code
string | signature
string | docstring
string | loss_without_docstring
float64 | loss_with_docstring
float64 | factor
float64 |
---|---|---|---|---|---|
return numpy.log10(evaluation.evaluate_bound(
dist, 10**xloc, cache=cache)) | def _bnd(self, xloc, dist, cache) | Distribution bounds. | 11.143881 | 10.871576 | 1.025047 |
dim = len(dist)
if poly.dim < dim:
poly = chaospy.poly.setdim(poly, len(dist))
zero = [1]*dim
out = numpy.zeros((dim,) + poly.shape, dtype=float)
V = Var(poly, dist, **kws)
for i in range(dim):
zero[i] = 0
out[i] = ((V-Var(E_cond(poly, zero, dist, **kws), dist, **kws)) /
(V+(V == 0))**(V!=0))
zero[i] = 1
return out | def Sens_t(poly, dist, **kws) | Variance-based decomposition
AKA Sobol' indices
Total effect sensitivity index
Args:
poly (Poly):
Polynomial to find first order Sobol indices on.
dist (Dist):
The distributions of the input used in ``poly``.
Returns:
(numpy.ndarray) :
First order sensitivity indices for each parameters in ``poly``,
with shape ``(len(dist),) + poly.shape``.
Examples:
>>> x, y = chaospy.variable(2)
>>> poly = chaospy.Poly([1, x, y, 10*x*y])
>>> dist = chaospy.Iid(chaospy.Uniform(0, 1), 2)
>>> indices = chaospy.Sens_t(poly, dist)
>>> print(indices)
[[0. 1. 0. 0.57142857]
[0. 0. 1. 0.57142857]] | 4.725328 | 5.008917 | 0.943383 |
for key in kwargs:
assert key in LEGAL_ATTRS, "{} is not legal input".format(key)
if parent is not None:
for key, value in LEGAL_ATTRS.items():
if key not in kwargs and hasattr(parent, value):
kwargs[key] = getattr(parent, value)
assert "cdf" in kwargs, "cdf function must be defined"
assert "bnd" in kwargs, "bnd function must be defined"
if "str" in kwargs and isinstance(kwargs["str"], str):
string = kwargs.pop("str")
kwargs["str"] = lambda *args, **kwargs: string
defaults = defaults if defaults else {}
for key in defaults:
assert key in LEGAL_ATTRS, "invalid default value {}".format(key)
def custom_distribution(**kws):
prm = defaults.copy()
prm.update(kws)
dist = Dist(**prm)
for key, function in kwargs.items():
attr_name = LEGAL_ATTRS[key]
setattr(dist, attr_name, types.MethodType(function, dist))
return dist
if "doc" in kwargs:
custom_distribution.__doc__ = kwargs["doc"]
return custom_distribution | def construct(parent=None, defaults=None, **kwargs) | Random variable constructor.
Args:
cdf:
Cumulative distribution function. Optional if ``parent`` is used.
bnd:
Boundary interval. Optional if ``parent`` is used.
parent (Dist):
Distribution used as basis for new distribution. Any other argument
that is omitted will instead take is function from ``parent``.
doc (str]):
Documentation for the distribution.
str (str, :py:data:typing.Callable):
Pretty print of the variable.
pdf:
Probability density function.
ppf:
Point percentile function.
mom:
Raw moment generator.
ttr:
Three terms recursion coefficient generator.
init:
Custom initialiser method.
defaults (dict):
Default values to provide to initialiser.
Returns:
(Dist):
New custom distribution. | 2.917506 | 2.807802 | 1.039071 |
return evaluation.evaluate_density(
dist, numpy.arctan(x), cache=cache)/(1+x*x) | def _pdf(self, x, dist, cache) | Probability density function. | 11.441137 | 11.465957 | 0.997835 |
orth = chaospy.poly.Poly(orth)
nodes = numpy.asfarray(nodes)
weights = numpy.asfarray(weights)
if callable(solves):
solves = [solves(node) for node in nodes.T]
solves = numpy.asfarray(solves)
shape = solves.shape
solves = solves.reshape(weights.size, int(solves.size/weights.size))
ovals = orth(*nodes)
vals1 = [(val*solves.T*weights).T for val in ovals]
if norms is None:
norms = numpy.sum(ovals**2*weights, -1)
else:
norms = numpy.array(norms).flatten()
assert len(norms) == len(orth)
coefs = (numpy.sum(vals1, 1).T/norms).T
coefs = coefs.reshape(len(coefs), *shape[1:])
approx_model = chaospy.poly.transpose(chaospy.poly.sum(orth*coefs.T, -1))
if retall:
return approx_model, coefs
return approx_model | def fit_quadrature(orth, nodes, weights, solves, retall=False, norms=None, **kws) | Using spectral projection to create a polynomial approximation over
distribution space.
Args:
orth (chaospy.poly.base.Poly):
Orthogonal polynomial expansion. Must be orthogonal for the
approximation to be accurate.
nodes (numpy.ndarray):
Where to evaluate the polynomial expansion and model to
approximate. ``nodes.shape==(D,K)`` where ``D`` is the number of
dimensions and ``K`` is the number of nodes.
weights (numpy.ndarray):
Weights when doing numerical integration. ``weights.shape == (K,)``
must hold.
solves (numpy.ndarray):
The model evaluation to approximate. If `numpy.ndarray` is
provided, it must have ``len(solves) == K``. If callable, it must
take a single argument X with ``len(X) == D``, and return
a consistent numpy compatible shape.
norms (numpy.ndarray):
In the of TTR using coefficients to estimate the polynomial norm is
more stable than manual calculation. Calculated using quadrature if
no provided. ``norms.shape == (len(orth),)`` must hold.
Returns:
(chaospy.poly.base.Poly):
Fitted model approximation in the form of an polynomial. | 3.146378 | 2.938619 | 1.070699 |
if not isinstance(order, int):
orders = numpy.array(order).flatten()
dim = orders.size
m_order = int(numpy.min(orders))
skew = [order-m_order for order in orders]
return sparse_grid(func, m_order, dim, skew)
abscissas, weights = [], []
bindex = chaospy.bertran.bindex(order-dim+1, order, dim)
if skew is None:
skew = numpy.zeros(dim, dtype=int)
else:
skew = numpy.array(skew, dtype=int)
assert len(skew) == dim
for idx in range(
chaospy.bertran.terms(order, dim)
- chaospy.bertran.terms(order-dim, dim)):
idb = bindex[idx]
abscissa, weight = func(skew+idb)
weight *= (-1)**(order-sum(idb))*comb(dim-1, order-sum(idb))
abscissas.append(abscissa)
weights.append(weight)
abscissas = numpy.concatenate(abscissas, 1)
weights = numpy.concatenate(weights, 0)
abscissas = numpy.around(abscissas, 15)
order = numpy.lexsort(tuple(abscissas))
abscissas = abscissas.T[order].T
weights = weights[order]
# identify non-unique terms
diff = numpy.diff(abscissas.T, axis=0)
unique = numpy.ones(len(abscissas.T), bool)
unique[1:] = (diff != 0).any(axis=1)
# merge duplicate nodes
length = len(weights)
idx = 1
while idx < length:
while idx < length and unique[idx]:
idx += 1
idy = idx+1
while idy < length and not unique[idy]:
idy += 1
if idy-idx > 1:
weights[idx-1] = numpy.sum(weights[idx-1:idy])
idx = idy+1
abscissas = abscissas[:, unique]
weights = weights[unique]
return abscissas, weights | def sparse_grid(func, order, dim=None, skew=None) | Smolyak sparse grid constructor.
Args:
func (:py:data:typing.Callable):
Function that takes a single argument ``order`` of type
``numpy.ndarray`` and with ``order.shape = (dim,)``
order (int, numpy.ndarray):
The order of the grid. If ``numpy.ndarray``, it overrides both
``dim`` and ``skew``.
dim (int):
Number of dimension.
skew (list):
Order skewness. | 2.760751 | 2.802157 | 0.985224 |
assert len(x_data) == len(distribution)
assert len(x_data.shape) == 2
cache = cache if cache is not None else {}
parameters = load_parameters(
distribution, "_bnd", parameters=parameters, cache=cache)
out = numpy.zeros((2,) + x_data.shape)
lower, upper = distribution._bnd(x_data.copy(), **parameters)
out.T[:, :, 0] = numpy.asfarray(lower).T
out.T[:, :, 1] = numpy.asfarray(upper).T
cache[distribution] = out
return out | def evaluate_bound(
distribution,
x_data,
parameters=None,
cache=None,
) | Evaluate lower and upper bounds.
Args:
distribution (Dist):
Distribution to evaluate.
x_data (numpy.ndarray):
Locations for where evaluate bounds at. Relevant in the case of
multivariate distributions where the bounds are affected by the
output of other distributions.
parameters (:py:data:typing.Any):
Collection of parameters to override the default ones in the
distribution.
cache (:py:data:typing.Any):
A collection of previous calculations in case the same distribution
turns up on more than one occasion.
Returns:
The lower and upper bounds of ``distribution`` at location
``x_data`` using parameters ``parameters``. | 3.554734 | 3.421045 | 1.039079 |
haspoly = sum([isinstance(arg, Poly) for arg in args])
# Numpy
if not haspoly:
return numpy.sum(numpy.prod(args, 0), 0)
# Poly
out = args[0]
for arg in args[1:]:
out = out * arg
return sum(out) | def inner(*args) | Inner product of a polynomial set.
Args:
args (chaospy.poly.base.Poly):
The polynomials to perform inner product on.
Returns:
(chaospy.poly.base.Poly):
Resulting polynomial.
Examples:
>>> x,y = cp.variable(2)
>>> P = cp.Poly([x-1, y])
>>> Q = cp.Poly([x+1, x*y])
>>> print(cp.inner(P, Q))
q0^2+q0q1^2-1
>>> x = numpy.arange(4)
>>> print(cp.inner(x, x))
14 | 4.71994 | 7.181394 | 0.657246 |
if len(args) > 2:
part1 = args[0]
part2 = outer(*args[1:])
elif len(args) == 2:
part1, part2 = args
else:
return args[0]
dtype = chaospy.poly.typing.dtyping(part1, part2)
if dtype in (list, tuple, numpy.ndarray):
part1 = numpy.array(part1)
part2 = numpy.array(part2)
shape = part1.shape + part2.shape
return numpy.outer(
chaospy.poly.shaping.flatten(part1),
chaospy.poly.shaping.flatten(part2),
)
if dtype == Poly:
if isinstance(part1, Poly) and isinstance(part2, Poly):
if (1,) in (part1.shape, part2.shape):
return part1*part2
shape = part1.shape+part2.shape
out = []
for _ in chaospy.poly.shaping.flatten(part1):
out.append(part2*_)
return chaospy.poly.shaping.reshape(Poly(out), shape)
if isinstance(part1, (int, float, list, tuple)):
part2, part1 = numpy.array(part1), part2
else:
part2 = numpy.array(part2)
core_old = part1.A
core_new = {}
for key in part1.keys:
core_new[key] = outer(core_old[key], part2)
shape = part1.shape+part2.shape
dtype = chaospy.poly.typing.dtyping(part1.dtype, part2.dtype)
return Poly(core_new, part1.dim, shape, dtype)
raise NotImplementedError | def outer(*args) | Polynomial outer product.
Args:
P1 (chaospy.poly.base.Poly, numpy.ndarray):
First term in outer product
P2 (chaospy.poly.base.Poly, numpy.ndarray):
Second term in outer product
Returns:
(chaospy.poly.base.Poly):
Poly set with same dimensions as itter.
Examples:
>>> x = cp.variable()
>>> P = cp.prange(3)
>>> print(P)
[1, q0, q0^2]
>>> print(cp.outer(x, P))
[q0, q0^2, q0^3]
>>> print(cp.outer(P, P))
[[1, q0, q0^2], [q0, q0^2, q0^3], [q0^2, q0^3, q0^4]] | 2.777348 | 2.770744 | 1.002383 |
if not isinstance(poly1, Poly) and not isinstance(poly2, Poly):
return numpy.dot(poly1, poly2)
poly1 = Poly(poly1)
poly2 = Poly(poly2)
poly = poly1*poly2
if numpy.prod(poly1.shape) <= 1 or numpy.prod(poly2.shape) <= 1:
return poly
return chaospy.poly.sum(poly, 0) | def dot(poly1, poly2) | Dot product of polynomial vectors.
Args:
poly1 (Poly) : left part of product.
poly2 (Poly) : right part of product.
Returns:
(Poly) : product of poly1 and poly2.
Examples:
>>> poly = cp.prange(3, 1)
>>> print(poly)
[1, q0, q0^2]
>>> print(cp.dot(poly, numpy.arange(3)))
2q0^2+q0
>>> print(cp.dot(poly, poly))
q0^4+q0^2+1 | 2.772937 | 3.216313 | 0.862148 |
order = sorted(GENZ_KEISTER_16.keys())[order]
abscissas, weights = GENZ_KEISTER_16[order]
abscissas = numpy.array(abscissas)
weights = numpy.array(weights)
weights /= numpy.sum(weights)
abscissas *= numpy.sqrt(2)
return abscissas, weights | def quad_genz_keister_16(order) | Hermite Genz-Keister 16 rule.
Args:
order (int):
The quadrature order. Must be in the interval (0, 8).
Returns:
(:py:data:typing.Tuple[numpy.ndarray, numpy.ndarray]):
Abscissas and weights
Examples:
>>> abscissas, weights = quad_genz_keister_16(1)
>>> print(numpy.around(abscissas, 4))
[-1.7321 0. 1.7321]
>>> print(numpy.around(weights, 4))
[0.1667 0.6667 0.1667] | 2.614681 | 3.60144 | 0.72601 |
output = evaluation.evaluate_density(dist, numpy.arccosh(x), cache=cache)
output /= numpy.where(x != 1, numpy.sqrt(x*x-1), numpy.inf)
return output | def _pdf(self, x, dist, cache) | Probability density function. | 6.18156 | 6.430818 | 0.96124 |
logger = logging.getLogger(__name__)
dim = len(dist)
if isinstance(order, int):
if order == 0:
return chaospy.poly.Poly(1, dim=dim)
basis = chaospy.poly.basis(
0, order, dim, sort, cross_truncation=cross_truncation)
else:
basis = order
basis = list(basis)
polynomials = [basis[0]]
if normed:
for idx in range(1, len(basis)):
# orthogonalize polynomial:
for idy in range(idx):
orth = chaospy.descriptives.E(
basis[idx]*polynomials[idy], dist, **kws)
basis[idx] = basis[idx] - polynomials[idy]*orth
# normalize:
norms = chaospy.descriptives.E(polynomials[-1]**2, dist, **kws)
if norms <= 0:
logger.warning("Warning: Polynomial cutoff at term %d", idx)
break
basis[idx] = basis[idx] / numpy.sqrt(norms)
polynomials.append(basis[idx])
else:
norms = [1.]
for idx in range(1, len(basis)):
# orthogonalize polynomial:
for idy in range(idx):
orth = chaospy.descriptives.E(
basis[idx]*polynomials[idy], dist, **kws)
basis[idx] = basis[idx] - polynomials[idy] * orth / norms[idy]
norms.append(
chaospy.descriptives.E(polynomials[-1]**2, dist, **kws))
if norms[-1] <= 0:
logger.warning("Warning: Polynomial cutoff at term %d", idx)
break
polynomials.append(basis[idx])
return chaospy.poly.Poly(polynomials, dim=dim, shape=(len(polynomials),)) | def orth_gs(order, dist, normed=False, sort="GR", cross_truncation=1., **kws) | Gram-Schmidt process for generating orthogonal polynomials.
Args:
order (int, Poly):
The upper polynomial order. Alternative a custom polynomial basis
can be used.
dist (Dist):
Weighting distribution(s) defining orthogonality.
normed (bool):
If True orthonormal polynomials will be used instead of monic.
sort (str):
Ordering argument passed to poly.basis. If custom basis is used,
argument is ignored.
cross_truncation (float):
Use hyperbolic cross truncation scheme to reduce the number of
terms in expansion.
Returns:
(Poly):
The orthogonal polynomial expansion.
Examples:
>>> Z = chaospy.J(chaospy.Normal(), chaospy.Normal())
>>> print(chaospy.around(chaospy.orth_gs(2, Z), 4))
[1.0, q1, q0, q1^2-1.0, q0q1, q0^2-1.0] | 2.43097 | 2.45714 | 0.989349 |
from .. import baseclass
if cache is None:
cache = {}
if parameters is None:
parameters = {}
parameters_ = distribution.prm.copy()
parameters_.update(**parameters)
parameters = parameters_
# self aware and should handle things itself:
if contains_call_signature(getattr(distribution, method_name), "cache"):
parameters["cache"] = cache
# dumb distribution and just wants to evaluate:
else:
for key, value in parameters.items():
if isinstance(value, baseclass.Dist):
value = cache_key(value)
if value in cache:
parameters[key] = cache[value]
else:
raise baseclass.StochasticallyDependentError(
"evaluating under-defined distribution {}.".format(distribution))
return parameters | def load_parameters(
distribution,
method_name,
parameters=None,
cache=None,
cache_key=lambda x:x,
) | Load parameter values by filling them in from cache.
Args:
distribution (Dist):
The distribution to load parameters from.
method_name (str):
Name of the method for where the parameters should be used.
Typically ``"_pdf"``, ``_cdf`` or the like.
parameters (:py:data:typing.Any):
Default parameters to use if there are no cache to retrieve. Use
the distributions internal parameters, if not provided.
cache (:py:data:typing.Any):
A dictionary containing previous evaluations from the stack. If
a parameters contains a distribution that contains in the cache, it
will be replaced with the cache value. If omitted, a new one will
be created.
cache_key (:py:data:typing.Any)
Redefine the keys of the cache to suite other purposes.
Returns:
Same as ``parameters``, if provided. The ``distribution`` parameter if
not. In either case, parameters may be updated with cache values (if
provided) or by ``cache`` if the call signature of ``method_name`` (on
``distribution``) contains an ``cache`` argument. | 6.18969 | 5.913178 | 1.046762 |
order = sorted(GENZ_KEISTER_18.keys())[order]
abscissas, weights = GENZ_KEISTER_18[order]
abscissas = numpy.array(abscissas)
weights = numpy.array(weights)
weights /= numpy.sum(weights)
abscissas *= numpy.sqrt(2)
return abscissas, weights | def quad_genz_keister_18(order) | Hermite Genz-Keister 18 rule.
Args:
order (int):
The quadrature order. Must be in the interval (0, 8).
Returns:
(:py:data:typing.Tuple[numpy.ndarray, numpy.ndarray]):
Abscissas and weights
Examples:
>>> abscissas, weights = quad_genz_keister_18(1)
>>> print(numpy.around(abscissas, 4))
[-1.7321 0. 1.7321]
>>> print(numpy.around(weights, 4))
[0.1667 0.6667 0.1667] | 2.628624 | 3.663012 | 0.717613 |
args = list(args)
for idx, arg in enumerate(args):
if isinstance(arg, Poly):
args[idx] = Poly
elif isinstance(arg, numpy.generic):
args[idx] = numpy.asarray(arg).dtype
elif isinstance(arg, (float, int)):
args[idx] = type(arg)
for type_ in DATATYPES:
if type_ in args:
return type_
raise ValueError(
"dtypes not recognised " + str([str(_) for _ in args])) | def dtyping(*args) | Find least common denominator dtype.
Examples:
>>> str(dtyping(int, float)) in ("<class 'float'>", "<type 'float'>")
True
>>> print(dtyping(int, Poly))
<class 'chaospy.poly.base.Poly'> | 3.590744 | 3.664485 | 0.979877 |
if limit is None:
limit = 10**300
if isinstance(vari, Poly):
core = vari.A.copy()
for key in vari.keys:
core[key] = core[key]*1.
return Poly(core, vari.dim, vari.shape, float)
return numpy.asfarray(vari) | def asfloat(vari, limit=None) | Convert dtype of polynomial coefficients to float.
Example:
>>> poly = 2*cp.variable()+1
>>> print(poly)
2q0+1
>>> print(cp.asfloat(poly))
2.0q0+1.0 | 5.470446 | 6.028703 | 0.9074 |
if isinstance(vari, Poly):
core = vari.A.copy()
for key in vari.keys:
core[key] = numpy.asarray(core[key], dtype=int)
return Poly(core, vari.dim, vari.shape, int)
return numpy.asarray(vari, dtype=int) | def asint(vari) | Convert dtype of polynomial coefficients to float.
Example:
>>> poly = 1.5*cp.variable()+2.25
>>> print(poly)
1.5q0+2.25
>>> print(cp.asint(poly))
q0+2 | 5.087651 | 5.956754 | 0.854098 |
if isinstance(vari, Poly):
shape = vari.shape
out = numpy.asarray(
[{} for _ in range(numpy.prod(shape))],
dtype=object
)
core = vari.A.copy()
for key in core.keys():
core[key] = core[key].flatten()
for i in range(numpy.prod(shape)):
if not numpy.all(core[key][i] == 0):
out[i][key] = core[key][i]
for i in range(numpy.prod(shape)):
out[i] = Poly(out[i], vari.dim, (), vari.dtype)
out = out.reshape(shape)
return out
return numpy.asarray(vari) | def toarray(vari) | Convert polynomial array into a numpy.asarray of polynomials.
Args:
vari (Poly, numpy.ndarray):
Input data.
Returns:
(numpy.ndarray):
A numpy array with ``Q.shape==A.shape``.
Examples:
>>> poly = cp.prange(3)
>>> print(poly)
[1, q0, q0^2]
>>> array = cp.toarray(poly)
>>> print(isinstance(array, numpy.ndarray))
True
>>> print(array[1])
q0 | 3.279006 | 3.255975 | 1.007074 |
output = evaluation.evaluate_density(
dist, xloc.reshape(1, -1)).reshape(length, -1)
assert xloc.shape == output.shape
return output | def _pdf(self, xloc, dist, length, cache) | Probability density function.
Example:
>>> print(chaospy.Iid(chaospy.Uniform(), 2).pdf(
... [[0.5, 1.5], [0.5, 0.5]]))
[1. 0.] | 6.091562 | 13.068237 | 0.466135 |
output = evaluation.evaluate_forward(
dist, xloc.reshape(1, -1)).reshape(length, -1)
assert xloc.shape == output.shape
return output | def _cdf(self, xloc, dist, length, cache) | Cumulative distribution function.
Example:
>>> print(chaospy.Iid(chaospy.Uniform(0, 2), 2).fwd(
... [[0.1, 0.2, 0.3], [0.2, 0.2, 0.3]]))
[[0.05 0.1 0.15]
[0.1 0.1 0.15]] | 6.629615 | 10.454229 | 0.634156 |
output = evaluation.evaluate_inverse(
dist, uloc.reshape(1, -1)).reshape(length, -1)
assert uloc.shape == output.shape
return output | def _ppf(self, uloc, dist, length, cache) | Point percentile function.
Example:
>>> print(chaospy.Iid(chaospy.Uniform(0, 2), 2).inv(
... [[0.1, 0.2, 0.3], [0.2, 0.2, 0.3]]))
[[0.2 0.4 0.6]
[0.4 0.4 0.6]] | 6.276289 | 10.344861 | 0.606706 |
lower, upper = evaluation.evaluate_bound(
dist, xloc.reshape(1, -1))
lower = lower.reshape(length, -1)
upper = upper.reshape(length, -1)
assert lower.shape == xloc.shape, (lower.shape, xloc.shape)
assert upper.shape == xloc.shape
return lower, upper | def _bnd(self, xloc, dist, length, cache) | boundary function.
Example:
>>> print(chaospy.Iid(chaospy.Uniform(0, 2), 2).range(
... [[0.1, 0.2, 0.3], [0.2, 0.2, 0.3]]))
[[[0. 0. 0.]
[0. 0. 0.]]
<BLANKLINE>
[[2. 2. 2.]
[2. 2. 2.]]] | 3.047548 | 3.599135 | 0.846744 |
return numpy.prod(dist.mom(k), 0) | def _mom(self, k, dist, length, cache) | Moment generating function.
Example:
>>> print(chaospy.Iid(chaospy.Uniform(), 2).mom(
... [[0, 0, 1], [0, 1, 1]]))
[1. 0.5 0.25] | 11.222154 | 13.542467 | 0.828664 |
assert len(x_data) == len(distribution)
assert len(x_data.shape) == 2
cache = cache if cache is not None else {}
out = numpy.zeros(x_data.shape)
# Distribution self know how to handle density evaluation.
if hasattr(distribution, "_pdf"):
parameters = load_parameters(
distribution, "_pdf", parameters=parameters, cache=cache)
out[:] = distribution._pdf(x_data, **parameters)
# Approximate density evaluation based on cumulative distribution function.
else:
from .. import approximation
parameters = load_parameters(
distribution, "_cdf", parameters=parameters, cache=cache)
out[:] = approximation.approximate_density(
distribution, x_data, parameters=parameters, cache=cache)
# dependency handling.
if distribution in cache:
out = numpy.where(x_data == cache[distribution], out, 0)
else:
cache[distribution] = x_data
return out | def evaluate_density(
distribution,
x_data,
parameters=None,
cache=None,
) | Evaluate probability density function (PDF).
Args:
distribution (Dist):
Distribution to evaluate.
x_data (numpy.ndarray):
Locations for where evaluate density at.
parameters (:py:data:typing.Any):
Collection of parameters to override the default ones in the
distribution.
cache (:py:data:typing.Any):
A collection of previous calculations in case the same distribution
turns up on more than one occasion.
Returns:
The probability density values of ``distribution`` at location
``x_data`` using parameters ``parameters``. | 3.325184 | 3.353857 | 0.991451 |
core = vari.A.copy()
for key in vari.keys:
core[key] = sum(core[key], axis)
return Poly(core, vari.dim, None, vari.dtype)
return np.sum(vari, axis) | def sum(vari, axis=None): # pylint: disable=redefined-builtin
if isinstance(vari, Poly) | Sum the components of a shapeable quantity along a given axis.
Args:
vari (chaospy.poly.base.Poly, numpy.ndarray):
Input data.
axis (int):
Axis over which the sum is taken. By default ``axis`` is None, and
all elements are summed.
Returns:
(chaospy.poly.base.Poly, numpy.ndarray):
Polynomial array with same shape as ``vari``, with the specified
axis removed. If ``vari`` is an 0-d array, or ``axis`` is None,
a (non-iterable) component is returned.
Examples:
>>> vari = cp.prange(3)
>>> print(vari)
[1, q0, q0^2]
>>> print(cp.sum(vari))
q0^2+q0+1 | 3.848225 | 10.085525 | 0.381559 |
if isinstance(vari, Poly):
core = vari.A.copy()
for key, val in core.items():
core[key] = cumsum(val, axis)
return Poly(core, vari.dim, None, vari.dtype)
return np.cumsum(vari, axis) | def cumsum(vari, axis=None) | Cumulative sum the components of a shapeable quantity along a given axis.
Args:
vari (chaospy.poly.base.Poly, numpy.ndarray):
Input data.
axis (int):
Axis over which the sum is taken. By default ``axis`` is None, and
all elements are summed.
Returns:
(chaospy.poly.base.Poly, numpy.ndarray):
Polynomial array with same shape as ``vari``.
Examples:
>>> poly = cp.prange(3)
>>> print(poly)
[1, q0, q0^2]
>>> print(cp.cumsum(poly))
[1, q0+1, q0^2+q0+1] | 3.995687 | 6.065583 | 0.658748 |
if isinstance(vari, Poly):
if axis is None:
vari = chaospy.poly.shaping.flatten(vari)
axis = 0
vari = chaospy.poly.shaping.rollaxis(vari, axis)
out = vari[0]
for poly in vari[1:]:
out = out*poly
return out
return np.prod(vari, axis) | def prod(vari, axis=None) | Product of the components of a shapeable quantity along a given axis.
Args:
vari (chaospy.poly.base.Poly, numpy.ndarray):
Input data.
axis (int):
Axis over which the sum is taken. By default ``axis`` is None, and
all elements are summed.
Returns:
(chaospy.poly.base.Poly, numpy.ndarray):
Polynomial array with same shape as ``vari``, with the specified
axis removed. If ``vari`` is an 0-d array, or ``axis`` is None,
a (non-iterable) component is returned.
Examples:
>>> vari = cp.prange(3)
>>> print(vari)
[1, q0, q0^2]
>>> print(cp.prod(vari))
q0^3 | 3.44522 | 3.754272 | 0.91768 |
if isinstance(vari, Poly):
if np.prod(vari.shape) == 1:
return vari.copy()
if axis is None:
vari = chaospy.poly.shaping.flatten(vari)
axis = 0
vari = chaospy.poly.shaping.rollaxis(vari, axis)
out = [vari[0]]
for poly in vari[1:]:
out.append(out[-1]*poly)
return Poly(out, vari.dim, vari.shape, vari.dtype)
return np.cumprod(vari, axis) | def cumprod(vari, axis=None) | Perform the cumulative product of a shapeable quantity over a given axis.
Args:
vari (chaospy.poly.base.Poly, numpy.ndarray):
Input data.
axis (int):
Axis over which the sum is taken. By default ``axis`` is None, and
all elements are summed.
Returns:
(chaospy.poly.base.Poly):
An array shaped as ``vari`` but with the specified axis removed.
Examples:
>>> vari = cp.prange(4)
>>> print(vari)
[1, q0, q0^2, q0^3]
>>> print(cp.cumprod(vari))
[1, q0, q0^3, q0^6] | 3.446298 | 3.655376 | 0.942802 |
from chaospy.distributions import evaluation
if len(dist) > 1 and evaluation.get_dependencies(*list(dist)):
raise evaluation.DependencyError(
"Leja quadrature do not supper distribution with dependencies.")
if len(dist) > 1:
if isinstance(order, int):
out = [quad_leja(order, _) for _ in dist]
else:
out = [quad_leja(order[_], dist[_]) for _ in range(len(dist))]
abscissas = [_[0][0] for _ in out]
weights = [_[1] for _ in out]
abscissas = chaospy.quad.combine(abscissas).T
weights = chaospy.quad.combine(weights)
weights = numpy.prod(weights, -1)
return abscissas, weights
lower, upper = dist.range()
abscissas = [lower, dist.mom(1), upper]
for _ in range(int(order)):
obj = create_objective(dist, abscissas)
opts, vals = zip(
*[fminbound(
obj, abscissas[idx], abscissas[idx+1], full_output=1)[:2]
for idx in range(len(abscissas)-1)]
)
index = numpy.argmin(vals)
abscissas.insert(index+1, opts[index])
abscissas = numpy.asfarray(abscissas).flatten()[1:-1]
weights = create_weights(abscissas, dist)
abscissas = abscissas.reshape(1, abscissas.size)
return numpy.array(abscissas), numpy.array(weights) | def quad_leja(order, dist) | Generate Leja quadrature node.
Example:
>>> abscisas, weights = quad_leja(3, chaospy.Normal(0, 1))
>>> print(numpy.around(abscisas, 4))
[[-2.7173 -1.4142 0. 1.7635]]
>>> print(numpy.around(weights, 4))
[0.022 0.1629 0.6506 0.1645] | 3.07805 | 3.063303 | 1.004814 |
abscissas_ = numpy.array(abscissas[1:-1])
def obj(absisa):
out = -numpy.sqrt(dist.pdf(absisa))
out *= numpy.prod(numpy.abs(abscissas_ - absisa))
return out
return obj | def create_objective(dist, abscissas) | Create objective function. | 4.990664 | 4.995146 | 0.999103 |
poly = chaospy.quad.generate_stieltjes(dist, len(nodes)-1, retall=True)[0]
poly = chaospy.poly.flatten(chaospy.poly.Poly(poly))
weights_inverse = poly(nodes)
weights = numpy.linalg.inv(weights_inverse)
return weights[:, 0] | def create_weights(nodes, dist) | Create weights for the Laja method. | 5.279099 | 5.383077 | 0.980684 |
if not scipy.sparse.issparse(mat):
mat = numpy.asfarray(mat)
assert numpy.allclose(mat, mat.T)
size = mat.shape[0]
mat_diag = mat.diagonal()
gamma = abs(mat_diag).max()
off_diag = abs(mat - numpy.diag(mat_diag)).max()
delta = eps*max(gamma + off_diag, 1)
beta = numpy.sqrt(max(gamma, off_diag/size, eps))
lowtri = _gill_king(mat, beta, delta)
return lowtri | def gill_king(mat, eps=1e-16) | Gill-King algorithm for modified cholesky decomposition.
Args:
mat (numpy.ndarray):
Must be a non-singular and symmetric matrix. If sparse, the result
will also be sparse.
eps (float):
Error tolerance used in algorithm.
Returns:
(numpy.ndarray):
Lower triangular Cholesky factor.
