying to "
|
292 |
+
"use the real components of the passed array, use `np.real` on "
|
293 |
+
"the array before passing to `RegularGridInterpolator`.")
|
294 |
+
warnings.warn(msg, DeprecationWarning, stacklevel=2)
|
295 |
+
if method in self._SPLINE_METHODS_ndbspl:
|
296 |
+
if solver_args is None:
|
297 |
+
solver_args = {}
|
298 |
+
self._spline = self._construct_spline(method, solver, **solver_args)
|
299 |
+
else:
|
300 |
+
if solver is not None or solver_args:
|
301 |
+
raise ValueError(
|
302 |
+
f"{method =} does not accept the 'solver' argument. Got "
|
303 |
+
f" {solver = } and with arguments {solver_args}."
|
304 |
+
)
|
305 |
+
|
306 |
+
def _construct_spline(self, method, solver=None, **solver_args):
|
307 |
+
if solver is None:
|
308 |
+
solver = ssl.gcrotmk
|
309 |
+
spl = make_ndbspl(
|
310 |
+
self.grid, self.values, self._SPLINE_DEGREE_MAP[method],
|
311 |
+
solver=solver, **solver_args
|
312 |
+
)
|
313 |
+
return spl
|
314 |
+
|
315 |
+
def _check_dimensionality(self, grid, values):
|
316 |
+
_check_dimensionality(grid, values)
|
317 |
+
|
318 |
+
def _check_points(self, points):
|
319 |
+
return _check_points(points)
|
320 |
+
|
321 |
+
def _check_values(self, values):
|
322 |
+
if not hasattr(values, 'ndim'):
|
323 |
+
# allow reasonable duck-typed values
|
324 |
+
values = np.asarray(values)
|
325 |
+
|
326 |
+
if hasattr(values, 'dtype') and hasattr(values, 'astype'):
|
327 |
+
if not np.issubdtype(values.dtype, np.inexact):
|
328 |
+
values = values.astype(float)
|
329 |
+
|
330 |
+
return values
|
331 |
+
|
332 |
+
def _check_fill_value(self, values, fill_value):
|
333 |
+
if fill_value is not None:
|
334 |
+
fill_value_dtype = np.asarray(fill_value).dtype
|
335 |
+
if (hasattr(values, 'dtype') and not
|
336 |
+
np.can_cast(fill_value_dtype, values.dtype,
|
337 |
+
casting='same_kind')):
|
338 |
+
raise ValueError("fill_value must be either 'None' or "
|
339 |
+
"of a type compatible with values")
|
340 |
+
return fill_value
|
341 |
+
|
342 |
+
def __call__(self, xi, method=None, *, nu=None):
|
343 |
+
"""
|
344 |
+
Interpolation at coordinates.
|
345 |
+
|
346 |
+
Parameters
|
347 |
+
----------
|
348 |
+
xi : ndarray of shape (..., ndim)
|
349 |
+
The coordinates to evaluate the interpolator at.
|
350 |
+
|
351 |
+
method : str, optional
|
352 |
+
The method of interpolation to perform. Supported are "linear",
|
353 |
+
"nearest", "slinear", "cubic", "quintic" and "pchip". Default is
|
354 |
+
the method chosen when the interpolator was created.
|
355 |
+
|
356 |
+
nu : sequence of ints, length ndim, optional
|
357 |
+
If not None, the orders of the derivatives to evaluate.
|
358 |
+
Each entry must be non-negative.
|
359 |
+
Only allowed for methods "slinear", "cubic" and "quintic".
|
360 |
+
|
361 |
+
.. versionadded:: 1.13
|
362 |
+
|
363 |
+
Returns
|
364 |
+
-------
|
365 |
+
values_x : ndarray, shape xi.shape[:-1] + values.shape[ndim:]
|
366 |
+
Interpolated values at `xi`. See notes for behaviour when
|
367 |
+
``xi.ndim == 1``.
|
368 |
+
|
369 |
+
Notes
|
370 |
+
-----
|
371 |
+
In the case that ``xi.ndim == 1`` a new axis is inserted into
|
372 |
+
the 0 position of the returned array, values_x, so its shape is
|
373 |
+
instead ``(1,) + values.shape[ndim:]``.
