Replace 'is' with == or similar.

Related to issue #113, but I did not touch
persistence_graphical_tools.py which is handled in PR #119.
I don't know if I got them all, I guess we'll start seeing the warnings
with python-3.8 soon enough.

9 files changed, 18 insertions, 18 deletions

diff --git a/src/python/gudhi/euclidean_strong_witness_complex.pyx b/src/python/gudhi/euclidean_strong_witness_complex.pyx
index 5d6e4fb9..0e5b544a 100644
--- a/src/python/gudhi/euclidean_strong_witness_complex.pyx
+++ b/src/python/gudhi/euclidean_strong_witness_complex.pyx
@@ -71,7 +71,7 @@ cdef class EuclideanStrongWitnessComplex:
         """
         stree = SimplexTree()
         cdef intptr_t stree_int_ptr=stree.thisptr
-        if limit_dimension is not -1:
+        if limit_dimension != -1:
             self.thisptr.create_simplex_tree(<Simplex_tree_interface_full_featured*>stree_int_ptr,
                 max_alpha_square, limit_dimension)
         else:
diff --git a/src/python/gudhi/euclidean_witness_complex.pyx b/src/python/gudhi/euclidean_witness_complex.pyx
index 2531919b..86d2d996 100644
--- a/src/python/gudhi/euclidean_witness_complex.pyx
+++ b/src/python/gudhi/euclidean_witness_complex.pyx
@@ -71,7 +71,7 @@ cdef class EuclideanWitnessComplex:
         """
         stree = SimplexTree()
         cdef intptr_t stree_int_ptr=stree.thisptr
-        if limit_dimension is not -1:
+        if limit_dimension != -1:
             self.thisptr.create_simplex_tree(<Simplex_tree_interface_full_featured*>stree_int_ptr,
                 max_alpha_square, limit_dimension)
         else:
diff --git a/src/python/gudhi/off_reader.pyx b/src/python/gudhi/off_reader.pyx
index 9efd97ff..27a89870 100644
--- a/src/python/gudhi/off_reader.pyx
+++ b/src/python/gudhi/off_reader.pyx
@@ -29,7 +29,7 @@ def read_off(off_file=''):
     :returns:  The point set.
     :rtype: vector[vector[double]]
     """
-    if off_file is not '':
+    if off_file:
         if os.path.isfile(off_file):
             return read_points_from_OFF_file(str.encode(off_file))
         else:
diff --git a/src/python/gudhi/periodic_cubical_complex.pyx b/src/python/gudhi/periodic_cubical_complex.pyx
index 724fadd4..88223afb 100644
--- a/src/python/gudhi/periodic_cubical_complex.pyx
+++ b/src/python/gudhi/periodic_cubical_complex.pyx
@@ -68,9 +68,9 @@ cdef class PeriodicCubicalComplex:
     # The real cython constructor
     def __cinit__(self, dimensions=None, top_dimensional_cells=None,
                   periodic_dimensions=None, perseus_file=''):
-        if (dimensions is not None) and (top_dimensional_cells is not None) and (periodic_dimensions is not None) and (perseus_file is ''):
+        if (dimensions is not None) and (top_dimensional_cells is not None) and (periodic_dimensions is not None) and (perseus_file == ''):
             self.thisptr = new Periodic_cubical_complex_base_interface(dimensions, top_dimensional_cells, periodic_dimensions)
-        elif (dimensions is None) and (top_dimensional_cells is None) and (periodic_dimensions is None) and (perseus_file is not ''):
+        elif (dimensions is None) and (top_dimensional_cells is None) and (periodic_dimensions is None) and (perseus_file != ''):
             if os.path.isfile(perseus_file):
                 self.thisptr = new Periodic_cubical_complex_base_interface(str.encode(perseus_file))
             else:
diff --git a/src/python/gudhi/reader_utils.pyx b/src/python/gudhi/reader_utils.pyx
index 147fae71..b266c783 100644
--- a/src/python/gudhi/reader_utils.pyx
+++ b/src/python/gudhi/reader_utils.pyx
@@ -37,7 +37,7 @@ def read_lower_triangular_matrix_from_csv_file(csv_file='', separator=';'):
     :returns:  The lower triangular matrix.
     :rtype: vector[vector[double]]
     """
-    if csv_file is not '':
+    if csv_file:
         if path.isfile(csv_file):
             return read_matrix_from_csv_file(str.encode(csv_file), ord(separator[0]))
     print("file " + csv_file + " not set or not found.")
@@ -56,7 +56,7 @@ def read_persistence_intervals_grouped_by_dimension(persistence_file=''):
     :returns:  The persistence pairs grouped by dimension.
     :rtype: map[int, vector[pair[double, double]]]
     """
-    if persistence_file is not '':
+    if persistence_file:
         if path.isfile(persistence_file):
             return read_pers_intervals_grouped_by_dimension(str.encode(persistence_file))
     print("file " + persistence_file + " not set or not found.")