Examples:
>>> mat = [[4, 2, 1], [2, 6, 3], [1, 3, -.004]]
>>> lowtri = gill_king(mat)
>>> print(numpy.around(lowtri, 4))
[[2. 0. 0. ]
[1. 2.2361 0. ]
[0.5 1.118 1.2264]]
>>> print(numpy.around(numpy.dot(lowtri, lowtri.T), 4))
[[4. 2. 1. ]
[2. 6. 3. ]
[1. 3. 3.004]] | 4.01831 | 4.075337 | 0.986007 |
size = mat.shape[0]
# initialize d_vec and lowtri
if scipy.sparse.issparse(mat):
lowtri = scipy.sparse.eye(*mat.shape)
else:
lowtri = numpy.eye(size)
d_vec = numpy.zeros(size, dtype=float)
# there are no inner for loops, everything implemented with
# vector operations for a reasonable level of efficiency
for idx in range(size):
if idx == 0:
idz = [] # column index: all columns to left of diagonal
# d_vec(idz) doesn't work in case idz is empty
else:
idz = numpy.s_[:idx]
djtemp = mat[idx, idx] - numpy.dot(
lowtri[idx, idz], d_vec[idz]*lowtri[idx, idz].T)
# C(idx, idx) in book
if idx < size - 1:
idy = numpy.s_[idx+1:size]
# row index: all rows below diagonal
ccol = mat[idy, idx] - numpy.dot(
lowtri[idy, idz], d_vec[idz]*lowtri[idx, idz].T)
# C(idy, idx) in book
theta = abs(ccol).max()
# guarantees d_vec(idx) not too small and lowtri(idy, idx) not too
# big in sufficiently positive definite case, d_vec(idx) = djtemp
d_vec[idx] = max(abs(djtemp), (theta/beta)**2, delta)
lowtri[idy, idx] = ccol/d_vec[idx]
else:
d_vec[idx] = max(abs(djtemp), delta)
# convert to usual output format: replace lowtri by lowtri*sqrt(D) and
# transpose
for idx in range(size):
lowtri[:, idx] = lowtri[:, idx]*numpy.sqrt(d_vec[idx])
# lowtri = lowtri*diag(sqrt(d_vec)) bad in sparse case
return lowtri | def _gill_king(mat, beta, delta) | Backend function for the Gill-King algorithm. | 4.82156 | 4.814476 | 1.001471 |
random_state = numpy.random.get_state()
numpy.random.seed(seed)
forward = partial(evaluation.evaluate_forward, cache=cache,
distribution=distribution, parameters=parameters)
dim = len(distribution)
upper = numpy.ones((dim, 1))
for _ in range(100):
indices = forward(x_data=upper) < 1
if not numpy.any(indices):
break
upper[indices] *= 2
lower = -numpy.ones((dim, 1))
for _ in range(100):
indices = forward(x_data=lower) > 0
if not numpy.any(indices):
break
lower[indices] *= 2
for _ in range(iterations):
rand = numpy.random.random(dim)
proposal = (rand*lower.T + (1-rand)*upper.T).T
evals = forward(x_data=proposal)
indices0 = evals > 0
indices1 = evals < 1
range_ = numpy.random.choice(dim, size=dim, replace=False)
upper_ = numpy.where(indices1, upper, evals)
for idx in range_:
if upper.flatten()[idx] == upper_.flatten()[idx]:
continue
if numpy.all(forward(x_data=upper_) == 1):
upper = upper_
break
upper_[idx] = upper[idx]
lower_ = numpy.where(indices0, lower, evals)
for idx in range_:
if lower.flatten()[idx] == lower_.flatten()[idx]:
continue
if numpy.all(forward(x_data=lower_) == 0):
lower = lower_
break
lower_[idx] = lower[idx]
if numpy.all(indices0 & indices1):
break
else:
if retall:
return proposal, lower, upper
return proposal
raise evaluation.DependencyError(
"Too many iterations required to find interior point.")
numpy.random.set_state(random_state)
if retall:
return proposal, lower, upper
return proposal | def find_interior_point(
distribution,
parameters=None,
cache=None,
iterations=1000,
retall=False,
seed=None,
) | Find interior point of the distribution where forward evaluation is
guarantied to be both ``distribution.fwd(xloc) > 0`` and
``distribution.fwd(xloc) < 1``.
Args:
distribution (Dist): Distribution to find interior on.
parameters (Optional[Dict[Dist, numpy.ndarray]]): Parameters for the
distribution.
cache (Optional[Dict[Dist, numpy.ndarray]]): Memory cache for the
location in the evaluation so far.
iterations (int): The number of iterations allowed to be performed
retall (bool): If provided, lower and upper bound which guaranties that
``distribution.fwd(lower) == 0`` and
``distribution.fwd(upper) == 1`` is returned as well.
seed (Optional[int]): Fix random seed.
Returns:
numpy.ndarray: An input array with shape ``(len(distribution),)`` which
is guarantied to be on the interior of the probability distribution.
Example:
>>> distribution = chaospy.MvNormal([1, 2, 3], numpy.eye(3)+.03)
>>> midpoint, lower, upper = find_interior_point(
... distribution, retall=True, seed=1234)
>>> print(lower.T)
[[-64. -64. -64.]]
>>> print(numpy.around(midpoint, 4).T)
[[ 0.6784 -33.7687 -19.0182]]
>>> print(upper.T)
[[16. 16. 16.]]
>>> distribution = chaospy.Uniform(1000, 1010)
>>> midpoint, lower, upper = find_interior_point(
... distribution, retall=True, seed=1234)
>>> print(numpy.around(lower, 4))
[[-1.]]
>>> print(numpy.around(midpoint, 4))
[[1009.8873]]
>>> print(numpy.around(upper, 4))
[[1024.]] | 2.581609 | 2.690463 | 0.959541 |
dim = len(dist)
shape = K.shape
size = int(K.size/dim)
K = K.reshape(dim, size)
if dim > 1:
shape = shape[1:]
X, W = quad.generate_quadrature(order, dist, rule=rule, normalize=True, **kws)
grid = numpy.mgrid[:len(X[0]), :size]
X = X.T[grid[0]].T
K = K.T[grid[1]].T
out = numpy.prod(X**K, 0)*W
if control_var is not None:
Y = control_var.ppf(dist.fwd(X))
mu = control_var.mom(numpy.eye(len(control_var)))
if (mu.size == 1) and (dim > 1):
mu = mu.repeat(dim)
for d in range(dim):
alpha = numpy.cov(out, Y[d])[0, 1]/numpy.var(Y[d])
out -= alpha*(Y[d]-mu)
out = numpy.sum(out, -1)
return out | def approximate_moment(
dist,
K,
retall=False,
control_var=None,
rule="F",
order=1000,
**kws
) | Approximation method for estimation of raw statistical moments.
Args:
dist : Dist
Distribution domain with dim=len(dist)
K : numpy.ndarray
The exponents of the moments of interest with shape (dim,K).
control_var : Dist
If provided will be used as a control variable to try to reduce
the error.
acc (:py:data:typing.Optional[int]):
The order of quadrature/MCI
sparse : bool
If True used Smolyak's sparse grid instead of normal tensor
product grid in numerical integration.
rule : str
Quadrature rule
Key Description
---- -----------
"G" Optiomal Gaussian quadrature from Golub-Welsch
Slow for high order and composit is ignored.
"E" Gauss-Legendre quadrature
"C" Clenshaw-Curtis quadrature. Exponential growth rule is
used when sparse is True to make the rule nested.
Monte Carlo Integration
Key Description
---- -----------
"H" Halton sequence
"K" Korobov set
"L" Latin hypercube sampling
"M" Hammersley sequence
"R" (Pseudo-)Random sampling
"S" Sobol sequence
composite (:py:data:typing.Optional[int, numpy.ndarray]):
If provided, composite quadrature will be used.
Ignored in the case if gaussian=True.
If int provided, determines number of even domain splits
If array of ints, determines number of even domain splits along
each axis
If array of arrays/floats, determines location of splits
antithetic (:py:data:typing.Optional[numpy.ndarray]):
List of bool. Represents the axes to mirror using antithetic
variable during MCI. | 4.123574 | 4.03844 | 1.021081 |
if parameters is None:
parameters = dist.prm.copy()
if cache is None:
cache = {}
xloc = numpy.asfarray(xloc)
lo, up = numpy.min(xloc), numpy.max(xloc)
mu = .5*(lo+up)
eps = numpy.where(xloc < mu, eps, -eps)*xloc
floc = evaluation.evaluate_forward(
dist, xloc, parameters=parameters.copy(), cache=cache.copy())
for d in range(len(dist)):
xloc[d] += eps[d]
tmp = evaluation.evaluate_forward(
dist, xloc, parameters=parameters.copy(), cache=cache.copy())
floc[d] -= tmp[d]
xloc[d] -= eps[d]
floc = numpy.abs(floc / eps)
return floc | def approximate_density(
dist,
xloc,
parameters=None,
cache=None,
eps=1.e-7
) | Approximate the probability density function.
Args:
dist : Dist
Distribution in question. May not be an advanced variable.
xloc : numpy.ndarray
Location coordinates. Requires that xloc.shape=(len(dist), K).
eps : float
Acceptable error level for the approximations
retall : bool
If True return Graph with the next calculation state with the
approximation.
Returns:
numpy.ndarray: Local probability density function with
``out.shape == xloc.shape``. To calculate actual density function,
evaluate ``numpy.prod(out, 0)``.
Example:
>>> distribution = chaospy.Normal(1000, 10)
>>> xloc = numpy.array([[990, 1000, 1010]])
>>> print(numpy.around(approximate_density(distribution, xloc), 4))
[[0.0242 0.0399 0.0242]]
>>> print(numpy.around(distribution.pdf(xloc), 4))
[[0.0242 0.0399 0.0242]] | 2.804732 | 3.227944 | 0.868891 |
assert number_base > 1
idx = numpy.asarray(idx).flatten() + 1
out = numpy.zeros(len(idx), dtype=float)
base = float(number_base)
active = numpy.ones(len(idx), dtype=bool)
while numpy.any(active):
out[active] += (idx[active] % number_base)/base
idx //= number_base
base *= number_base
active = idx > 0
return out | def create_van_der_corput_samples(idx, number_base=2) | Van der Corput samples.
Args:
idx (int, numpy.ndarray):
The index of the sequence. If array is provided, all values in
array is returned.
number_base (int):
The numerical base from where to create the samples from.
Returns (float, numpy.ndarray):
Van der Corput samples. | 3.379241 | 3.658727 | 0.923611 |
if len(args) > 2:
return add(args[0], add(args[1], args[1:]))
if len(args) == 1:
return args[0]
part1, part2 = args
if isinstance(part2, Poly):
if part2.dim > part1.dim:
part1 = chaospy.dimension.setdim(part1, part2.dim)
elif part2.dim < part1.dim:
part2 = chaospy.dimension.setdim(part2, part1.dim)
dtype = chaospy.poly.typing.dtyping(part1.dtype, part2.dtype)
core1 = part1.A.copy()
core2 = part2.A.copy()
if np.prod(part2.shape) > np.prod(part1.shape):
shape = part2.shape
ones = np.ones(shape, dtype=int)
for key in core1:
core1[key] = core1[key]*ones
else:
shape = part1.shape
ones = np.ones(shape, dtype=int)
for key in core2:
core2[key] = core2[key]*ones
for idx in core1:
if idx in core2:
core2[idx] = core2[idx] + core1[idx]
else:
core2[idx] = core1[idx]
out = core2
return Poly(out, part1.dim, shape, dtype)
part2 = np.asarray(part2)
core = part1.A.copy()
dtype = chaospy.poly.typing.dtyping(part1.dtype, part2.dtype)
zero = (0,)*part1.dim
if zero not in core:
core[zero] = np.zeros(part1.shape, dtype=int)
core[zero] = core[zero] + part2
if np.prod(part2.shape) > np.prod(part1.shape):
ones = np.ones(part2.shape, dtype=dtype)
for key in core:
core[key] = core[key]*ones
return Poly(core, part1.dim, None, dtype) | def add(*args) | Polynomial addition. | 2.23145 | 2.16917 | 1.028711 |
if len(args) > 2:
return add(args[0], add(args[1], args[1:]))
if len(args) == 1:
return args[0]
part1, part2 = args
if not isinstance(part2, Poly):
if isinstance(part2, (float, int)):
part2 = np.asarray(part2)
if not part2.shape:
core = part1.A.copy()
dtype = chaospy.poly.typing.dtyping(
part1.dtype, part2.dtype)
for key in part1.keys:
core[key] = np.asarray(core[key]*part2, dtype)
return Poly(core, part1.dim, part1.shape, dtype)
part2 = Poly(part2)
if part2.dim > part1.dim:
part1 = chaospy.dimension.setdim(part1, part2.dim)
elif part2.dim < part1.dim:
part2 = chaospy.dimension.setdim(part2, part1.dim)
if np.prod(part1.shape) >= np.prod(part2.shape):
shape = part1.shape
else:
shape = part2.shape
dtype = chaospy.poly.typing.dtyping(part1.dtype, part2.dtype)
if part1.dtype != part2.dtype:
if part1.dtype == dtype:
part2 = chaospy.poly.typing.asfloat(part2)
else:
part1 = chaospy.poly.typing.asfloat(part1)
core = {}
for idx1 in part2.A:
for idx2 in part1.A:
key = tuple(np.array(idx1) + np.array(idx2))
core[key] = np.asarray(
core.get(key, 0) + part2.A[idx1]*part1.A[idx2])
core = {key: value for key, value in core.items() if np.any(value)}
out = Poly(core, part1.dim, shape, dtype)
return out | def mul(*args) | Polynomial multiplication. | 2.389755 | 2.35039 | 1.016748 |
if self.eps == 0:
return [xmin, center, xmax], [0, 0, xmax]
else:
n = float(resolution_inside)/self.eps
x = np.concatenate((
np.linspace(xmin, center-self.eps, resolution_outside+1),
np.linspace(center-self.eps, center+self.eps, n+1),
np.linspace(center+self.eps, xmax, resolution_outside+1)))
y = self(x)
return x, y | def plot(self, xmin=-1, xmax=1, center=0,
resolution_outside=20, resolution_inside=200) | Return arrays x, y for plotting the Heaviside function
H(x-`center`) on [`xmin`, `xmax`]. For the exact
Heaviside function,
``x = [xmin, center, xmax]; y = [0, 0, 1]``,
while for the smoothed version, the ``x`` array
is computed on basis of the `eps` parameter, with
`resolution_outside` intervals on each side of the smoothed
region and `resolution_inside` intervals in the smoothed region. | 2.648593 | 2.383379 | 1.111277 |
if xmin > self.L or xmax < self.R:
raise ValueError('xmin=%g > L=%g or xmax=%g < R=%g is meaningless for plot' % (xmin, self.L, xmax, self.R))
if self.eps_L == 0 and self.eps_R == 0:
return ([xmin, self.L, self.L, self.R, self.R, xmax],
[0, 0, 1, 1, 0, 0])
else:
n = float(resolution_inside)/(0.5*(self.eps_L + self.eps_R))
x = np.concatenate((
np.linspace(xmin, self.L-self.eps_L, resolution_outside+1),
np.linspace(self.L-self.eps_L, self.R+self.eps_R,
resolution_inside+1),
np.linspace(self.R+self.eps_R, xmax, resolution_outside+1)))
y = self(x)
return x, y | def plot(self, xmin=-1, xmax=1,
resolution_outside=20, resolution_inside=200) | Return arrays x, y for plotting IndicatorFunction
on [`xmin`, `xmax`]. For the exact discontinuous
indicator function, we typically have
``x = [xmin, L, L, R, R, xmax]; y = [0, 0, 1, 1, 0, 0]``,
while for the smoothed version, the densities of
coordinates in the ``x`` array is computed on basis of the
`eps` parameter with `resolution_outside` plotting intervals
outside the smoothed regions and `resolution_inside` intervals
inside the smoothed regions. | 2.367666 | 2.128472 | 1.112378 |
if self.eps == 0:
x = []; y = []
for I, value in zip(self._indicator_functions, self._values):
x.append(I.L)
y.append(value)
x.append(I.R)
y.append(value)
return x, y
else:
n = float(resolution_smooth_regions)/self.eps
if len(self.data) == 1:
return [self.L, self.R], [self._values[0], self._values[0]]
else:
x = [np.linspace(self.data[0][0], self.data[1][0]-self.eps,
resolution_constant_regions+1)]
# Iterate over all internal discontinuities
for I in self._indicator_functions[1:]:
x.append(np.linspace(I.L-self.eps, I.L+self.eps,
resolution_smooth_regions+1))
x.append(np.linspace(I.L+self.eps, I.R-self.eps,
resolution_constant_regions+1))
# Last part
x.append(np.linspace(I.R-self.eps, I.R, 3))
x = np.concatenate(x)
y = self(x)
return x, y | def plot(self,
resolution_constant_regions=20,
resolution_smooth_regions=200) | Return arrays x, y for plotting the piecewise constant function.