|
374 |
+
|
375 |
+
Examples
|
376 |
+
--------
|
377 |
+
Here we define a nearest-neighbor interpolator of a simple function
|
378 |
+
|
379 |
+
>>> import numpy as np
|
380 |
+
>>> x, y = np.array([0, 1, 2]), np.array([1, 3, 7])
|
381 |
+
>>> def f(x, y):
|
382 |
+
... return x**2 + y**2
|
383 |
+
>>> data = f(*np.meshgrid(x, y, indexing='ij', sparse=True))
|
384 |
+
>>> from scipy.interpolate import RegularGridInterpolator
|
385 |
+
>>> interp = RegularGridInterpolator((x, y), data, method='nearest')
|
386 |
+
|
387 |
+
By construction, the interpolator uses the nearest-neighbor
|
388 |
+
interpolation
|
389 |
+
|
390 |
+
>>> interp([[1.5, 1.3], [0.3, 4.5]])
|
391 |
+
array([2., 9.])
|
392 |
+
|
393 |
+
We can however evaluate the linear interpolant by overriding the
|
394 |
+
`method` parameter
|
395 |
+
|
396 |
+
>>> interp([[1.5, 1.3], [0.3, 4.5]], method='linear')
|
397 |
+
array([ 4.7, 24.3])
|
398 |
+
"""
|
399 |
+
method = self.method if method is None else method
|
400 |
+
is_method_changed = self.method != method
|
401 |
+
if method not in self._ALL_METHODS:
|
402 |
+
raise ValueError("Method '%s' is not defined" % method)
|
403 |
+
if is_method_changed and method in self._SPLINE_METHODS_ndbspl:
|
404 |
+
self._spline = self._construct_spline(method)
|
405 |
+
|
406 |
+
if nu is not None and method not in self._SPLINE_METHODS_ndbspl:
|
407 |
+
raise ValueError(
|
408 |
+
f"Can only compute derivatives for methods "
|
409 |
+
f"{self._SPLINE_METHODS_ndbspl}, got {method =}."
|
410 |
+
)
|
411 |
+
|
412 |
+
xi, xi_shape, ndim, nans, out_of_bounds = self._prepare_xi(xi)
|
413 |
+
|
414 |
+
if method == "linear":
|
415 |
+
indices, norm_distances = self._find_indices(xi.T)
|
416 |
+
if (ndim == 2 and hasattr(self.values, 'dtype') and
|
417 |
+
self.values.ndim == 2 and self.values.flags.writeable and
|
418 |
+
self.values.dtype in (np.float64, np.complex128) and
|
419 |
+
self.values.dtype.byteorder == '='):
|
420 |
+
# until cython supports const fused types, the fast path
|
421 |
+
# cannot support non-writeable values
|
422 |
+
# a fast path
|
423 |
+
out = np.empty(indices.shape[1], dtype=self.values.dtype)
|
424 |
+
result = evaluate_linear_2d(self.values,
|
425 |
+
indices,
|
426 |
+
norm_distances,
|
427 |
+
self.grid,
|
428 |
+
out)
|
429 |
+
else:
|
430 |
+
result = self._evaluate_linear(indices, norm_distances)
|
431 |
+
elif method == "nearest":
|
432 |
+
indices, norm_distances = self._find_indices(xi.T)
|
433 |
+
result = self._evaluate_nearest(indices, norm_distances)
|
434 |
+
elif method in self._SPLINE_METHODS:
|
435 |
+
if is_method_changed:
|
436 |
+
self._validate_grid_dimensions(self.grid, method)
|
437 |
+
if method in self._SPLINE_METHODS_recursive:
|
438 |
+
result = self._evaluate_spline(xi, method)
|
439 |
+
else:
|
440 |
+
result = self._spline(xi, nu=nu)
|
441 |
+
|
442 |
+
if not self.bounds_error and self.fill_value is not None:
|
443 |
+
result[out_of_bounds] = self.fill_value
|
444 |
+
|
445 |
+
# f(nan) = nan, if any
|
446 |
+
if np.any(nans):
|
447 |
+
result[nans] = np.nan
|
448 |
+
return result.reshape(xi_shape[:-1] + self.values.shape[ndim:])
|
449 |
+
|
450 |
+
def _prepare_xi(self, xi):
|
451 |
+
ndim = len(self.grid)
|
452 |
+
xi = _ndim_coords_from_arrays(xi, ndim=ndim)
|
453 |
+
if xi.shape[-1] != len(self.grid):
|
454 |
+
raise ValueError("The requested sample points xi have dimension "
|
455 |
+
f"{xi.shape[-1]} but this "
|
456 |
+
f"RegularGridInterpolator has dimension {ndim}")
|
457 |
+
|
458 |
+
xi_shape = xi.shape
|
459 |
+
xi = xi.reshape(-1, xi_shape[-1])
|
460 |
+
xi = np.asarray(xi, dtype=float)
|
461 |
+
|
462 |
+
# find nans in input
|
463 |
+
nans = np.any(np.isnan(xi), axis=-1)
|
464 |
+
|
465 |
+
if self.bounds_error:
|
466 |
+
for i, p in enumerate(xi.T):
|
467 |
+
if not np.logical_and(np.all(self.grid[i][0] <= p),
|
468 |
+
np.all(p <= self.grid[i][-1])):
|
469 |
+
raise ValueError("One of the requested xi is out of bounds "
|
470 |
+
"in dimension %d" % i)
|
471 |
+
out_of_bounds = None
|
472 |
+
else:
|
473 |
+
out_of_bounds = self._find_out_of_bounds(xi.T)
|
474 |
+
|
475 |
+
return xi, xi_shape, ndim, nans, out_of_bounds
|
476 |
+
|
477 |
+
def _evaluate_linear(self, indices, norm_distances):
|
478 |
+
# slice for broadcasting over trailing dimensions in self.values
|
479 |
+
vslice = (slice(None),) + (None,)*(self.values.ndim - len(indices))
|
480 |
+
|
481 |
+
# Compute shifting up front before zipping everything together
|
482 |
+
shift_norm_distances = [1 - yi for yi in norm_distances]
|
483 |
+
shift_indices = [i + 1 for i in indices]
|
484 |
+
|
485 |
+
# The formula for linear interpolation in 2d takes the form:
|
486 |
+
# values = self.values[(i0, i1)] * (1 - y0) * (1 - y1) + \
|
487 |
+
# self.values[(i0, i1 + 1)] * (1 - y0) * y1 + \
|
488 |
+
# self.values[(i0 + 1, i1)] * y0 * (1 - y1) + \
|
489 |
+
# self.values[(i0 + 1, i1 + 1)] * y0 * y1
|
490 |
+
# We pair i with 1 - yi (zipped1) and i + 1 with yi (zipped2)
|
491 |
+
zipped1 = zip(indices, shift_norm_distances)
|
492 |
+
zipped2 = zip(shift_indices, norm_distances)
|
493 |
+
|
494 |
+
# Take all products of zipped1 and zipped2 and iterate over them
|
495 |
+
# to get the terms in the above formula. This corresponds to iterating
|
496 |
+
# over the vertices of a hypercube.
|
497 |
+
hypercube = itertools.product(*zip(zipped1, zipped2))
|
498 |
+
value = np.array([0.])
|
499 |
+
for h in hypercube:
|
500 |
+
edge_indices, weights = zip(*h)
|
501 |
+
weight = np.array([1.])
|
502 |
+
for w in weights:
|
503 |
+
weight = weight * w
|
504 |
+
term = np.asarray(self.values[edge_indices]) * weight[vslice]
|
505 |
+
value = value + term # cannot use += because broadcasting
|
506 |
+
return value
|
507 |
+
|
508 |
+
def _evaluate_nearest(self, indices, norm_distances):
|
509 |
+
idx_res = [np.where(yi <= .5, i, i + 1)
|
510 |
+
for i, yi in zip(indices, norm_distances)]
|
511 |
+
return self.values[tuple(idx_res)]
|
512 |
+
|
513 |
+
def _validate_grid_dimensions(self, points, method):
|
514 |
+
k = self._SPLINE_DEGREE_MAP[method]
|
515 |
+
for i, point in enumerate(points):
|
516 |
+
ndim = len(np.atleast_1d(point))
|
517 |
+
if ndim <= k:
|
518 |
+
raise ValueError(f"There are {ndim} points in dimension {i},"
|
519 |
+
f" but method {method} requires at least "
|
520 |
+
f" {k+1} points per dimension.")
|
521 |
+
|
522 |
+
def _evaluate_spline(self, xi, method):
|
523 |
+
# ensure xi is 2D list of points to evaluate (`m` is the number of
|
524 |
+
# points and `n` is the number of interpolation dimensions,
|
525 |
+
# ``n == len(self.grid)``.)
|
526 |
+
if xi.ndim == 1:
|
527 |
+
xi = xi.reshape((1, xi.size))
|
528 |
+
m, n = xi.shape
|
529 |
+
|
530 |
+
# Reorder the axes: n-dimensional process iterates over the
|
531 |
+
# interpolation axes from the last axis downwards: E.g. for a 4D grid
|
532 |
+
# the order of axes is 3, 2, 1, 0. Each 1D interpolation works along
|
533 |
+
# the 0th axis of its argument array (for 1D routine it's its ``y``
|
534 |
+
# array). Thus permute the interpolation axes of `values` *and keep
|
535 |
+
# trailing dimensions trailing*.
|
536 |
+
axes = tuple(range(self.values.ndim))
|
537 |
+
axx = axes[:n][::-1] + axes[n:]
|
538 |
+
values = self.values.transpose(axx)
|
539 |
+
|
540 |
+
if method == 'pchip':
|
541 |
+
_eval_func = self._do_pchip
|
542 |
+
else:
|
543 |
+
_eval_func = self._do_spline_fit
|
544 |
+
k = self._SPLINE_DEGREE_MAP[method]
|
545 |
+
|
546 |
+
# Non-stationary procedure: difficult to vectorize this part entirely
|
547 |
+
# into numpy-level operations. Unfortunately this requires explicit
|
548 |
+
# looping over each point in xi.
|
549 |
+
|
550 |
+
# can at least vectorize the first pass across all points in the
|
551 |
+
# last variable of xi.
|
552 |
+
last_dim = n - 1
|
553 |
+
first_values = _eval_func(self.grid[last_dim],
|
554 |
+
values,
|
555 |
+
xi[:, last_dim],
|
556 |
+
k)
|
557 |
+
|
558 |
+
# the rest of the dimensions have to be on a per point-in-xi basis
|
559 |
+
shape = (m, *self.values.shape[n:])
|
560 |
+
result = np.empty(shape, dtype=self.values.dtype)
|
561 |
+
for j in range(m):
|
562 |
+
# Main process: Apply 1D interpolate in each dimension
|
563 |
+
# sequentially, starting with the last dimension.
|
564 |
+
# These are then "folded" into the next dimension in-place.
|
565 |
+
folded_values = first_values[j, ...]
|
566 |
+
for i in range(last_dim-1, -1, -1):