@@ -79,7 +79,7 @@ def read_persistence_intervals_in_dimension(persistence_file='', only_this_dim=-
     :returns:  The persistence intervals.
     :rtype: numpy array of dimension 2
     """
-    if persistence_file is not '':
+    if persistence_file:
         if path.isfile(persistence_file):
             return np_array(read_pers_intervals_in_dimension(str.encode(
                 persistence_file), only_this_dim))
diff --git a/src/python/gudhi/strong_witness_complex.pyx b/src/python/gudhi/strong_witness_complex.pyx
index e757abea..e35ba6ad 100644
--- a/src/python/gudhi/strong_witness_complex.pyx
+++ b/src/python/gudhi/strong_witness_complex.pyx
@@ -69,7 +69,7 @@ cdef class StrongWitnessComplex:
         """
         stree = SimplexTree()
         cdef intptr_t stree_int_ptr=stree.thisptr
-        if limit_dimension is not -1:
+        if limit_dimension != -1:
             self.thisptr.create_simplex_tree(<Simplex_tree_interface_full_featured*>stree_int_ptr,
                 max_alpha_square, limit_dimension)
         else:
diff --git a/src/python/gudhi/subsampling.pyx b/src/python/gudhi/subsampling.pyx
index 1135c1fb..e622ac99 100644
--- a/src/python/gudhi/subsampling.pyx
+++ b/src/python/gudhi/subsampling.pyx
@@ -44,15 +44,15 @@ def choose_n_farthest_points(points=None, off_file='', nb_points=0, starting_poi
     :param nb_points: Number of points of the subsample.
     :type nb_points: unsigned.
     :param starting_point: The iteration starts with the landmark `starting \
-    point`,which is the index of the poit to start with. If not set, this \
-    index is choosen randomly.
+    point`,which is the index of the point to start with. If not set, this \
+    index is chosen randomly.
     :type starting_point: unsigned.
     :returns:  The subsample point set.
     :rtype: vector[vector[double]]
     """
-    if off_file is not '':
+    if off_file:
         if os.path.isfile(off_file):
-            if starting_point is '':
+            if starting_point == '':
                 return subsampling_n_farthest_points_from_file(str.encode(off_file),
                                                                nb_points)
             else:
@@ -65,7 +65,7 @@ def choose_n_farthest_points(points=None, off_file='', nb_points=0, starting_poi
         if points is None:
             # Empty points
             points=[]
-        if starting_point is '':
+        if starting_point == '':
             return subsampling_n_farthest_points(points, nb_points)
         else:
             return subsampling_n_farthest_points(points, nb_points,
@@ -87,7 +87,7 @@ def pick_n_random_points(points=None, off_file='', nb_points=0):
     :returns:  The subsample point set.
     :rtype: vector[vector[double]]
     """
-    if off_file is not '':
+    if off_file:
         if os.path.isfile(off_file):
             return subsampling_n_random_points_from_file(str.encode(off_file),
                 nb_points)
@@ -117,7 +117,7 @@ def sparsify_point_set(points=None, off_file='', min_squared_dist=0.0):
     :returns:  The subsample point set.
     :rtype: vector[vector[double]]
     """
-    if off_file is not '':
+    if off_file:
         if os.path.isfile(off_file):
             return subsampling_sparsify_points_from_file(str.encode(off_file),
                                                          min_squared_dist)
diff --git a/src/python/gudhi/tangential_complex.pyx b/src/python/gudhi/tangential_complex.pyx
index 3a945fe2..9ef15567 100644
--- a/src/python/gudhi/tangential_complex.pyx
+++ b/src/python/gudhi/tangential_complex.pyx
@@ -65,7 +65,7 @@ cdef class TangentialComplex:
 
     # The real cython constructor
     def __cinit__(self, intrisic_dim, points=None, off_file=''):
-        if off_file is not '':
+        if off_file:
             if os.path.isfile(off_file):
                 self.thisptr = new Tangential_complex_interface(intrisic_dim, str.encode(off_file), True)
             else:
diff --git a/src/python/gudhi/witness_complex.pyx b/src/python/gudhi/witness_complex.pyx
index baa70b7a..c19ccf2b 100644
--- a/src/python/gudhi/witness_complex.pyx
+++ b/src/python/gudhi/witness_complex.pyx
@@ -69,7 +69,7 @@ cdef class WitnessComplex:
         """
         stree = SimplexTree()
         cdef intptr_t stree_int_ptr=stree.thisptr
-        if limit_dimension is not -1:
+        if limit_dimension != -1:
             self.thisptr.create_simplex_tree(<Simplex_tree_interface_full_featured*>stree_int_ptr,
                 max_alpha_square, limit_dimension)
         else: