Add simplex tree equality operator to be able to test alpha complex

4 files changed, 59 insertions, 0 deletions

diff --git a/src/python/gudhi/simplex_tree.pxd b/src/python/gudhi/simplex_tree.pxd
index 000323af..2aa435b1 100644
--- a/src/python/gudhi/simplex_tree.pxd
+++ b/src/python/gudhi/simplex_tree.pxd
@@ -74,6 +74,7 @@ cdef extern from "Simplex_tree_interface.h" namespace "Gudhi":
         Simplex_tree_skeleton_iterator get_skeleton_iterator_begin(int dimension) nogil
         Simplex_tree_skeleton_iterator get_skeleton_iterator_end(int dimension) nogil
         pair[Simplex_tree_boundary_iterator, Simplex_tree_boundary_iterator] get_boundary_iterators(vector[int] simplex) nogil except +
+        bint operator==(Simplex_tree_interface_full_featured) nogil
 
 cdef extern from "Persistent_cohomology_interface.h" namespace "Gudhi":
     cdef cppclass Simplex_tree_persistence_interface "Gudhi::Persistent_cohomology_interface<Gudhi::Simplex_tree<Gudhi::Simplex_tree_options_full_featured>>":
diff --git a/src/python/gudhi/simplex_tree.pyx b/src/python/gudhi/simplex_tree.pyx
index d7991417..b5a938d5 100644
--- a/src/python/gudhi/simplex_tree.pyx
+++ b/src/python/gudhi/simplex_tree.pyx
@@ -639,3 +639,12 @@ cdef class SimplexTree:
             self.thisptr = <intptr_t>(ptr.collapse_edges(nb_iter))
             # Delete old pointer
             del ptr
+
+    def __eq__(self, other):
+        """Simplex tree equality operator using C++ depth first search operator==
+
+        :returns: True if the 2 simplex trees are equal, False otherwise.
+        :rtype: bool
+        """
+        cdef intptr_t other_int_ptr=other.thisptr
+        return dereference(self.get_ptr()) == dereference(<Simplex_tree_interface_full_featured*>other_int_ptr)
\ No newline at end of file
diff --git a/src/python/test/test_alpha_complex.py b/src/python/test/test_alpha_complex.py
index 35059339..a0de46c3 100755
--- a/src/python/test/test_alpha_complex.py
+++ b/src/python/test/test_alpha_complex.py
@@ -316,3 +316,40 @@ def test_inconsistency_off_weight_file():
     with pytest.raises(ValueError):
         alpha = gd.AlphaComplex(off_file="alphacomplexdoc.off",
                                 weights=[1., 2., 3., 4., 5., 6.])
+
+def _with_or_without_weight_file(precision):
+    off_file = open("weightalphacomplex.off", "w")
+    off_file.write("OFF         \n" \
+                   "5 0 0       \n" \
+                   "1. -1. -1.  \n" \
+                   "-1. 1. -1.  \n" \
+                   "-1. -1. 1.  \n" \
+                   "1. 1. 1.    \n" \
+                   "2. 2. 2.")
+    off_file.close()
+
+    weight_file = open("weightalphacomplex.wgt", "w")
+    weight_file.write("4.0\n" \
+                      "4.0\n" \
+                      "4.0\n" \
+                      "4.0\n" \
+                      "1.0\n" )
+    weight_file.close()
+
+    stree_from_files =  gd.AlphaComplex(off_file="weightalphacomplex.off",
+                                        weight_file="weightalphacomplex.wgt",
+                                        precision = precision).create_simplex_tree()
+
+    stree_from_values = gd.AlphaComplex(points=[[ 1., -1., -1.],
+                                                [-1.,  1., -1.],
+                                                [-1., -1.,  1.],
+                                                [ 1.,  1.,  1.],
+                                                [ 2.,  2.,  2.]],
+                                        weights = [4., 4., 4., 4., 1.],
+                                        precision = precision).create_simplex_tree()
+
+    assert stree_from_files == stree_from_values
+
+def test_with_or_without_weight_file():
+    for precision in ['fast', 'safe', 'exact']:
+        _with_or_without_weight_file(precision)
diff --git a/src/python/test/test_simplex_tree.py b/src/python/test/test_simplex_tree.py
index a3eacaa9..83b5c268 100755
--- a/src/python/test/test_simplex_tree.py
+++ b/src/python/test/test_simplex_tree.py
@@ -404,3 +404,15 @@ def test_boundaries_iterator():
 
     with pytest.raises(RuntimeError):
         list(st.get_boundaries([6])) # (6) does not exist
+
+def test_equality_operator():
+    st1 = SimplexTree()
+    st2 = SimplexTree()
+
+    assert st1 == st2
+
+    st1.insert([1,2,3], 4.)
+    assert st1 != st2
+
+    st2.insert([1,2,3], 4.)
+    assert st1 == st2