|
567 |
+
# Interpolate for each 1D from the last dimensions.
|
568 |
+
# This collapses each 1D sequence into a scalar.
|
569 |
+
folded_values = _eval_func(self.grid[i],
|
570 |
+
folded_values,
|
571 |
+
xi[j, i],
|
572 |
+
k)
|
573 |
+
result[j, ...] = folded_values
|
574 |
+
|
575 |
+
return result
|
576 |
+
|
577 |
+
@staticmethod
|
578 |
+
def _do_spline_fit(x, y, pt, k):
|
579 |
+
local_interp = make_interp_spline(x, y, k=k, axis=0)
|
580 |
+
values = local_interp(pt)
|
581 |
+
return values
|
582 |
+
|
583 |
+
@staticmethod
|
584 |
+
def _do_pchip(x, y, pt, k):
|
585 |
+
local_interp = PchipInterpolator(x, y, axis=0)
|
586 |
+
values = local_interp(pt)
|
587 |
+
return values
|
588 |
+
|
589 |
+
def _find_indices(self, xi):
|
590 |
+
return find_indices(self.grid, xi)
|
591 |
+
|
592 |
+
def _find_out_of_bounds(self, xi):
|
593 |
+
# check for out of bounds xi
|
594 |
+
out_of_bounds = np.zeros((xi.shape[1]), dtype=bool)
|
595 |
+
# iterate through dimensions
|
596 |
+
for x, grid in zip(xi, self.grid):
|
597 |
+
out_of_bounds += x < grid[0]
|
598 |
+
out_of_bounds += x > grid[-1]
|
599 |
+
return out_of_bounds
|
600 |
+
|
601 |
+
|
602 |
+
def interpn(points, values, xi, method="linear", bounds_error=True,
|
603 |
+
fill_value=np.nan):
|
604 |
+
"""
|
605 |
+
Multidimensional interpolation on regular or rectilinear grids.
|
606 |
+
|
607 |
+
Strictly speaking, not all regular grids are supported - this function
|
608 |
+
works on *rectilinear* grids, that is, a rectangular grid with even or
|
609 |
+
uneven spacing.
|
610 |
+
|
611 |
+
Parameters
|
612 |
+
----------
|
613 |
+
points : tuple of ndarray of float, with shapes (m1, ), ..., (mn, )
|
614 |
+
The points defining the regular grid in n dimensions. The points in
|
615 |
+
each dimension (i.e. every elements of the points tuple) must be
|
616 |
+
strictly ascending or descending.
|
617 |
+
|
618 |
+
values : array_like, shape (m1, ..., mn, ...)
|
619 |
+
The data on the regular grid in n dimensions. Complex data is
|
620 |
+
accepted.
|
621 |
+
|
622 |
+
.. deprecated:: 1.13.0
|
623 |
+
Complex data is deprecated with ``method="pchip"`` and will raise an
|
624 |
+
error in SciPy 1.15.0. This is because ``PchipInterpolator`` only
|
625 |
+
works with real values. If you are trying to use the real components of
|
626 |
+
the passed array, use ``np.real`` on ``values``.
|
627 |
+
|
628 |
+
xi : ndarray of shape (..., ndim)
|
629 |
+
The coordinates to sample the gridded data at
|
630 |
+
|
631 |
+
method : str, optional
|
632 |
+
The method of interpolation to perform. Supported are "linear",
|
633 |
+
"nearest", "slinear", "cubic", "quintic", "pchip", and "splinef2d".
|
634 |
+
"splinef2d" is only supported for 2-dimensional data.
|
635 |
+
|
636 |
+
bounds_error : bool, optional
|
637 |
+
If True, when interpolated values are requested outside of the
|
638 |
+
domain of the input data, a ValueError is raised.
|
639 |
+
If False, then `fill_value` is used.
|
640 |
+
|
641 |
+
fill_value : number, optional
|
642 |
+
If provided, the value to use for points outside of the
|
643 |
+
interpolation domain. If None, values outside
|
644 |
+
the domain are extrapolated. Extrapolation is not supported by method
|
645 |
+
"splinef2d".
|
646 |
+
|
647 |
+
Returns
|
648 |
+
-------
|
649 |
+
values_x : ndarray, shape xi.shape[:-1] + values.shape[ndim:]
|
650 |
+
Interpolated values at `xi`. See notes for behaviour when
|
651 |
+
``xi.ndim == 1``.
|
652 |
+
|
653 |
+
See Also
|
654 |
+
--------
|
655 |
+
NearestNDInterpolator : Nearest neighbor interpolation on unstructured
|
656 |
+
data in N dimensions
|
657 |
+
LinearNDInterpolator : Piecewise linear interpolant on unstructured data
|
658 |
+
in N dimensions
|
659 |
+
RegularGridInterpolator : interpolation on a regular or rectilinear grid
|
660 |
+
in arbitrary dimensions (`interpn` wraps this
|
661 |
+
class).
|
662 |
+
RectBivariateSpline : Bivariate spline approximation over a rectangular mesh
|
663 |
+
scipy.ndimage.map_coordinates : interpolation on grids with equal spacing
|
664 |
+
(suitable for e.g., N-D image resampling)
|
665 |
+
|
666 |
+
Notes
|
667 |
+
-----
|
668 |
+
|
669 |
+
.. versionadded:: 0.14
|
670 |
+
|
671 |
+
In the case that ``xi.ndim == 1`` a new axis is inserted into
|
672 |
+
the 0 position of the returned array, values_x, so its shape is
|
673 |
+
instead ``(1,) + values.shape[ndim:]``.
|
674 |
+
|
675 |
+
If the input data is such that input dimensions have incommensurate
|
676 |
+
units and differ by many orders of magnitude, the interpolant may have
|
677 |
+
numerical artifacts. Consider rescaling the data before interpolation.
|
678 |
+
|
679 |
+
Examples
|
680 |
+
--------
|
681 |
+
Evaluate a simple example function on the points of a regular 3-D grid:
|
682 |
+
|
683 |
+
>>> import numpy as np
|
684 |
+
>>> from scipy.interpolate import interpn
|
685 |
+
>>> def value_func_3d(x, y, z):
|
686 |
+
... return 2 * x + 3 * y - z
|
687 |
+
>>> x = np.linspace(0, 4, 5)
|
688 |
+
>>> y = np.linspace(0, 5, 6)
|
689 |
+
>>> z = np.linspace(0, 6, 7)
|
690 |
+
>>> points = (x, y, z)
|
691 |
+
>>> values = value_func_3d(*np.meshgrid(*points, indexing='ij'))
|
692 |
+
|
693 |
+
Evaluate the interpolating function at a point
|
694 |
+
|
695 |
+
>>> point = np.array([2.21, 3.12, 1.15])
|
696 |
+
>>> print(interpn(points, values, point))
|
697 |
+
[12.63]
|
698 |
+
|
699 |
+
"""
|
700 |
+
# sanity check 'method' kwarg
|
701 |
+
if method not in ["linear", "nearest", "cubic", "quintic", "pchip",
|
702 |
+
"splinef2d", "slinear",
|
703 |
+
"slinear_legacy", "cubic_legacy", "quintic_legacy"]:
|
704 |
+
raise ValueError("interpn only understands the methods 'linear', "
|
705 |
+
"'nearest', 'slinear', 'cubic', 'quintic', 'pchip', "
|
706 |
+
f"and 'splinef2d'. You provided {method}.")
|
707 |
+
|
708 |
+
if not hasattr(values, 'ndim'):
|
709 |
+
values = np.asarray(values)
|
710 |
+
|
711 |
+
ndim = values.ndim
|
712 |
+
if ndim > 2 and method == "splinef2d":
|
713 |
+
raise ValueError("The method splinef2d can only be used for "
|
714 |
+
"2-dimensional input data")
|
715 |
+
if not bounds_error and fill_value is None and method == "splinef2d":
|
716 |
+
raise ValueError("The method splinef2d does not support extrapolation.")
|
717 |
+
|
718 |
+
# sanity check consistency of input dimensions
|
719 |
+
if len(points) > ndim:
|
720 |
+
raise ValueError("There are %d point arrays, but values has %d "
|
721 |
+
"dimensions" % (len(points), ndim))
|
722 |
+
if len(points) != ndim and method == 'splinef2d':
|
723 |
+
raise ValueError("The method splinef2d can only be used for "
|
724 |
+
"scalar data with one point per coordinate")
|
725 |
+
|
726 |
+
grid, descending_dimensions = _check_points(points)
|
727 |
+
_check_dimensionality(grid, values)
|
728 |
+
|
729 |
+
# sanity check requested xi
|
730 |
+
xi = _ndim_coords_from_arrays(xi, ndim=len(grid))
|
731 |
+
if xi.shape[-1] != len(grid):
|
732 |
+
raise ValueError("The requested sample points xi have dimension "
|
733 |
+
"%d, but this RegularGridInterpolator has "
|
734 |
+
"dimension %d" % (xi.shape[-1], len(grid)))
|
735 |
+
|
736 |
+
if bounds_error:
|
737 |
+
for i, p in enumerate(xi.T):
|
738 |
+
if not np.logical_and(np.all(grid[i][0] <= p),
|
739 |
+
np.all(p <= grid[i][-1])):
|
740 |
+
raise ValueError("One of the requested xi is out of bounds "
|
741 |
+
"in dimension %d" % i)
|
742 |
+
|
743 |
+
# perform interpolation
|
744 |
+
if method in RegularGridInterpolator._ALL_METHODS:
|
745 |
+
interp = RegularGridInterpolator(points, values, method=method,
|
746 |
+
bounds_error=bounds_error,
|
747 |
+
fill_value=fill_value)
|
748 |
+
return interp(xi)
|
749 |
+
elif method == "splinef2d":
|
750 |
+
xi_shape = xi.shape
|
751 |
+
xi = xi.reshape(-1, xi.shape[-1])
|
752 |
+
|
753 |
+
# RectBivariateSpline doesn't support fill_value; we need to wrap here
|
754 |
+
idx_valid = np.all((grid[0][0] <= xi[:, 0], xi[:, 0] <= grid[0][-1],
|
755 |
+
grid[1][0] <= xi[:, 1], xi[:, 1] <= grid[1][-1]),
|
756 |
+
axis=0)
|
757 |
+
result = np.empty_like(xi[:, 0])
|
758 |
+
|
759 |
+
# make a copy of values for RectBivariateSpline
|
760 |
+
interp = RectBivariateSpline(points[0], points[1], values[:])
|
761 |
+
result[idx_valid] = interp.ev(xi[idx_valid, 0], xi[idx_valid, 1])
|
762 |
+
result[np.logical_not(idx_valid)] = fill_value
|
763 |
+
|
764 |
+
return result.reshape(xi_shape[:-1])
|
765 |
+
else:
|
766 |
+
raise ValueError(f"unknown {method = }")
|
env-llmeval/lib/python3.10/site-packages/scipy/interpolate/_rgi_cython.cpython-310-x86_64-linux-gnu.so
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|
|
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|
|
env-llmeval/lib/python3.10/site-packages/scipy/interpolate/fitpack.py
ADDED
@@ -0,0 +1,32 @@
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
1 |
+
# This file is not meant for public use and will be removed in SciPy v2.0.0.
|
2 |
+
# Use the `scipy.interpolate` namespace for importing the functions
|
3 |
+
# included below.
|
4 |
+
|
5 |
+
from scipy._lib.deprecation import _sub_module_deprecation
|
6 |
+
|
7 |
+
|
8 |
+
__all__ = [ # noqa: F822
|
9 |
+
'BSpline',
|
10 |
+
'bisplev',
|
11 |
+
'bisplrep',
|
12 |
+
'dblint',
|
13 |
+
'insert',
|
14 |
+
'spalde',
|
15 |
+
'splantider',
|
16 |
+
'splder',
|
17 |
+
'splev',
|
18 |
+
'splint',
|
19 |
+
'splprep',
|
20 |
+
'splrep',
|
21 |
+
'sproot',
|
22 |
+
]
|
23 |
+
|
24 |
+
|
25 |
+
def __dir__():
|
26 |
+
return __all__
|
27 |
+
|
28 |
+
|
29 |
+
def __getattr__(name):
|
30 |
+
return _sub_module_deprecation(sub_package="interpolate", module="fitpack",
|
31 |
+
private_modules=["_fitpack_py"], all=__all__,
|
32 |
+
attribute=name)
|
env-llmeval/lib/python3.10/site-packages/scipy/interpolate/ndgriddata.py
ADDED
@@ -0,0 +1,25 @@
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
1 |
+
# This file is not meant for public use and will be removed in SciPy v2.0.0.
|
2 |
+
# Use the `scipy.interpolate` namespace for importing the functions
|
3 |
+
# included below.
|
4 |
+
|
5 |
+
from scipy._lib.deprecation import _sub_module_deprecation
|
6 |
+
|
7 |
+
|
8 |
+
__all__ = [ # noqa: F822
|
9 |
+
'CloughTocher2DInterpolator',
|
10 |
+
'LinearNDInterpolator',
|
11 |
+
'NDInterpolatorBase',
|
12 |
+
'NearestNDInterpolator',
|
13 |
+
'cKDTree',
|
14 |
+
'griddata',
|
15 |
+
]
|
16 |
+
|
17 |
+
|
18 |
+
def __dir__():
|
19 |
+
return __all__
|
20 |
+
|
21 |
+
|
22 |
+
def __getattr__(name):
|
23 |
+
return _sub_module_deprecation(sub_package="interpolate", module="ndgriddata",
|
24 |
+
private_modules=["_ndgriddata"], all=__all__,
|
25 |
+
attribute=name)
|
env-llmeval/lib/python3.10/site-packages/scipy/interpolate/rbf.py
ADDED
@@ -0,0 +1,25 @@
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
1 |
+
# This file is not meant for public use and will be removed in SciPy v2.0.0.
|
2 |
+
# Use the `scipy.interpolate` namespace for importing the functions
|
3 |
+
# included below.
|
4 |
+
|
5 |
+
from scipy._lib.deprecation import _sub_module_deprecation
|
6 |
+
|
7 |
+
|
8 |
+
__all__ = [ # noqa: F822
|
9 |
+
'Rbf',
|
10 |
+
'cdist',
|
11 |
+
'linalg',
|
12 |
+
'pdist',
|
13 |
+
'squareform',
|
14 |
+
'xlogy',
|
15 |
+
]
|
16 |
+
|
17 |
+
|
18 |
+
def __dir__():
|
19 |
+
return __all__
|
20 |
+
|
21 |
+
|
22 |
+
def __getattr__(name):
|
23 |
+
return _sub_module_deprecation(sub_package="interpolate", module="rbf",
|
24 |
+
private_modules=["_rbf"], all=__all__,
|
25 |
+
attribute=name)
|
env-llmeval/lib/python3.10/site-packages/scipy/interpolate/tests/__init__.py
ADDED
File without changes
|
env-llmeval/lib/python3.10/site-packages/scipy/interpolate/tests/__pycache__/__init__.cpython-310.pyc
ADDED
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|
|
env-llmeval/lib/python3.10/site-packages/scipy/interpolate/tests/__pycache__/test_bsplines.cpython-310.pyc
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|
|
env-llmeval/lib/python3.10/site-packages/scipy/interpolate/tests/__pycache__/test_fitpack.cpython-310.pyc
ADDED
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|
|
env-llmeval/lib/python3.10/site-packages/scipy/interpolate/tests/__pycache__/test_fitpack2.cpython-310.pyc
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|
|
env-llmeval/lib/python3.10/site-packages/scipy/interpolate/tests/__pycache__/test_gil.cpython-310.pyc
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|
|
env-llmeval/lib/python3.10/site-packages/scipy/interpolate/tests/__pycache__/test_interpnd.cpython-310.pyc
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|
|
env-llmeval/lib/python3.10/site-packages/scipy/interpolate/tests/__pycache__/test_interpolate.cpython-310.pyc
ADDED
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|
|
env-llmeval/lib/python3.10/site-packages/scipy/interpolate/tests/__pycache__/test_ndgriddata.cpython-310.pyc
ADDED
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|
|
env-llmeval/lib/python3.10/site-packages/scipy/interpolate/tests/__pycache__/test_pade.cpython-310.pyc
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|
|
env-llmeval/lib/python3.10/site-packages/scipy/interpolate/tests/__pycache__/test_polyint.cpython-310.pyc
ADDED
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|
|
env-llmeval/lib/python3.10/site-packages/scipy/interpolate/tests/__pycache__/test_rbf.cpython-310.pyc
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|
|
env-llmeval/lib/python3.10/site-packages/scipy/interpolate/tests/__pycache__/test_rbfinterp.cpython-310.pyc
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|
|