some python3 specifics

tfields/bases/manifold_3.py

@@ -129,7 +129,12 @@ def cartesian_to_spherical(array):
     # phi for phi between -pi, pi
     problemPhiIndices = np.where((array[:, 0] < 0) & (array[:, 1] == 0))
     with warnings.catch_warnings():
-        warnings.filterwarnings('ignore', message="invalid value encountered in divide")
+        # python2.7
+        warnings.filterwarnings('ignore',
+                                message="invalid value encountered in divide")
+        # python3.x
+        warnings.filterwarnings('ignore',
+                                message="invalid value encountered in true_divide")
         array[:, 1] = np.sign(array[:, 1]) * np.arccos(array[:, 0] / np.sqrt(xy))
     array[:, 1][problemPhiIndices] = np.pi
 

tfields/core.py

@@ -183,7 +183,7 @@ class AbstractNdarray(np.ndarray):
         inst = super(AbstractNdarray, self).copy(*args, **kwargs)
         for attr in self._iter_slots():
             value = getattr(self, attr)
-            if hasattr(value, 'copy'):
+            if hasattr(value, 'copy') and not isinstance(value, list):
                 setattr(inst, attr, value.copy(*args, **kwargs))
             elif isinstance(value, list):
                 list_copy = []
@@ -307,7 +307,7 @@ class AbstractNdarray(np.ndarray):
                         part_dict = part._as_dict()
                         for part_attr, part_value in part_dict.items():
                             d["{attr}::{i}::{part_attr}".format(**locals())] = part_value
-                continue
+                    continue
             if isinstance(value, AbstractNdarray):
                 value = value._as_dict()
             d[attr] = value
@@ -1763,9 +1763,7 @@ class TensorMaps(TensorFields):
         keep_indices = indices[mask]
         if isinstance(keep_indices, int):
             keep_indices = [keep_indices]
-        delete_indices = set(indices).difference(set(keep_indices))
-        # delete_indices = indices[~mask]
-        # delete_indices = set(delete_indices)  # set speeds up everything enormously
+        delete_indices = set(indices.flat).difference(set(keep_indices.flat))
 
         masks = []
         for mp_idx in range(len(self.maps)):
@@ -1834,5 +1832,5 @@ class TensorMaps(TensorFields):
 if __name__ == '__main__':  # pragma: no cover
     import doctest
     doctest.testmod()
-    # doctest.run_docstring_examples(TensorFields.__getitem__, globals())
+    # doctest.run_docstring_examples(TensorMaps.cut, globals())
     # doctest.run_docstring_examples(AbstractNdarray._save_npz, globals())

tfields/lib/grid.py

 import numpy as np
+import functools
 
 
 def ensure_complex(*base_vectors):
@@ -95,8 +96,8 @@ def igrid(*base_vectors, **kwargs):
     else:
         base_vectors = to_base_vectors(*base_vectors)
 
-        obj = np.empty(shape=(reduce(lambda x, y: x * y,
-                                     map(len, base_vectors)),
+        obj = np.empty(shape=(functools.reduce(lambda x, y: x * y,
+                                               map(len, base_vectors)),
                               len(base_vectors)))
 
         def loop_rec(y, n_max, i=0, n=None, *vals):

tfields/mesh3D.py

@@ -508,7 +508,7 @@ class Mesh3D(tfields.TensorMaps):
                                     # new vertex
                                     new_face.append(len(vertices))
                                     vertices = np.append(vertices,
-                                                         [map(float, item)],
+                                                         [[float(x) for x in item]],
                                                          axis=0)
                                     fields = [np.append(field,
                                                         np.full((1,) + field.shape[1:], np.nan),
@@ -649,6 +649,7 @@ class Mesh3D(tfields.TensorMaps):
                             to redo the same cut fast
         Examples:
             define the cut
+            >>> import numpy as np
             >>> import tfields
             >>> from sympy.abc import x,y,z
             >>> cutExpr = x > 1.5

tfields/triangles3D.py

@@ -407,8 +407,12 @@ class Triangles3D(tfields.TensorFields):
         # matrix vector product for matrices and vectors
         barCoords = np.einsum('...ji,...i', self._baricentric_matrix, ap)
         with warnings.catch_warnings():
+            # python2.7
             warnings.filterwarnings('ignore', message="invalid value encountered in divide")
             warnings.filterwarnings('ignore', message="divide by zero encountered in divide")
+            # python3.x
+            warnings.filterwarnings('ignore', message="invalid value encountered in true_divide")
+            warnings.filterwarnings('ignore', message="divide by zero encountered in true_divide")
             barCoords[:, 2] /= delta  # allow devide by 0.
         return barCoords