Just the minimum number of straight lines are returned if
``eps=0``, otherwise `resolution_constant_regions` plotting intervals
are insed in the constant regions with `resolution_smooth_regions`
plotting intervals in the smoothed regions. | 2.725188 | 2.528022 | 1.077992 |
poly = Poly(poly)
diffvar = Poly(diffvar)
if not chaospy.poly.caller.is_decomposed(diffvar):
sum(differential(poly, chaospy.poly.caller.decompose(diffvar)))
if diffvar.shape:
return Poly([differential(poly, pol) for pol in diffvar])
if diffvar.dim > poly.dim:
poly = chaospy.poly.dimension.setdim(poly, diffvar.dim)
else:
diffvar = chaospy.poly.dimension.setdim(diffvar, poly.dim)
qkey = diffvar.keys[0]
core = {}
for key in poly.keys:
newkey = np.array(key) - np.array(qkey)
if np.any(newkey < 0):
continue
newkey = tuple(newkey)
core[newkey] = poly.A[key] * np.prod(
[fac(key[idx], exact=True) / fac(newkey[idx], exact=True)
for idx in range(poly.dim)])
return Poly(core, poly.dim, poly.shape, poly.dtype) | def differential(poly, diffvar) | Polynomial differential operator.
Args:
poly (Poly) : Polynomial to be differentiated.
diffvar (Poly) : Polynomial to differentiate by. Must be decomposed. If
polynomial array, the output is the Jacobian matrix.
Examples:
>>> q0, q1 = chaospy.variable(2)
>>> poly = chaospy.Poly([1, q0, q0*q1**2+1])
>>> print(poly)
[1, q0, q0q1^2+1]
>>> print(differential(poly, q0))
[0, 1, q1^2]
>>> print(differential(poly, q1))
[0, 0, 2q0q1] | 3.685789 | 3.64904 | 1.010071 |
return differential(poly, chaospy.poly.collection.basis(1, 1, poly.dim)) | def gradient(poly) | Gradient of a polynomial.
Args:
poly (Poly) : polynomial to take gradient of.
Returns:
(Poly) : The resulting gradient.
Examples:
>>> q0, q1, q2 = chaospy.variable(3)
>>> poly = 2*q0 + q1*q2
>>> print(chaospy.gradient(poly))
[2, q2, q1] | 20.786161 | 30.576591 | 0.679806 |
left = evaluation.get_forward_cache(left, cache)
right = evaluation.get_forward_cache(right, cache)
if isinstance(left, Dist):
if isinstance(right, Dist):
raise StochasticallyDependentError(
"under-defined distribution {} or {}".format(left, right))
elif not isinstance(right, Dist):
return left**right, left**right
else:
output = numpy.ones(xloc.shape)
left = left * output
assert numpy.all(left >= 0), "root of negative number"
indices = xloc > 0
output[indices] = numpy.log(xloc[indices])
output[~indices] = -numpy.inf
indices = left != 1
output[indices] /= numpy.log(left[indices])
output = evaluation.evaluate_bound(right, output, cache=cache)
output = left**output
output[:] = (
numpy.where(output[0] < output[1], output[0], output[1]),
numpy.where(output[0] < output[1], output[1], output[0]),
)
return output
output = numpy.zeros(xloc.shape)
right = right + output
indices = right > 0
output[indices] = numpy.abs(xloc[indices])**(1/right[indices])
output[indices] *= numpy.sign(xloc[indices])
output[right == 0] = 1
output[(xloc == 0) & (right < 0)] = numpy.inf
output = evaluation.evaluate_bound(left, output, cache=cache)
pair = right % 2 == 0
bnd_ = numpy.empty(output.shape)
bnd_[0] = numpy.where(pair*(output[0]*output[1] < 0), 0, output[0])
bnd_[0] = numpy.where(pair*(output[0]*output[1] > 0), \
numpy.min(numpy.abs(output), 0), bnd_[0])**right
bnd_[1] = numpy.where(pair, numpy.max(numpy.abs(output), 0),
output[1])**right
bnd_[0], bnd_[1] = (
numpy.where(bnd_[0] < bnd_[1], bnd_[0], bnd_[1]),
numpy.where(bnd_[0] < bnd_[1], bnd_[1], bnd_[0]),
)
return bnd_ | def _bnd(self, xloc, left, right, cache) | Distribution bounds.
Example:
>>> print(chaospy.Uniform().range([-2, 0, 2, 4]))
[[0. 0. 0. 0.]
[1. 1. 1. 1.]]
>>> print(chaospy.Pow(chaospy.Uniform(), 2).range([-2, 0, 2, 4]))
[[0. 0. 0. 0.]
[1. 1. 1. 1.]]
>>> print(chaospy.Pow(chaospy.Uniform(1, 2), -1).range([-2, 0, 2, 4]))
[[0.5 0.5 0.5 0.5]
[1. 1. 1. 1. ]]
>>> print(chaospy.Pow(2, chaospy.Uniform()).range([-2, 0, 2, 4]))
[[1. 1. 1. 1.]
[2. 2. 2. 2.]]
>>> print(chaospy.Pow(2, chaospy.Uniform(-1, 0)).range([-2, 0, 2, 4]))
[[0.5 0.5 0.5 0.5]
[1. 1. 1. 1. ]]
>>> print(chaospy.Pow(2, 3).range([-2, 0, 2, 4]))
[[8. 8. 8. 8.]
[8. 8. 8. 8.]] | 2.671868 | 2.72842 | 0.979273 |
left = evaluation.get_forward_cache(left, cache)
right = evaluation.get_forward_cache(right, cache)
if isinstance(left, Dist):
if isinstance(right, Dist):
raise StochasticallyDependentError(
"under-defined distribution {} or {}".format(left, right))
elif not isinstance(right, Dist):
return numpy.inf
else:
assert numpy.all(left > 0), "imaginary result"
y = (numpy.log(numpy.abs(xloc) + 1.*(xloc <= 0)) /
numpy.log(numpy.abs(left)+1.*(left == 1)))
out = evaluation.evaluate_forward(right, y)
out = numpy.where(xloc <= 0, 0., out)
return out
y = numpy.sign(xloc)*numpy.abs(xloc)**(1./right)
pairs = numpy.sign(xloc**right) != -1
out1, out2 = (
evaluation.evaluate_forward(left, y, cache=cache),
evaluation.evaluate_forward(left, -y, cache=cache),
)
out = numpy.where(right < 0, 1-out1, out1-pairs*out2)
return out | def _cdf(self, xloc, left, right, cache) | Cumulative distribution function.
Example:
>>> print(chaospy.Uniform().fwd([-0.5, 0.5, 1.5, 2.5]))
[0. 0.5 1. 1. ]
>>> print(chaospy.Pow(chaospy.Uniform(), 2).fwd([-0.5, 0.5, 1.5, 2.5]))
[0. 0.70710678 1. 1. ]
>>> print(chaospy.Pow(chaospy.Uniform(1, 2), -1).fwd([0.4, 0.6, 0.8, 1.2]))
[0. 0.33333333 0.75 1. ]
>>> print(chaospy.Pow(2, chaospy.Uniform()).fwd([-0.5, 0.5, 1.5, 2.5]))
[0. 0. 0.5849625 1. ]
>>> print(chaospy.Pow(2, chaospy.Uniform(-1, 0)).fwd([0.4, 0.6, 0.8, 1.2]))
[0. 0.26303441 0.67807191 1. ]
>>> print(chaospy.Pow(2, 3).fwd([7, 8, 9]))
[0. 1. 1.] | 4.120614 | 4.318824 | 0.954106 |
left = evaluation.get_inverse_cache(left, cache)
right = evaluation.get_inverse_cache(right, cache)
if isinstance(left, Dist):
if isinstance(right, Dist):
raise StochasticallyDependentError(
"under-defined distribution {} or {}".format(left, right))
elif not isinstance(right, Dist):
return left**right
else:
out = evaluation.evaluate_inverse(right, q, cache=cache)
out = numpy.where(left < 0, 1-out, out)
out = left**out
return out
right = right + numpy.zeros(q.shape)
q = numpy.where(right < 0, 1-q, q)
out = evaluation.evaluate_inverse(left, q, cache=cache)**right
return out | def _ppf(self, q, left, right, cache) | Point percentile function.
Example:
>>> print(chaospy.Uniform().inv([0.1, 0.2, 0.9]))
[0.1 0.2 0.9]
>>> print(chaospy.Pow(chaospy.Uniform(), 2).inv([0.1, 0.2, 0.9]))
[0.01 0.04 0.81]
>>> print(chaospy.Pow(chaospy.Uniform(1, 2), -1).inv([0.1, 0.2, 0.9]))
[0.52631579 0.55555556 0.90909091]
>>> print(chaospy.Pow(2, chaospy.Uniform()).inv([0.1, 0.2, 0.9]))
[1.07177346 1.14869835 1.86606598]
>>> print(chaospy.Pow(2, chaospy.Uniform(-1, 0)).inv([0.1, 0.2, 0.9]))
[0.53588673 0.57434918 0.93303299]
>>> print(chaospy.Pow(2, 3).inv([0.1, 0.2, 0.9]))
[8. 8. 8.] | 3.688947 | 3.934699 | 0.937542 |
left = evaluation.get_forward_cache(left, cache)
right = evaluation.get_forward_cache(right, cache)
if isinstance(left, Dist):
if isinstance(right, Dist):
raise StochasticallyDependentError(
"under-defined distribution {} or {}".format(left, right))
elif not isinstance(right, Dist):
return numpy.inf
else:
assert numpy.all(left > 0), "imaginary result"
x_ = numpy.where(xloc <= 0, -numpy.inf,
numpy.log(xloc + 1.*(xloc<=0))/numpy.log(left+1.*(left == 1)))
num_ = numpy.log(left+1.*(left == 1))*xloc
num_ = num_ + 1.*(num_==0)
out = evaluation.evaluate_density(right, x_, cache=cache)/num_
return out
x_ = numpy.sign(xloc)*numpy.abs(xloc)**(1./right -1)
xloc = numpy.sign(xloc)*numpy.abs(xloc)**(1./right)
pairs = numpy.sign(xloc**right) == 1
out = evaluation.evaluate_density(left, xloc, cache=cache)
if numpy.any(pairs):
out = out + pairs*evaluation.evaluate_density(left, -xloc, cache=cache)
out = numpy.sign(right)*out * x_ / right
out[numpy.isnan(out)] = numpy.inf
return out | def _pdf(self, xloc, left, right, cache) | Probability density function.
Example:
>>> print(chaospy.Uniform().pdf([-0.5, 0.5, 1.5, 2.5]))
[0. 1. 0. 0.]
>>> print(chaospy.Pow(chaospy.Uniform(), 2).pdf([-0.5, 0.5, 1.5, 2.5]))
[0. 0.70710678 0. 0. ]
>>> print(chaospy.Pow(chaospy.Uniform(1, 2), -1).pdf([0.4, 0.6, 0.8, 1.2]))
[0. 2.77777778 1.5625 0. ]
>>> print(chaospy.Pow(2, chaospy.Uniform()).pdf([-0.5, 0.5, 1.5, 2.5]))
[0. 0. 0.96179669 0. ]
>>> print(chaospy.Pow(2, chaospy.Uniform(-1, 0)).pdf([0.4, 0.6, 0.8, 1.2]))
[0. 2.40449173 1.8033688 0. ]
>>> print(chaospy.Pow(2, 3).pdf([7, 8, 9]))
[ 0. inf 0.] | 4.009871 | 4.158485 | 0.964262 |
if isinstance(right, Dist):
raise StochasticallyDependentError(
"distribution as exponent not supported.")
if not isinstance(left, Dist):
return left**(right*k)
if numpy.any(right < 0):
raise StochasticallyDependentError(
"distribution to negative power not supported.")
if not numpy.allclose(right, numpy.array(right, dtype=int)):
raise StochasticallyDependentError(
"distribution to fractional power not supported.")
return evaluation.evaluate_moment(left, k*right, cache=cache) | def _mom(self, k, left, right, cache) | Statistical moments.
Example:
>>> print(numpy.around(chaospy.Uniform().mom([0, 1, 2, 3]), 4))
[1. 0.5 0.3333 0.25 ]
>>> print(numpy.around(chaospy.Pow(chaospy.Uniform(), 2).mom([0, 1, 2, 3]), 4))
[1. 0.3333 0.2 0.1429]
>>> print(numpy.around(chaospy.Pow(chaospy.Uniform(1, 2), -1).mom([0, 1, 2, 3]), 4))
[1. 0.6931 0.5 0.375 ]
>>> print(numpy.around(chaospy.Pow(2, chaospy.Uniform()).mom([0, 1, 2, 3]), 4))
[1. 1.4427 2.164 3.3663]
>>> print(numpy.around(chaospy.Pow(2, chaospy.Uniform(-1, 0)).mom([0, 1, 2, 3]), 4))
[1. 0.7213 0.541 0.4208]
>>> print(numpy.around(chaospy.Pow(2, 1).mom([0, 1, 2, 3]), 4))
[1. 2. 4. 8.] | 4.560004 | 4.315637 | 1.056624 |
assert len(k_data) == len(distribution), (
"distribution %s is not of length %d" % (distribution, len(k_data)))
assert len(k_data.shape) == 1
def cache_key(distribution):
return (tuple(k_data), distribution)
if cache is None:
cache = {}
else:
if cache_key(distribution) in cache:
return cache[cache_key(distribution)]
try:
parameters = load_parameters(
distribution, "_ttr", parameters, cache, cache_key)
coeff1, coeff2 = distribution._ttr(k_data, **parameters)
except NotImplementedError:
from ... import quad
_, _, coeff1, coeff2 = quad.stieltjes._stieltjes_approx(
distribution, order=numpy.max(k_data), accuracy=100, normed=False)
range_ = numpy.arange(len(distribution), dtype=int)
coeff1 = coeff1[range_, k_data]
coeff2 = coeff2[range_, k_data]
out = numpy.zeros((2,) + k_data.shape)
out.T[:, 0] = numpy.asarray(coeff1).T
out.T[:, 1] = numpy.asarray(coeff2).T
if len(distribution) == 1:
out = out[:, 0]
return out | def evaluate_recurrence_coefficients(
distribution,
k_data,
parameters=None,
cache=None,
) | Evaluate three terms recurrence coefficients (TTR).
Args:
distribution (Dist):
Distribution to evaluate.
x_data (numpy.ndarray):
Locations for where evaluate recurrence coefficients for.
parameters (:py:data:typing.Any):
Collection of parameters to override the default ones in the
distribution.
cache (:py:data:typing.Any):
A collection of previous calculations in case the same distribution
turns up on more than one occasion.
Returns:
The recurrence coefficients ``A`` and ``B`` of ``distribution`` at
location ``x_data`` using parameters ``parameters``. | 3.397789 | 3.266083 | 1.040325 |
values = numpy.empty(dim)
values[0] = 1
for idx in range(1, dim):
values[idx] = base*values[idx-1] % (order+1)
grid = numpy.mgrid[:dim, :order+1]
out = values[grid[0]] * (grid[1]+1) / (order+1.) % 1.
return out[:, :order] | def create_korobov_samples(order, dim, base=17797) | Create Korobov lattice samples.
Args:
order (int):
The order of the Korobov latice. Defines the number of
samples.
dim (int):
The number of dimensions in the output.
base (int):
The number based used to calculate the distribution of values.
Returns (numpy.ndarray):
Korobov lattice with ``shape == (dim, order)`` | 3.998649 | 4.228079 | 0.945737 |
return evaluation.evaluate_forward(dist, numpy.e**xloc, cache=cache) | def _cdf(self, xloc, dist, cache) | Cumulative distribution function. | 15.80227 | 12.797116 | 1.234831 |
return numpy.log(evaluation.evaluate_bound(
dist, numpy.e**xloc, cache=cache)) | def _bnd(self, xloc, dist, cache) | Distribution bounds. | 14.761956 | 14.341515 | 1.029316 |
numpy.random.seed(1000)
def foo(coord, param):
return param[0] * numpy.e ** (-param[1] * coord)
coord = numpy.linspace(0, 10, 200)
distribution = cp.J(cp.Uniform(1, 2), cp.Uniform(0.1, 0.2))
samples = distribution.sample(50)
evals = numpy.array([foo(coord, sample) for sample in samples.T])
plt.plot(coord, evals.T, "k-", lw=3, alpha=0.2)
plt.xlabel(r"\verb;coord;")
plt.ylabel(r"function evaluations \verb;foo;")
plt.savefig("demonstration.png")
plt.clf()
samples = distribution.sample(1000, "H")
evals = [foo(coord, sample) for sample in samples.T]
expected = numpy.mean(evals, 0)
deviation = numpy.std(evals, 0)
plt.fill_between(
coord, expected-deviation, expected+deviation,
color="k", alpha=0.3
)
plt.plot(coord, expected, "k--", lw=3)
plt.xlabel(r"\verb;coord;")
plt.ylabel(r"function evaluations \verb;foo;")
plt.title("Results using Monte Carlo simulation")
plt.savefig("results_montecarlo.png")
plt.clf()
polynomial_expansion = cp.orth_ttr(8, distribution)
foo_approx = cp.fit_regression(polynomial_expansion, samples, evals)
expected = cp.E(foo_approx, distribution)
deviation = cp.Std(foo_approx, distribution)
plt.fill_between(
coord, expected-deviation, expected+deviation,
color="k", alpha=0.3
)
plt.plot(coord, expected, "k--", lw=3)
plt.xlabel(r"\verb;coord;")
plt.ylabel(r"function evaluations \verb;foo;")
plt.title("Results using point collocation method")
plt.savefig("results_collocation.png")
plt.clf()
absissas, weights = cp.generate_quadrature(8, distribution, "C")
evals = [foo(coord, val) for val in absissas.T]
foo_approx = cp.fit_quadrature(polynomial_expansion, absissas, weights, evals)
expected = cp.E(foo_approx, distribution)
deviation = cp.Std(foo_approx, distribution)
plt.fill_between(
coord, expected-deviation, expected+deviation,
color="k", alpha=0.3
)
plt.plot(coord, expected, "k--", lw=3)
plt.xlabel(r"\verb;coord;")
plt.ylabel(r"function evaluations \verb;foo;")
plt.title("Results using psuedo-spectral projection method")
plt.savefig("results_spectral.png")
plt.clf() | def plot_figures() | Plot figures for tutorial. | 2.43712 | 2.422279 | 1.006127 |
assert isinstance(rule, int)
if len(dist) > 1:
if isinstance(order, int):
values = [quad_genz_keister(order, d, rule) for d in dist]
else:
values = [quad_genz_keister(order[i], dist[i], rule)
for i in range(len(dist))]
abscissas = [_[0][0] for _ in values]
abscissas = chaospy.quad.combine(abscissas).T
weights = [_[1] for _ in values]
weights = np.prod(chaospy.quad.combine(weights), -1)
return abscissas, weights
foo = chaospy.quad.genz_keister.COLLECTION[rule]
abscissas, weights = foo(order)
abscissas = dist.inv(scipy.special.ndtr(abscissas))
abscissas = abscissas.reshape(1, abscissas.size)
return abscissas, weights | def quad_genz_keister(order, dist, rule=24) | Genz-Keister quadrature rule.
Eabsicassample:
>>> abscissas, weights = quad_genz_keister(
... order=1, dist=chaospy.Uniform(0, 1))
>>> print(numpy.around(abscissas, 4))
[[0.0416 0.5 0.9584]]
>>> print(numpy.around(weights, 4))
[0.1667 0.6667 0.1667] | 2.777441 | 2.779853 | 0.999132 |
shape = poly.shape
poly = polynomials.flatten(poly)
q = numpy.array(q)/100.
dim = len(dist)
# Interior
Z = dist.sample(sample, **kws)
if dim==1:
Z = (Z, )
q = numpy.array([q])
poly1 = poly(*Z)
# Min/max
mi, ma = dist.range().reshape(2, dim)
ext = numpy.mgrid[(slice(0, 2, 1), )*dim].reshape(dim, 2**dim).T
ext = numpy.where(ext, mi, ma).T
poly2 = poly(*ext)
poly2 = numpy.array([_ for _ in poly2.T if not numpy.any(numpy.isnan(_))]).T
# Finish
if poly2.shape:
poly1 = numpy.concatenate([poly1, poly2], -1)
samples = poly1.shape[-1]
poly1.sort()
out = poly1.T[numpy.asarray(q*(samples-1), dtype=int)]
out = out.reshape(q.shape + shape)
return out | def Perc(poly, q, dist, sample=10000, **kws) | Percentile function.
Note that this function is an empirical function that operates using Monte
Carlo sampling.
Args:
poly (Poly):
Polynomial of interest.
q (numpy.ndarray):
positions where percentiles are taken. Must be a number or an
array, where all values are on the interval ``[0, 100]``.
dist (Dist):
Defines the space where percentile is taken.
sample (int):
Number of samples used in estimation.
Returns:
(numpy.ndarray):
Percentiles of ``poly`` with ``Q.shape=poly.shape+q.shape``.
Examples:
>>> dist = chaospy.J(chaospy.Gamma(1, 1), chaospy.Normal(0, 2))
>>> x, y = chaospy.variable(2)
>>> poly = chaospy.Poly([0.05*x, 0.2*y, 0.01*x*y])
>>> print(numpy.around(chaospy.Perc(poly, [0, 5, 50, 95, 100], dist), 2))
[[ 0. -3. -6.3 ]
[ 0. -0.64 -0.04]
[ 0.03 -0.01 -0. ]
[ 0.15 0.66 0.04]
[ 2.1 3. 6.3 ]] | 4.790602 | 5.190289 | 0.922993 |
abscissas, weights = chaospy.quad.collection.golub_welsch(order, dist)
likelihood = dist.pdf(abscissas)
alpha = numpy.random.random(len(weights))
alpha = likelihood > alpha*subset*numpy.max(likelihood)
abscissas = abscissas.T[alpha].T
weights = weights[alpha]
return abscissas, weights | def probabilistic_collocation(order, dist, subset=.1) | Probabilistic collocation method.
Args:
order (int, numpy.ndarray) : Quadrature order along each axis.
dist (Dist) : Distribution to generate samples from.
subset (float) : Rate of which to removed samples. | 5.002216 | 5.687972 | 0.879438 |
from ...distributions.baseclass import Dist
if isinstance(domain, Dist):
lower, upper = domain.range()
parameters["dist"] = domain
else:
lower, upper = numpy.array(domain)
parameters["lower"] = lower
parameters["upper"] = upper
quad_function = QUAD_FUNCTIONS[rule]
parameters_spec = inspect.getargspec(quad_function)[0]
parameters_spec = {key: None for key in parameters_spec}
del parameters_spec["order"]
for key in parameters_spec:
if key in parameters:
parameters_spec[key] = parameters[key]
def _quad_function(order, *args, **kws):
params = parameters_spec.copy()
params.update(kws)
abscissas, weights = quad_function(order, *args, **params)
# normalize if prudent:
if rule in UNORMALIZED_QUADRATURE_RULES and normalize:
if isinstance(domain, Dist):
if len(domain) == 1:
weights *= domain.pdf(abscissas).flatten()
else:
weights *= domain.pdf(abscissas)
weights /= numpy.sum(weights)
return abscissas, weights
return _quad_function | def get_function(rule, domain, normalize, **parameters) | Create a quadrature function and set default parameter values.
Args:
rule (str):
Name of quadrature rule defined in ``QUAD_FUNCTIONS``.
domain (Dist, numpy.ndarray):
Defines ``lower`` and ``upper`` that is passed quadrature rule. If
``Dist``, ``domain`` is renamed to ``dist`` and also
passed.
normalize (bool):
In the case of distributions, the abscissas and weights are not
tailored to a distribution beyond matching the bounds. If True, the
samples are normalized multiplying the weights with the density of
the distribution evaluated at the abscissas and normalized
afterwards to sum to one.
parameters (:py:data:typing.Any):
Redefining of the parameter defaults. Only add parameters that the
quadrature rule expect.
Returns:
(:py:data:typing.Callable):
Function that can be called only using argument ``order``. | 3.286551 | 2.693012 | 1.2204 |
abscissas = numpy.asarray(abscissas)
if len(abscissas.shape) == 1:
abscissas = abscissas.reshape(1, *abscissas.shape)
evals = numpy.array(evals)
poly_evals = polynomials(*abscissas).T
shape = evals.shape[1:]
evals = evals.reshape(evals.shape[0], int(numpy.prod(evals.shape[1:])))
if isinstance(rule, str):
rule = rule.upper()
if rule == "LS":
uhat = linalg.lstsq(poly_evals, evals)[0]
elif rule == "T":
uhat = rlstsq(poly_evals, evals, order=order, alpha=alpha, cross=False)
elif rule == "TC":
uhat = rlstsq(poly_evals, evals, order=order, alpha=alpha, cross=True)
else:
from sklearn.linear_model.base import LinearModel
assert isinstance(rule, LinearModel)
uhat = rule.fit(poly_evals, evals).coef_.T
evals = evals.reshape(evals.shape[0], *shape)
approx_model = chaospy.poly.sum((polynomials*uhat.T), -1)
approx_model = chaospy.poly.reshape(approx_model, shape)
if retall == 1:
return approx_model, uhat
elif retall == 2:
return approx_model, uhat, poly_evals
return approx_model | def fit_regression(
polynomials,
abscissas,
evals,
rule="LS",
retall=False,
order=0,
alpha=-1,
) | Fit a polynomial chaos expansion using linear regression.
Args:
polynomials (chaospy.poly.base.Poly):
Polynomial expansion with ``polynomials.shape=(M,)`` and
`polynomials.dim=D`.
abscissas (numpy.ndarray):
Collocation nodes with ``abscissas.shape == (D, K)``.
evals (numpy.ndarray):
Model evaluations with ``len(evals)=K``.
retall (bool):
If True return Fourier coefficients in addition to R.
order (int):
Tikhonov regularization order.
alpha (float):
Dampning parameter for the Tikhonov regularization. Calculated
automatically if negative.
Returns:
(Poly, numpy.ndarray):
Fitted polynomial with ``R.shape=evals.shape[1:]`` and ``R.dim=D``.
The Fourier coefficients in the estimation.
Examples:
>>> x, y = chaospy.variable(2)
>>> polynomials = chaospy.Poly([1, x, y])
>>> abscissas = [[-1,-1,1,1], [-1,1,-1,1]]
>>> evals = [0,1,1,2]
>>> print(chaospy.around(chaospy.fit_regression(
... polynomials, abscissas, evals), 14))
0.5q0+0.5q1+1.0 | 2.425124 | 2.573086 | 0.942496 |
coef_mat = numpy.array(coef_mat)
ordinate = numpy.array(ordinate)
dim1, dim2 = coef_mat.shape
if cross:
out = numpy.empty((dim1, dim2) + ordinate.shape[1:])
coef_mat_ = numpy.empty((dim1-1, dim2))
ordinate_ = numpy.empty((dim1-1,) + ordinate.shape[1:])
for i in range(dim1):
coef_mat_[:i] = coef_mat[:i]
coef_mat_[i:] = coef_mat[i+1:]
ordinate_[:i] = ordinate[:i]
ordinate_[i:] = ordinate[i+1:]
out[i] = rlstsq(coef_mat_, ordinate_, order, alpha, False)
return numpy.median(out, 0)
if order == 0:
tikhmat = numpy.eye(dim2)
elif order == 1:
tikhmat = numpy.zeros((dim2-1, dim2))
tikhmat[:, :-1] -= numpy.eye(dim2-1)
tikhmat[:, 1:] += numpy.eye(dim2-1)
elif order == 2:
tikhmat = numpy.zeros((dim2-2, dim2))
tikhmat[:, :-2] += numpy.eye(dim2-2)
tikhmat[:, 1:-1] -= 2*numpy.eye(dim2-2)
tikhmat[:, 2:] += numpy.eye(dim2-2)
elif order is None:
tikhmat = numpy.zeros(1)
else:
tikhmat = numpy.array(order)
assert tikhmat.shape[-1] == dim2 or tikhmat.shape in ((), (1,))
if alpha < 0 and order is not None:
gamma = 0.1
def rgcv_error(alpha):
if alpha <= 0:
return numpy.inf
coef_mat_ = numpy.dot(
coef_mat.T, coef_mat)+alpha*(numpy.dot(tikhmat.T, tikhmat))
try:
coef_mat_ = numpy.dot(linalg.inv(coef_mat_), coef_mat.T)
except linalg.LinAlgError:
return numpy.inf
abscissas = numpy.dot(coef_mat_, ordinate)
res2 = numpy.sum((numpy.dot(coef_mat, abscissas)-ordinate)**2)
coef_mat_2 = numpy.dot(coef_mat, coef_mat_)
skew = dim1*res2/numpy.trace(numpy.eye(dim1)-coef_mat_2)**2
mu2 = numpy.sum(coef_mat_2*coef_mat_2.T)/dim1
return (gamma + (1-gamma)*mu2)*skew
alphas = 10.**-numpy.arange(0, 16)
evals = numpy.array([rgcv_error(alpha) for alpha in alphas])
alpha = alphas[numpy.argmin(evals)]
out = linalg.inv(
numpy.dot(coef_mat.T, coef_mat) + alpha*numpy.dot(tikhmat.T, tikhmat))
out = numpy.dot(out, numpy.dot(coef_mat.T, ordinate))
return out | def rlstsq(coef_mat, ordinate, order=1, alpha=-1, cross=False) | Least Squares Minimization using Tikhonov regularization.
Includes method for robust generalized cross-validation.
Args:
coef_mat (numpy.ndarray):
Coefficient matrix with shape ``(M, N)``.
ordinate (numpy.ndarray):
Ordinate or "dependent variable" values with shape ``(M,)`` or
``(M, K)``. If ``ordinate`` is two-dimensional, the least-squares
solution is calculated for each of the ``K`` columns of
``ordinate``.
order (int, numpy.ndarray):
If int, it is the order of Tikhonov regularization. If
`numpy.ndarray`, it will be used as regularization matrix.
alpha (float):
Lower threshold for the dampening parameter. The real value is
calculated using generalised cross validation.
cross (bool):
Use cross validation to estimate alpha value. | 2.235733 | 2.274507 | 0.982953 |
order = sorted(GENZ_KEISTER_24.keys())[order]
abscissas, weights = GENZ_KEISTER_24[order]
abscissas = numpy.array(abscissas)
weights = numpy.array(weights)
weights /= numpy.sum(weights)
abscissas *= numpy.sqrt(2)
return abscissas, weights | def quad_genz_keister_24 ( order ) | Hermite Genz-Keister 24 rule.
Args:
order (int):
The quadrature order. Must be in the interval (0, 8).
Returns:
(:py:data:typing.Tuple[numpy.ndarray, numpy.ndarray]):
Abscissas and weights
Examples:
>>> abscissas, weights = quad_genz_keister_24(1)
>>> print(numpy.around(abscissas, 4))
[-1.7321 0. 1.7321]
>>> print(numpy.around(weights, 4))
[0.1667 0.6667 0.1667] | 2.768613 | 3.528265 | 0.784695 |
try:
args = inspect.signature(caller).parameters
except AttributeError:
args = inspect.getargspec(caller).args
return key in args | def contains_call_signature(caller, key) | Check if a function or method call signature contains a specific
argument.
Args:
caller (Callable):
Method or function to check if signature is contain in.
key (str):
Signature to look for.
Returns:
True if ``key`` exits in ``caller`` call signature.
Examples:
>>> def foo(param): pass
>>> contains_call_signature(foo, "param")
True
>>> contains_call_signature(foo, "not_param")
False
>>> class Bar:
... def baz(self, param): pass
>>> bar = Bar()
>>> contains_call_signature(bar.baz, "param")
True
>>> contains_call_signature(bar.baz, "not_param")
False | 3.316486 | 4.966848 | 0.667724 |
dim = len(dist)
generator = Saltelli(dist, samples, poly, rule=rule)
zeros = [0]*dim
ones = [1]*dim
index = [0]*dim
variance = numpy.var(generator[zeros], -1)
matrix_0 = generator[zeros]
matrix_1 = generator[ones]
mean = .5*(numpy.mean(matrix_1) + numpy.mean(matrix_0))
matrix_0 -= mean
matrix_1 -= mean
out = [
numpy.mean(matrix_1*((generator[index]-mean)-matrix_0), -1) /
numpy.where(variance, variance, 1)
for index in numpy.eye(dim, dtype=bool)
]
return numpy.array(out) | def Sens_m_sample(poly, dist, samples, rule="R") | First order sensitivity indices estimated using Saltelli's method.
Args:
poly (chaospy.Poly):
If provided, evaluated samples through polynomials before returned.
dist (chaopy.Dist):
distribution to sample from.
samples (int):
The number of samples to draw for each matrix.
rule (str):
Scheme for generating random samples.
Return:
(numpy.ndarray):
array with `shape == (len(dist), len(poly))` where `sens[dim][pol]`
is the first sensitivity index for distribution dimensions `dim` and
polynomial index `pol`.
Examples:
>>> dist = chaospy.Iid(chaospy.Uniform(), 2)
>>> poly = chaospy.basis(2, 2, dim=2)
>>> print(poly)
[q0^2, q0q1, q1^2]
>>> print(numpy.around(Sens_m_sample(poly, dist, 10000, rule="M"), 4))
[[0.008 0.0026 0. ]
[0. 0.6464 2.1321]] | 4.492112 | 5.032916 | 0.892547 |
dim = len(dist)
generator = Saltelli(dist, samples, poly, rule=rule)
zeros = [0]*dim
ones = [1]*dim
index = [0]*dim
variance = numpy.var(generator[zeros], -1)
matrix_0 = generator[zeros]
matrix_1 = generator[ones]
mean = .5*(numpy.mean(matrix_1) + numpy.mean(matrix_0))
matrix_0 -= mean
matrix_1 -= mean
out = numpy.empty((dim, dim)+poly.shape)
for dim1 in range(dim):
index[dim1] = 1
matrix = generator[index]-mean
out[dim1, dim1] = numpy.mean(
matrix_1*(matrix-matrix_0),
-1,
) / numpy.where(variance, variance, 1)
for dim2 in range(dim1+1, dim):
index[dim2] = 1
matrix = generator[index]-mean
out[dim1, dim2] = out[dim2, dim1] = numpy.mean(
matrix_1*(matrix-matrix_0),
-1,
) / numpy.where(variance, variance, 1)
index[dim2] = 0
index[dim1] = 0
return out | def Sens_m2_sample(poly, dist, samples, rule="R") | Second order sensitivity indices estimated using Saltelli's method.
Args:
poly (chaospy.Poly):
If provided, evaluated samples through polynomials before returned.
dist (chaopy.Dist):
distribution to sample from.
samples (int):
The number of samples to draw for each matrix.
rule (str):
Scheme for generating random samples.
Return:
(numpy.ndarray):
array with `shape == (len(dist), len(dist), len(poly))` where
`sens[dim1][dim2][pol]` is the correlating sensitivity between
dimension `dim1` and `dim2` and polynomial index `pol`.
Examples:
>>> dist = chaospy.Iid(chaospy.Uniform(), 2)
>>> poly = chaospy.basis(2, 2, dim=2)
>>> print(poly)
[q0^2, q0q1, q1^2]
>>> print(numpy.around(Sens_m2_sample(poly, dist, 10000, rule="H"), 4))
[[[ 0.008 0.0026 0. ]
[-0.0871 1.1516 1.2851]]
<BLANKLINE>
[[-0.0871 1.1516 1.2851]
[ 0. 0.7981 1.38 ]]] | 2.957716 | 3.024245 | 0.978001 |
generator = Saltelli(dist, samples, poly, rule=rule)
dim = len(dist)
zeros = [0]*dim
variance = numpy.var(generator[zeros], -1)
return numpy.array([
1-numpy.mean((generator[~index]-generator[zeros])**2, -1,) /
(2*numpy.where(variance, variance, 1))
for index in numpy.eye(dim, dtype=bool)
]) | def Sens_t_sample(poly, dist, samples, rule="R") | Total order sensitivity indices estimated using Saltelli's method.
Args:
poly (chaospy.Poly):
If provided, evaluated samples through polynomials before returned.
dist (chaopy.Dist):
distribution to sample from.
samples (int):
The number of samples to draw for each matrix.
rule (str):
Scheme for generating random samples.
Return:
(numpy.ndarray):
array with `shape == (len(dist), len(poly))` where `sens[dim][pol]`
is the total order sensitivity index for distribution dimensions
`dim` and polynomial index `pol`.
Examples:
>>> dist = chaospy.Iid(chaospy.Uniform(0, 1), 2)
>>> poly = chaospy.basis(2, 2, dim=2)
>>> print(poly)
[q0^2, q0q1, q1^2]
>>> print(numpy.around(Sens_t_sample(poly, dist, 10000, rule="H"), 4))
[[ 1. 0.2 -0.3807]
[ 0.9916 0.9962 1. ]] | 7.236266 | 8.502597 | 0.851065 |
new = numpy.empty(self.samples1.shape)
for idx in range(len(indices)):
if indices[idx]:
new[idx] = self.samples1[idx]
else:
new[idx] = self.samples2[idx]
if self.poly:
new = self.poly(*new)
return new | def get_matrix(self, indices) | Retrieve Saltelli matrix. | 3.690748 | 3.636377 | 1.014952 |
left = evaluation.get_forward_cache(left, cache)
right = evaluation.get_forward_cache(right, cache)
if isinstance(left, Dist):
if isinstance(right, Dist):
raise evaluation.DependencyError(
"under-defined distribution {} or {}".format(left, right))
elif not isinstance(right, Dist):
return left+right, left+right
else:
left, right = right, left
right = numpy.asfarray(right)
if len(right.shape) == 3:
xloc_ = (xloc.T-right[0].T).T
lower, upper = evaluation.evaluate_bound(left, xloc_, cache=cache.copy())
lower0, upper0 = (lower.T+right[0].T).T, (upper.T+right[0].T).T
xloc_ = (xloc.T-right[1].T).T
lower, upper = evaluation.evaluate_bound(left, xloc_, cache=cache)
lower1, upper1 = (lower.T+right[1].T).T, (upper.T+right[1].T).T
lower = numpy.min([lower0, lower1], 0)
upper = numpy.max([upper0, upper1], 0)
else:
xloc_ = (xloc.T-right.T).T
lower, upper = evaluation.evaluate_bound(left, xloc_, cache=cache.copy())
lower, upper = (lower.T+right.T).T, (upper.T+right.T).T
assert lower.shape == xloc.shape
assert upper.shape == xloc.shape
return lower, upper | def _bnd(self, xloc, left, right, cache) | Distribution bounds.
Example:
>>> print(chaospy.Uniform().range([-2, 0, 2, 4]))
[[0. 0. 0. 0.]
[1. 1. 1. 1.]]
>>> print(chaospy.Add(chaospy.Uniform(), 2).range([-2, 0, 2, 4]))
[[2. 2. 2. 2.]
[3. 3. 3. 3.]]
>>> print(chaospy.Add(2, chaospy.Uniform()).range([-2, 0, 2, 4]))
[[2. 2. 2. 2.]
[3. 3. 3. 3.]]
>>> print(chaospy.Add(1, 1).range([-2, 0, 2, 4]))
[[2. 2. 2. 2.]
[2. 2. 2. 2.]] | 2.246402 | 2.302068 | 0.975819 |
left = evaluation.get_forward_cache(left, cache)
right = evaluation.get_forward_cache(right, cache)
if isinstance(left, Dist):
if isinstance(right, Dist):
raise evaluation.DependencyError(
"under-defined distribution {} or {}".format(left, right))
elif not isinstance(right, Dist):
return numpy.asfarray(left+right <= xloc)
else:
left, right = right, left
xloc = (xloc.T-numpy.asfarray(right).T).T
output = evaluation.evaluate_forward(left, xloc, cache=cache)
assert output.shape == xloc.shape
return output | def _cdf(self, xloc, left, right, cache) | Cumulative distribution function.
Example:
>>> print(chaospy.Uniform().fwd([-0.5, 0.5, 1.5, 2.5]))
[0. 0.5 1. 1. ]
>>> print(chaospy.Add(chaospy.Uniform(), 1).fwd([-0.5, 0.5, 1.5, 2.5]))
[0. 0. 0.5 1. ]
>>> print(chaospy.Add(1, chaospy.Uniform()).fwd([-0.5, 0.5, 1.5, 2.5]))
[0. 0. 0.5 1. ]
>>> print(chaospy.Add(1, 1).fwd([-0.5, 0.5, 1.5, 2.5]))
[0. 0. 0. 1.] | 4.178553 | 4.541179 | 0.920147 |
left = evaluation.get_forward_cache(left, cache)
right = evaluation.get_forward_cache(right, cache)
if isinstance(left, Dist):
if isinstance(right, Dist):
raise evaluation.DependencyError(
"under-defined distribution {} or {}".format(left, right))
elif not isinstance(right, Dist):
return numpy.inf
else:
left, right = right, left
xloc = (xloc.T-numpy.asfarray(right).T).T
output = evaluation.evaluate_density(left, xloc, cache=cache)
assert output.shape == xloc.shape
return output | def _pdf(self, xloc, left, right, cache) | Probability density function.
Example:
>>> print(chaospy.Uniform().pdf([-2, 0, 2, 4]))
[0. 1. 0. 0.]
>>> print(chaospy.Add(chaospy.Uniform(), 2).pdf([-2, 0, 2, 4]))
[0. 0. 1. 0.]
>>> print(chaospy.Add(2, chaospy.Uniform()).pdf([-2, 0, 2, 4]))
[0. 0. 1. 0.]
>>> print(chaospy.Add(1, 1).pdf([-2, 0, 2, 4])) # Dirac logic
[ 0. 0. inf 0.] | 4.129701 | 4.577256 | 0.902222 |
left = evaluation.get_inverse_cache(left, cache)
right = evaluation.get_inverse_cache(right, cache)
if isinstance(left, Dist):
if isinstance(right, Dist):
raise evaluation.DependencyError(
"under-defined distribution {} or {}".format(left, right))
elif not isinstance(right, Dist):
return left+right
else:
left, right = right, left
xloc = evaluation.evaluate_inverse(left, uloc, cache=cache)
output = (xloc.T + numpy.asfarray(right).T).T
return output | def _ppf(self, uloc, left, right, cache) | Point percentile function.
Example:
>>> print(chaospy.Uniform().inv([0.1, 0.2, 0.9]))
[0.1 0.2 0.9]
>>> print(chaospy.Add(chaospy.Uniform(), 2).inv([0.1, 0.2, 0.9]))
[2.1 2.2 2.9]
>>> print(chaospy.Add(2, chaospy.Uniform()).inv([0.1, 0.2, 0.9]))
[2.1 2.2 2.9]
>>> print(chaospy.Add(1, 1).inv([0.1, 0.2, 0.9]))
[2. 2. 2.] | 4.383789 | 4.991502 | 0.878251 |
if evaluation.get_dependencies(left, right):
raise evaluation.DependencyError(
"sum of dependent distributions not feasible: "
"{} and {}".format(left, right)
)
keys_ = numpy.mgrid[tuple(slice(0, key+1, 1) for key in keys)]
keys_ = keys_.reshape(len(self), -1)
if isinstance(left, Dist):
left = [
evaluation.evaluate_moment(left, key, cache=cache)
for key in keys_.T
]
else:
left = list(reversed(numpy.array(left).T**keys_.T))
if isinstance(right, Dist):
right = [
evaluation.evaluate_moment(right, key, cache=cache)
for key in keys_.T
]
else:
right = list(reversed(numpy.array(right).T**keys_.T))
out = numpy.zeros(keys.shape)
for idx in range(keys_.shape[1]):
key = keys_.T[idx]
coef = comb(keys.T, key)
out += coef*left[idx]*right[idx]*(key <= keys.T)
if len(self) > 1:
out = numpy.prod(out, 1)
return out | def _mom(self, keys, left, right, cache) | Statistical moments.
Example:
>>> print(numpy.around(chaospy.Uniform().mom([0, 1, 2, 3]), 4))
[1. 0.5 0.3333 0.25 ]
>>> print(numpy.around(chaospy.Add(chaospy.Uniform(), 2).mom([0, 1, 2, 3]), 4))
[ 1. 2.5 6.3333 16.25 ]
>>> print(numpy.around(chaospy.Add(2, chaospy.Uniform()).mom([0, 1, 2, 3]), 4))
[ 1. 2.5 6.3333 16.25 ]
>>> print(numpy.around(chaospy.Add(1, 1).mom([0, 1, 2, 3]), 4))
[1. 2. 4. 8.] | 3.365453 | 3.448684 | 0.975866 |
if isinstance(left, Dist):
if isinstance(right, Dist):
raise StochasticallyDependentError(
"sum of distributions not feasible: "
"{} and {}".format(left, right)
)
else:
if not isinstance(right, Dist):
raise StochasticallyDependentError(
"recurrence coefficients for constants not feasible: "
"{}".format(left+right)
)
left, right = right, left
coeff0, coeff1 = evaluation.evaluate_recurrence_coefficients(
left, kloc, cache=cache)
return coeff0 + numpy.asarray(right), coeff1 | def _ttr(self, kloc, left, right, cache) | Three terms recursion coefficients.
Example:
>>> print(numpy.around(chaospy.Uniform().ttr([0, 1, 2, 3]), 4))
[[ 0.5 0.5 0.5 0.5 ]
[-0. 0.0833 0.0667 0.0643]]
>>> print(numpy.around(chaospy.Add(chaospy.Uniform(), 2).ttr([0, 1, 2, 3]), 4))
[[ 2.5 2.5 2.5 2.5 ]
[-0. 0.0833 0.0667 0.0643]]
>>> print(numpy.around(chaospy.Add(2, chaospy.Uniform()).ttr([0, 1, 2, 3]), 4))
[[ 2.5 2.5 2.5 2.5 ]
[-0. 0.0833 0.0667 0.0643]]
>>> print(numpy.around(chaospy.Add(1, 1).ttr([0, 1, 2, 3]), 4)) # doctest: +IGNORE_EXCEPTION_DETAIL
Traceback (most recent call last):
...
chaospy.distributions.baseclass.StochasticallyDependentError: recurrence ... | 4.772212 | 4.011666 | 1.189584 |
from .. import distributions
assert not distributions.evaluation.get_dependencies(dist)
if len(dist) > 1:
# one for each dimension:
orth, norms, coeff1, coeff2 = zip(*[generate_stieltjes(
_, order, accuracy, normed, retall=True, **kws) for _ in dist])
# ensure each polynomial has its own dimension:
orth = [[chaospy.setdim(_, len(orth)) for _ in poly] for poly in orth]
orth = [[chaospy.rolldim(_, len(dist)-idx) for _ in poly] for idx, poly in enumerate(orth)]
orth = [chaospy.poly.base.Poly(_) for _ in zip(*orth)]
if not retall:
return orth
# stack results:
norms = numpy.vstack(norms)
coeff1 = numpy.vstack(coeff1)
coeff2 = numpy.vstack(coeff2)
return orth, norms, coeff1, coeff2
try:
orth, norms, coeff1, coeff2 = _stieltjes_analytical(
dist, order, normed)
except NotImplementedError:
orth, norms, coeff1, coeff2 = _stieltjes_approx(
dist, order, accuracy, normed, **kws)
if retall:
assert not numpy.any(numpy.isnan(coeff1))
assert not numpy.any(numpy.isnan(coeff2))
return orth, norms, coeff1, coeff2
return orth | def generate_stieltjes(
dist, order, accuracy=100, normed=False, retall=False, **kws) | Discretized Stieltjes' method.
Args:
dist (Dist):
Distribution defining the space to create weights for.
order (int):
The polynomial order create.
accuracy (int):
The quadrature order of the Clenshaw-Curtis nodes to
use at each step, if approximation is used.
retall (bool):
If included, more values are returned
Returns:
(list): List of polynomials, norms of polynomials and three terms
coefficients. The list created from the method with
``len(orth) == order+1``. If ``len(dist) > 1``, then each
polynomials are multivariate.
(numpy.ndarray, numpy.ndarray, numpy.ndarray): If ``retall`` is true,
also return polynomial norms and the three term coefficients.
The norms of the polynomials with ``norms.shape = (dim, order+1)``
where ``dim`` are the number of dimensions in dist. The
coefficients have ``shape == (dim, order+1)``.
Examples:
>>> dist = chaospy.J(chaospy.Normal(), chaospy.Weibull())
>>> orth, norms, coeffs1, coeffs2 = chaospy.generate_stieltjes(
... dist, 2, retall=True)
>>> print(chaospy.around(orth[2], 5))
[q0^2-1.0, q1^2-4.0q1+2.0]
>>> print(numpy.around(norms, 5))
[[1. 1. 2.]
[1. 1. 4.]]
>>> print(numpy.around(coeffs1, 5))
[[0. 0. 0.]
[1. 3. 5.]]
>>> print(numpy.around(coeffs2, 5))
[[1. 1. 2.]
[1. 1. 4.]]
