Fixed dtype to threshold arg

lungtumormask/__main__.py

@@ -14,7 +14,7 @@ def main():
     parser.add_argument('input', metavar='input', type=path, help='Path to the input image, should be .nifti')
     parser.add_argument('output', metavar='output', type=str, help='Filepath for output tumormask')
     parser.add_argument('--lung-filter', action='store_true', help='whether to apply lungmask postprocessing.')
-    parser.add_argument('--threshold', metavar='threshold', type=int, default=0.4, 
+    parser.add_argument('--threshold', metavar='threshold', type=float, default=0.4, 
                         help='which threshold to use for assigning voxel-wise classes.')
 
     argsin = sys.argv[1:]