>>> dist = chaospy.Uniform()
>>> orth, norms, coeffs1, coeffs2 = chaospy.generate_stieltjes(
... dist, 2, retall=True)
>>> print(chaospy.around(orth[2], 8))
q0^2-q0+0.16666667
>>> print(numpy.around(norms, 4))
[[1. 0.0833 0.0056]] | 3.121947 | 2.791192 | 1.1185 |
dimensions = len(dist)
mom_order = numpy.arange(order+1).repeat(dimensions)
mom_order = mom_order.reshape(order+1, dimensions).T
coeff1, coeff2 = dist.ttr(mom_order)
coeff2[:, 0] = 1.
poly = chaospy.poly.collection.core.variable(dimensions)
if normed:
orth = [
poly**0*numpy.ones(dimensions),
(poly-coeff1[:, 0])/numpy.sqrt(coeff2[:, 1]),
]
for order_ in range(1, order):
orth.append(
(orth[-1]*(poly-coeff1[:, order_])
-orth[-2]*numpy.sqrt(coeff2[:, order_]))
/numpy.sqrt(coeff2[:, order_+1])
)
norms = numpy.ones(coeff2.shape)
else:
orth = [poly-poly, poly**0*numpy.ones(dimensions)]
for order_ in range(order):
orth.append(
orth[-1]*(poly-coeff1[:, order_])
- orth[-2]*coeff2[:, order_]
)
orth = orth[1:]
norms = numpy.cumprod(coeff2, 1)
return orth, norms, coeff1, coeff2 | def _stieltjes_analytical(dist, order, normed) | Stieltjes' method with analytical recurrence coefficients. | 3.352756 | 3.357859 | 0.99848 |
kws["rule"] = kws.get("rule", "C")
assert kws["rule"].upper() != "G"
absisas, weights = chaospy.quad.generate_quadrature(
accuracy, dist.range(), **kws)
weights = weights*dist.pdf(absisas)
poly = chaospy.poly.variable(len(dist))
orth = [poly*0, poly**0]
inner = numpy.sum(absisas*weights, -1)
norms = [numpy.ones(len(dist)), numpy.ones(len(dist))]
coeff1 = []
coeff2 = []
for _ in range(order):
coeff1.append(inner/norms[-1])
coeff2.append(norms[-1]/norms[-2])
orth.append((poly-coeff1[-1])*orth[-1] - orth[-2]*coeff2[-1])
raw_nodes = orth[-1](*absisas)**2*weights
inner = numpy.sum(absisas*raw_nodes, -1)
norms.append(numpy.sum(raw_nodes, -1))
if normed:
orth[-1] = orth[-1]/numpy.sqrt(norms[-1])
coeff1.append(inner/norms[-1])
coeff2.append(norms[-1]/norms[-2])
coeff1 = numpy.transpose(coeff1)
coeff2 = numpy.transpose(coeff2)
norms = numpy.array(norms[1:]).T
orth = orth[1:]
return orth, norms, coeff1, coeff2 | def _stieltjes_approx(dist, order, accuracy, normed, **kws) | Stieltjes' method with approximative recurrence coefficients. | 3.391399 | 3.344496 | 1.014024 |
global RANDOM_SEED # pylint: disable=global-statement
if seed_value is not None:
RANDOM_SEED = seed_value
if step is not None:
RANDOM_SEED += step | def set_state(seed_value=None, step=None) | Set random seed. | 2.277779 | 2.031771 | 1.12108 |
assert 0 < dim < DIM_MAX, "dim in [1, 40]"
# global RANDOM_SEED # pylint: disable=global-statement
# if seed is None:
# seed = RANDOM_SEED
# RANDOM_SEED += order
set_state(seed_value=seed)
seed = RANDOM_SEED
set_state(step=order)
# Initialize row 1 of V.
samples = SOURCE_SAMPLES.copy()
maxcol = int(math.log(2**LOG_MAX-1, 2))+1
samples[0, 0:maxcol] = 1
# Initialize the remaining rows of V.
for idx in range(1, dim):
# The bits of the integer POLY(I) gives the form of polynomial:
degree = int(math.log(POLY[idx], 2))
#Expand this bit pattern to separate components:
includ = numpy.array([val == "1" for val in bin(POLY[idx])[-degree:]])
#Calculate the remaining elements of row I as explained
#in Bratley and Fox, section 2.
for idy in range(degree+1, maxcol+1):
newv = samples[idx, idy-degree-1].item()
base = 1
for idz in range(1, degree+1):
base *= 2
if includ[idz-1]:
newv = newv ^ base * samples[idx, idy-idz-1].item()
samples[idx, idy-1] = newv
samples = samples[:dim]
# Multiply columns of V by appropriate power of 2.
samples *= 2**(numpy.arange(maxcol, 0, -1, dtype=int))
#RECIPD is 1/(common denominator of the elements in V).
recipd = 0.5**(maxcol+1)
lastq = numpy.zeros(dim, dtype=int)
seed = int(seed) if seed > 1 else 1
for seed_ in range(seed):
lowbit = len(bin(seed_)[2:].split("0")[-1])
lastq[:] = lastq ^ samples[:, lowbit]
#Calculate the new components of QUASI.
quasi = numpy.empty((dim, order))
for idx in range(order):
lowbit = len(bin(seed+idx)[2:].split("0")[-1])
quasi[:, idx] = lastq * recipd
lastq[:] = lastq ^ samples[:, lowbit]
return quasi | def create_sobol_samples(order, dim, seed=1) | Args:
order (int):
Number of unique samples to generate.
dim (int):
Number of spacial dimensions. Must satisfy ``0 < dim < 41``.
seed (int):
Starting seed. Non-positive values are treated as 1. If omitted,
consecutive samples are used.
Returns:
(numpy.ndarray):
Quasi-random vector with ``shape == (dim, order)``. | 5.386804 | 5.369176 | 1.003283 |
dim = len(funcs)
tensprod_rule = create_tensorprod_function(funcs)
assert hasattr(tensprod_rule, "__call__")
mv_rule = create_mv_rule(tensprod_rule, dim)
assert hasattr(mv_rule, "__call__")
return mv_rule | def rule_generator(*funcs) | Constructor for creating multivariate quadrature generator.
Args:
funcs (:py:data:typing.Callable):
One dimensional integration rule where each rule returns
``abscissas`` and ``weights`` as one dimensional arrays. They must
take one positional argument ``order``.
Returns:
(:py:data:typing.Callable):
Multidimensional integration quadrature function that takes the
arguments ``order`` and ``sparse``, and a optional ``part``. The
argument ``sparse`` is used to select for if Smolyak sparse grid is
used, and ``part`` defines if subset of rule should be generated
(for parallelization).
Example:
>>> clenshaw_curtis = lambda order: chaospy.quad_clenshaw_curtis(
... order, lower=-1, upper=1, growth=True)
>>> gauss_legendre = lambda order: chaospy.quad_gauss_legendre(
... order, lower=0, upper=1)
>>> quad_func = chaospy.rule_generator(clenshaw_curtis, gauss_legendre)
>>> abscissas, weights = quad_func(1)
>>> print(numpy.around(abscissas, 4))
[[-1. -1. 0. 0. 1. 1. ]
[ 0.2113 0.7887 0.2113 0.7887 0.2113 0.7887]]
>>> print(numpy.around(weights, 4))
[0.1667 0.1667 0.6667 0.6667 0.1667 0.1667] | 4.869684 | 7.647551 | 0.636764 |
dim = len(funcs)
def tensprod_rule(order, part=None):
order = order*numpy.ones(dim, int)
values = [funcs[idx](order[idx]) for idx in range(dim)]
abscissas = [numpy.array(_[0]).flatten() for _ in values]
abscissas = chaospy.quad.combine(abscissas, part=part).T
weights = [numpy.array(_[1]).flatten() for _ in values]
weights = numpy.prod(chaospy.quad.combine(weights, part=part), -1)
return abscissas, weights
return tensprod_rule | def create_tensorprod_function(funcs) | Combine 1-D rules into multivariate rule using tensor product. | 3.760374 | 3.510577 | 1.071155 |
def mv_rule(order, sparse=False, part=None):
if sparse:
order = numpy.ones(dim, dtype=int)*order
tensorprod_rule_ = lambda order, part=part:\
tensorprod_rule(order, part=part)
return chaospy.quad.sparse_grid(tensorprod_rule_, order)
return tensorprod_rule(order, part=part)
return mv_rule | def create_mv_rule(tensorprod_rule, dim) | Convert tensor product rule into a multivariate quadrature generator. | 5.065554 | 4.809331 | 1.053276 |
order = numpy.asarray(order, dtype=int).flatten()
lower = numpy.asarray(lower).flatten()
upper = numpy.asarray(upper).flatten()
dim = max(lower.size, upper.size, order.size)
order = numpy.ones(dim, dtype=int)*order
lower = numpy.ones(dim)*lower
upper = numpy.ones(dim)*upper
composite = numpy.array([numpy.arange(2)]*dim)
if growth:
results = [
_fejer(numpy.where(order[i] == 0, 0, 2.**(order[i]+1)-2))
for i in range(dim)
]
else:
results = [
_fejer(order[i], composite[i]) for i in range(dim)
]
abscis = [_[0] for _ in results]
weight = [_[1] for _ in results]
abscis = chaospy.quad.combine(abscis, part=part).T
weight = chaospy.quad.combine(weight, part=part)
abscis = ((upper-lower)*abscis.T + lower).T
weight = numpy.prod(weight*(upper-lower), -1)
assert len(abscis) == dim
assert len(weight) == len(abscis.T)
return abscis, weight | def quad_fejer(order, lower=0, upper=1, growth=False, part=None) | Generate the quadrature abscissas and weights in Fejer quadrature.
Example:
>>> abscissas, weights = quad_fejer(3, 0, 1)
>>> print(numpy.around(abscissas, 4))
[[0.0955 0.3455 0.6545 0.9045]]
>>> print(numpy.around(weights, 4))
[0.1804 0.2996 0.2996 0.1804] | 2.864366 | 2.882109 | 0.993844 |
r
order = int(order)
if order == 0:
return numpy.array([.5]), numpy.array([1.])
order += 2
theta = (order-numpy.arange(order+1))*numpy.pi/order
abscisas = 0.5*numpy.cos(theta) + 0.5
N, K = numpy.mgrid[:order+1, :order//2]
weights = 2*numpy.cos(2*(K+1)*theta[N])/(4*K*(K+2)+3)
if order % 2 == 0:
weights[:, -1] *= 0.5
weights = (1-numpy.sum(weights, -1)) / order
return abscisas[1:-1], weights[1:-1] | def _fejer(order, composite=None) | r"""
Backend method.
Examples:
>>> abscissas, weights = _fejer(0)
>>> print(abscissas)
[0.5]
>>> print(weights)
[1.]
>>> abscissas, weights = _fejer(1)
>>> print(abscissas)
[0.25 0.75]
>>> print(weights)
[0.44444444 0.44444444]
>>> abscissas, weights = _fejer(2)
>>> print(abscissas)
[0.14644661 0.5 0.85355339]
>>> print(weights)
[0.26666667 0.4 0.26666667]
>>> abscissas, weights = _fejer(3)
>>> print(abscissas)
[0.0954915 0.3454915 0.6545085 0.9045085]
>>> print(weights)
[0.18037152 0.29962848 0.29962848 0.18037152]
>>> abscissas, weights = _fejer(4)
>>> print(abscissas)
[0.0669873 0.25 0.5 0.75 0.9330127]
>>> print(weights)
[0.12698413 0.22857143 0.26031746 0.22857143 0.12698413]
>>> abscissas, weights = _fejer(5)
>>> print(abscissas)
[0.04951557 0.1882551 0.38873953 0.61126047 0.8117449 0.95048443]
>>> print(weights)
[0.0950705 0.17612121 0.2186042 0.2186042 0.17612121 0.0950705 ] | 4.569037 | 4.336087 | 1.053724 |
randoms = numpy.random.random(order*dim).reshape((dim, order))
for dim_ in range(dim):
perm = numpy.random.permutation(order) # pylint: disable=no-member
randoms[dim_] = (perm + randoms[dim_])/order
return randoms | def create_latin_hypercube_samples(order, dim=1) | Latin Hypercube sampling.
Args:
order (int):
The order of the latin hyper-cube. Defines the number of samples.
dim (int):
The number of dimensions in the latin hyper-cube.
Returns (numpy.ndarray):
Latin hyper-cube with ``shape == (dim, order)``. | 3.999766 | 4.679789 | 0.85469 |
if dim == 1:
return create_halton_samples(
order=order, dim=1, burnin=burnin, primes=primes)
out = numpy.empty((dim, order), dtype=float)
out[:dim-1] = create_halton_samples(
order=order, dim=dim-1, burnin=burnin, primes=primes)
out[dim-1] = numpy.linspace(0, 1, order+2)[1:-1]
return out | def create_hammersley_samples(order, dim=1, burnin=-1, primes=()) | Create samples from the Hammersley set.
For ``dim == 1`` the sequence falls back to Van Der Corput sequence.
Args:
order (int):
The order of the Hammersley sequence. Defines the number of samples.
dim (int):
The number of dimensions in the Hammersley sequence.
burnin (int):
Skip the first ``burnin`` samples. If negative, the maximum of
``primes`` is used.
primes (tuple):
The (non-)prime base to calculate values along each axis. If
empty, growing prime values starting from 2 will be used.
Returns:
(numpy.ndarray):
Hammersley set with ``shape == (dim, order)``. | 2.15474 | 2.248474 | 0.958312 |
if threshold == 2:
return [2]
elif threshold < 2:
return []
numbers = list(range(3, threshold+1, 2))
root_of_threshold = threshold ** 0.5
half = int((threshold+1)/2-1)
idx = 0
counter = 3
while counter <= root_of_threshold:
if numbers[idx]:
idy = int((counter*counter-3)/2)
numbers[idy] = 0
while idy < half:
numbers[idy] = 0
idy += counter
idx += 1
counter = 2*idx+3
return [2] + [number for number in numbers if number] | def create_primes(threshold) | Generate prime values using sieve of Eratosthenes method.
Args:
threshold (int):
The upper bound for the size of the prime values.
Returns (List[int]):
All primes from 2 and up to ``threshold``. | 2.975603 | 2.904883 | 1.024345 |
if cache is None:
cache = {}
out = numpy.zeros(u_data.shape)
# Distribution self know how to handle inverse Rosenblatt.
if hasattr(distribution, "_ppf"):
parameters = load_parameters(
distribution, "_ppf", parameters=parameters, cache=cache)
out[:] = distribution._ppf(u_data.copy(), **parameters)
# Approximate inverse Rosenblatt based on cumulative distribution function.
else:
from .. import approximation
parameters = load_parameters(
distribution, "_cdf", parameters=parameters, cache=cache)
out[:] = approximation.approximate_inverse(
distribution, u_data.copy(), cache=cache.copy(), parameters=parameters)
# Store cache.
cache[distribution] = out
return out | def evaluate_inverse(
distribution,
u_data,
cache=None,
parameters=None
) | Evaluate inverse Rosenblatt transformation.
Args:
distribution (Dist):
Distribution to evaluate.
u_data (numpy.ndarray):
Locations for where evaluate inverse transformation distribution at.
parameters (:py:data:typing.Any):
Collection of parameters to override the default ones in the
distribution.
cache (:py:data:typing.Any):
A collection of previous calculations in case the same distribution
turns up on more than one occasion.
Returns:
The cumulative distribution values of ``distribution`` at location
``u_data`` using parameters ``parameters``. | 4.090717 | 3.725384 | 1.098066 |
if (idxi, idxj, idxk) in self.hist:
return self.hist[idxi, idxj, idxk]
if idxi == idxk == 0 or idxi == idxj == 0:
out = 0
elif chaospy.bertran.add(idxi, idxk, self.dim) < idxj \
or chaospy.bertran.add(idxi, idxj, self.dim) < idxk:
out = 0
elif chaospy.bertran.add(idxi, idxj, self.dim) == idxk:
out = 1
elif idxj == idxk == 0:
out = self.dist.mom(chaospy.bertran.multi_index(idxi, self.dim))
elif idxk == 0:
out = self.mom_110(idxi, idxj, idxk)
else:
out = self.mom_recurse(idxi, idxj, idxk)
self.hist[idxi, idxj, idxk] = out
return out | def mom_111(self, idxi, idxj, idxk) | Backend moment for i, j, k == 1, 1, 1. | 2.429499 | 2.405323 | 1.010051 |
rank_ = min(
chaospy.bertran.rank(idxi, self.dim),
chaospy.bertran.rank(idxj, self.dim),
chaospy.bertran.rank(idxk, self.dim)
)
par, axis0 = chaospy.bertran.parent(idxj, self.dim)
gpar, _ = chaospy.bertran.parent(par, self.dim, axis0)
idxi_child = chaospy.bertran.child(idxi, self.dim, axis0)
oneup = chaospy.bertran.child(0, self.dim, axis0)
out = self(idxi_child, par, 0)
for k in range(gpar, idxj):
if chaospy.bertran.rank(k, self.dim) >= rank_:
out -= self.mom_111(oneup, par, k) * self.mom_111(idxi, k, 0)
return out | def mom_110(self, idxi, idxj, idxk) | Backend moment for i, j, k == 1, 1, 1. | 3.399202 | 3.388896 | 1.003041 |
rank_ = min(
chaospy.bertran.rank(idxi, self.dim),
chaospy.bertran.rank(idxj, self.dim),
chaospy.bertran.rank(idxk, self.dim)
)
par, axis0 = chaospy.bertran.parent(idxk, self.dim)
gpar, _ = chaospy.bertran.parent(par, self.dim, axis0)
idxi_child = chaospy.bertran.child(idxi, self.dim, axis0)
oneup = chaospy.bertran.child(0, self.dim, axis0)
out1 = self.mom_111(idxi_child, idxj, par)
out2 = self.mom_111(
chaospy.bertran.child(oneup, self.dim, axis0), par, par)
for k in range(gpar, idxk):
if chaospy.bertran.rank(k, self.dim) >= rank_:
out1 -= self.mom_111(oneup, k, par) \
* self.mom_111(idxi, idxj, k)
out2 -= self.mom_111(oneup, par, k) \
* self(oneup, k, par)
return out1 / out2 | def mom_recurse(self, idxi, idxj, idxk) | Backend mement main loop. | 2.939461 | 2.914077 | 1.008711 |
assert dist.__class__.__name__ == "Copula"
trans = dist.prm["trans"]
assert trans.__class__.__name__ == "nataf"
vals = numpy.array(vals)
cov = trans.prm["C"]
cov = numpy.dot(cov, cov.T)
marginal = dist.prm["dist"]
dim = len(dist)
orth = chaospy.orthogonal.orth_ttr(order, marginal, sort="GR")
r = range(dim)
index = [1] + [0]*(dim-1)
nataf = chaospy.dist.Nataf(marginal, cov, r)
samples_ = marginal.inv( nataf.fwd( samples ) )
poly, coeffs = chaospy.collocation.fit_regression(
orth, samples_, vals, retall=1)
V = Var(poly, marginal, **kws)
out = numpy.zeros((dim,) + poly.shape)
out[0] = Var(E_cond(poly, index, marginal, **kws),
marginal, **kws)/(V+(V == 0))*(V != 0)
for i in range(1, dim):
r = r[1:] + r[:1]
index = index[-1:] + index[:-1]
nataf = chaospy.dist.Nataf(marginal, cov, r)
samples_ = marginal.inv( nataf.fwd( samples ) )
poly, coeffs = chaospy.collocation.fit_regression(
orth, samples_, vals, retall=1)
out[i] = Var(E_cond(poly, index, marginal, **kws),
marginal, **kws)/(V+(V == 0))*(V != 0)
return out | def Sens_m_nataf(order, dist, samples, vals, **kws) | Variance-based decomposition through the Nataf distribution.
Generates first order sensitivity indices
Args:
order (int):
Polynomial order used ``orth_ttr``.
dist (Copula):
Assumed to be Nataf with independent components
samples (numpy.ndarray):
Samples used for evaluation (typically generated from ``dist``.)
vals (numpy.ndarray): Evaluations of the model for given samples.
Returns:
(numpy.ndarray):
Sensitivity indices with shape ``(len(dist),) + vals.shape[1:]``. | 3.477565 | 3.419044 | 1.017116 |
order = numpy.array(order)*numpy.ones(len(dist), dtype=int)+1
_, _, coeff1, coeff2 = chaospy.quad.generate_stieltjes(
dist, numpy.max(order), accuracy=accuracy, retall=True, **kws)
dimensions = len(dist)
abscisas, weights = _golbub_welsch(order, coeff1, coeff2)
if dimensions == 1:
abscisa = numpy.reshape(abscisas, (1, order[0]))
weight = numpy.reshape(weights, (order[0],))
else:
abscisa = chaospy.quad.combine(abscisas).T
weight = numpy.prod(chaospy.quad.combine(weights), -1)
assert len(abscisa) == dimensions
assert len(weight) == len(abscisa.T)
return abscisa, weight | def quad_golub_welsch(order, dist, accuracy=100, **kws) | Golub-Welsch algorithm for creating quadrature nodes and weights.
Args:
order (int):
Quadrature order
dist (Dist):
Distribution nodes and weights are found for with `dim=len(dist)`
accuracy (int):
Accuracy used in discretized Stieltjes procedure. Will
be increased by one for each iteration.
Returns:
(numpy.ndarray, numpy.ndarray):
Optimal collocation nodes with `x.shape=(dim, order+1)` and weights
with `w.shape=(order+1,)`.
Examples:
>>> Z = chaospy.Normal()
>>> x, w = chaospy.quad_golub_welsch(3, Z)
>>> print(numpy.around(x, 4))
[[-2.3344 -0.742 0.742 2.3344]]
>>> print(numpy.around(w, 4))
[0.0459 0.4541 0.4541 0.0459]
>>> Z = chaospy.J(chaospy.Uniform(), chaospy.Uniform())
>>> x, w = chaospy.quad_golub_welsch(1, Z)
>>> print(numpy.around(x, 4))
[[0.2113 0.2113 0.7887 0.7887]
[0.2113 0.7887 0.2113 0.7887]]
>>> print(numpy.around(w, 4))
[0.25 0.25 0.25 0.25] | 3.542701 | 3.990164 | 0.887859 |
abscisas, weights = [], []
for dim, order in enumerate(orders):
if order:
bands = numpy.zeros((2, order))
bands[0] = coeff1[dim, :order]
bands[1, :-1] = numpy.sqrt(coeff2[dim, 1:order])
vals, vecs = scipy.linalg.eig_banded(bands, lower=True)
abscisa, weight = vals.real, vecs[0, :]**2
indices = numpy.argsort(abscisa)
abscisa, weight = abscisa[indices], weight[indices]
else:
abscisa, weight = numpy.array([coeff1[dim, 0]]), numpy.array([1.])
abscisas.append(abscisa)
weights.append(weight)
return abscisas, weights | def _golbub_welsch(orders, coeff1, coeff2) | Recurrence coefficients to abscisas and weights. | 2.735854 | 2.531318 | 1.080802 |
if isinstance(left, Dist):
if left in cache:
left = cache[left]
else:
left = evaluation.evaluate_bound(left, xloc, cache=cache)
else:
left = (numpy.array(left).T * numpy.ones((2,)+xloc.shape).T).T
if isinstance(right, Dist):
if right in cache:
right = cache[right]
else:
right = evaluation.evaluate_bound(right, xloc, cache=cache)
else:
right = (numpy.array(right).T * numpy.ones((2,)+xloc.shape).T).T
return left[0], right[1] | def _bnd(self, xloc, left, right, cache) | Distribution bounds.
Example:
>>> print(chaospy.Uniform().range([-2, 0, 2, 4]))
[[0. 0. 0. 0.]
[1. 1. 1. 1.]]
>>> print(chaospy.Trunc(chaospy.Uniform(), 0.6).range([-2, 0, 2, 4]))
[[0. 0. 0. 0. ]
[0.6 0.6 0.6 0.6]]
>>> print(chaospy.Trunc(0.4, chaospy.Uniform()).range([-2, 0, 2, 4]))
[[0.4 0.4 0.4 0.4]
[1. 1. 1. 1. ]] | 2.274262 | 2.2921 | 0.992218 |
if isinstance(left, Dist) and left in cache:
left = cache[left]
if isinstance(right, Dist) and right in cache:
right = cache[right]
if isinstance(left, Dist):
if isinstance(right, Dist):
raise StochasticallyDependentError(
"under-defined distribution {} or {}".format(left, right))
else:
left = (numpy.array(left).T*numpy.ones(xloc.shape).T).T
uloc1 = evaluation.evaluate_forward(right, left, cache=cache.copy())
uloc2 = evaluation.evaluate_forward(right, xloc, cache=cache)
return (uloc2-uloc1)/(1-uloc1)
right = (numpy.array(right).T*numpy.ones(xloc.shape).T).T
uloc1 = evaluation.evaluate_forward(left, right, cache=cache.copy())
uloc2 = evaluation.evaluate_forward(left, xloc, cache=cache)
return uloc2/uloc1 | def _cdf(self, xloc, left, right, cache) | Cumulative distribution function.
Example:
>>> print(chaospy.Uniform().fwd([-0.5, 0.3, 0.7, 1.2]))
[0. 0.3 0.7 1. ]
>>> print(chaospy.Trunc(chaospy.Uniform(), 0.4).fwd([-0.5, 0.2, 0.8, 1.2]))
[0. 0.5 1. 1. ]
>>> print(chaospy.Trunc(0.6, chaospy.Uniform()).fwd([-0.5, 0.2, 0.8, 1.2]))
[0. 0. 0.5 1. ] | 2.537047 | 2.541621 | 0.9982 |
if isinstance(left, Dist) and left in cache:
left = cache[left]
if isinstance(right, Dist) and right in cache:
right = cache[right]
if isinstance(left, Dist):
if isinstance(right, Dist):
raise StochasticallyDependentError(
"under-defined distribution {} or {}".format(left, right))
elif not isinstance(right, Dist):
raise StochasticallyDependentError(
"truncated variable indirectly depends on underlying variable")
else:
left = (numpy.array(left).T*numpy.ones(q.shape).T).T
uloc = evaluation.evaluate_forward(right, left)
return evaluation.evaluate_inverse(right, q*(1-uloc)+uloc, cache=cache)
right = (numpy.array(right).T*numpy.ones(q.shape).T).T
uloc = evaluation.evaluate_forward(left, right, cache=cache.copy())
return evaluation.evaluate_inverse(left, q*uloc, cache=cache) | def _ppf(self, q, left, right, cache) | Point percentile function.
Example:
>>> print(chaospy.Uniform().inv([0.1, 0.2, 0.9]))
[0.1 0.2 0.9]
>>> print(chaospy.Trunc(chaospy.Uniform(), 0.4).inv([0.1, 0.2, 0.9]))
[0.04 0.08 0.36]
>>> print(chaospy.Trunc(0.6, chaospy.Uniform()).inv([0.1, 0.2, 0.9]))
[0.64 0.68 0.96] | 3.401288 | 3.280346 | 1.036869 |
if isinstance(poly, distributions.Dist):
x = polynomials.variable(len(poly))
poly, dist = x, poly
else:
poly = polynomials.Poly(poly)
if fisher:
adjust = 3
else:
adjust = 0
shape = poly.shape
poly = polynomials.flatten(poly)
m1 = E(poly, dist)
m2 = E(poly**2, dist)
m3 = E(poly**3, dist)
m4 = E(poly**4, dist)
out = (m4-4*m3*m1 + 6*m2*m1**2 - 3*m1**4) /\
(m2**2-2*m2*m1**2+m1**4) - adjust
out = numpy.reshape(out, shape)
return out | def Kurt(poly, dist=None, fisher=True, **kws) | Kurtosis operator.
Element by element 4rd order statistics of a distribution or polynomial.
Args:
poly (Poly, Dist):
Input to take kurtosis on.
dist (Dist):
Defines the space the skewness is taken on. It is ignored if
``poly`` is a distribution.
fisher (bool):
If True, Fisher's definition is used (Normal -> 0.0). If False,
Pearson's definition is used (normal -> 3.0)
Returns:
(numpy.ndarray):
Element for element variance along ``poly``, where
``skewness.shape==poly.shape``.
Examples:
>>> dist = chaospy.J(chaospy.Gamma(1, 1), chaospy.Normal(0, 2))
>>> print(numpy.around(chaospy.Kurt(dist), 4))
[6. 0.]
>>> print(numpy.around(chaospy.Kurt(dist, fisher=False), 4))
[9. 3.]
>>> x, y = chaospy.variable(2)
>>> poly = chaospy.Poly([1, x, y, 10*x*y])
>>> print(numpy.around(chaospy.Kurt(poly, dist), 4))
[nan 6. 0. 15.] | 3.144041 | 3.239966 | 0.970393 |
if stop is None:
start, stop = numpy.array(0), start
start = numpy.array(start, dtype=int)
stop = numpy.array(stop, dtype=int)
dim = max(start.size, stop.size, dim)
indices = numpy.array(chaospy.bertran.bindex(
numpy.min(start), 2*numpy.max(stop), dim, sort, cross_truncation))
if start.size == 1:
bellow = numpy.sum(indices, -1) >= start
else:
start = numpy.ones(dim, dtype=int)*start
bellow = numpy.all(indices-start >= 0, -1)
if stop.size == 1:
above = numpy.sum(indices, -1) <= stop.item()
else:
stop = numpy.ones(dim, dtype=int)*stop
above = numpy.all(stop-indices >= 0, -1)
pool = list(indices[above*bellow])
arg = numpy.zeros(len(pool), dtype=int)
arg[0] = 1
poly = {}
for idx in pool:
idx = tuple(idx)
poly[idx] = arg
arg = numpy.roll(arg, 1)
x = numpy.zeros(len(pool), dtype=int)
x[0] = 1
A = {}
for I in pool:
I = tuple(I)
A[I] = x
x = numpy.roll(x,1)
return Poly(A, dim) | def basis(start, stop=None, dim=1, sort="G", cross_truncation=1.) | Create an N-dimensional unit polynomial basis.
Args:
start (int, numpy.ndarray):
the minimum polynomial to include. If int is provided, set as
lowest total order. If array of int, set as lower order along each
axis.
stop (int, numpy.ndarray):
the maximum shape included. If omitted:
``stop <- start; start <- 0`` If int is provided, set as largest
total order. If array of int, set as largest order along each axis.
dim (int):
dim of the basis. Ignored if array is provided in either start or
stop.
sort (str):
The polynomial ordering where the letters ``G``, ``I`` and ``R``
can be used to set grade, inverse and reverse to the ordering. For
``basis(start=0, stop=2, dim=2, order=order)`` we get:
====== ==================
order output
====== ==================
"" [1 y y^2 x xy x^2]
"G" [1 y x y^2 xy x^2]
"I" [x^2 xy x y^2 y 1]
"R" [1 x x^2 y xy y^2]
"GIR" [y^2 xy x^2 y x 1]
====== ==================
cross_truncation (float):
Use hyperbolic cross truncation scheme to reduce the number of
terms in expansion.
Returns:
(Poly) : Polynomial array.
Examples:
>>> print(chaospy.basis(4, 4, 2))
[q0^4, q0^3q1, q0^2q1^2, q0q1^3, q1^4]
>>> print(chaospy.basis([1, 1], [2, 2]))
[q0q1, q0^2q1, q0q1^2, q0^2q1^2] | 2.988404 | 3.141381 | 0.951302 |
if len(args) == 1:
low, high = 0, args[0]
else:
low, high = args[:2]
core_old = poly.A
core_new = {}
for key in poly.keys:
if low <= numpy.sum(key) < high:
core_new[key] = core_old[key]
return Poly(core_new, poly.dim, poly.shape, poly.dtype) | def cutoff(poly, *args) | Remove polynomial components with order outside a given interval.
Args:
poly (Poly):
Input data.
low (int):
The lowest order that is allowed to be included. Defaults to 0.
high (int):
The upper threshold for the cutoff range.
Returns:
(Poly):
The same as `P`, except that all terms that have a order not within
the bound `low <= order < high` are removed.
Examples:
>>> poly = chaospy.prange(4, 1) + chaospy.prange(4, 2)[::-1]
>>> print(poly) # doctest: +SKIP
[q1^3+1, q0+q1^2, q0^2+q1, q0^3+1]
>>> print(chaospy.cutoff(poly, 3)) # doctest: +SKIP
[1, q0+q1^2, q0^2+q1, 1]
>>> print(chaospy.cutoff(poly, 1, 3)) # doctest: +SKIP
[0, q0+q1^2, q0^2+q1, 0] | 3.537257 | 3.744237 | 0.94472 |
P, Q = Poly(P), Poly(Q)
if not chaospy.poly.is_decomposed(Q):
differential(chaospy.poly.decompose(Q)).sum(0)
if Q.shape:
return Poly([differential(P, q) for q in Q])
if Q.dim>P.dim:
P = chaospy.poly.setdim(P, Q.dim)
else:
Q = chaospy.poly.setdim(Q, P.dim)
qkey = Q.keys[0]
A = {}
for key in P.keys:
newkey = numpy.array(key) - numpy.array(qkey)
if numpy.any(newkey<0):
continue
A[tuple(newkey)] = P.A[key]*numpy.prod([fac(key[i], \
exact=True)/fac(newkey[i], exact=True) \
for i in range(P.dim)])
return Poly(B, P.dim, P.shape, P.dtype) | def differential(P, Q) | Polynomial differential operator.
Args:
P (Poly):
Polynomial to be differentiated.
Q (Poly):
Polynomial to differentiate by. Must be decomposed. If polynomial
array, the output is the Jacobian matrix. | 4.384303 | 4.235562 | 1.035117 |
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