From 88a36ffad6c11279990c1c96df32b95c1f6f526c Mon Sep 17 00:00:00 2001 From: ROUVREAU Vincent Date: Fri, 3 Jul 2020 13:57:49 +0200 Subject: A fix proposal for boudaries of a simplex python version --- src/python/gudhi/simplex_tree.pxd | 8 ++++++++ src/python/gudhi/simplex_tree.pyx | 16 ++++++++++++++++ src/python/include/Simplex_tree_interface.h | 11 +++++++++++ src/python/test/test_simplex_tree.py | 9 +++++++++ 4 files changed, 44 insertions(+) (limited to 'src/python') diff --git a/src/python/gudhi/simplex_tree.pxd b/src/python/gudhi/simplex_tree.pxd index e748ac40..a64599e7 100644 --- a/src/python/gudhi/simplex_tree.pxd +++ b/src/python/gudhi/simplex_tree.pxd @@ -36,6 +36,12 @@ cdef extern from "Simplex_tree_interface.h" namespace "Gudhi": Simplex_tree_skeleton_iterator operator++() nogil bint operator!=(Simplex_tree_skeleton_iterator) nogil + cdef cppclass Simplex_tree_boundary_iterator "Gudhi::Simplex_tree_interface::Boundary_simplex_iterator": + Simplex_tree_boundary_iterator() nogil + Simplex_tree_simplex_handle& operator*() nogil + Simplex_tree_boundary_iterator operator++() nogil + bint operator!=(Simplex_tree_boundary_iterator) nogil + cdef cppclass Simplex_tree_interface_full_featured "Gudhi::Simplex_tree_interface": Simplex_tree() nogil @@ -65,6 +71,8 @@ cdef extern from "Simplex_tree_interface.h" namespace "Gudhi": vector[Simplex_tree_simplex_handle].const_iterator get_filtration_iterator_end() nogil Simplex_tree_skeleton_iterator get_skeleton_iterator_begin(int dimension) nogil Simplex_tree_skeleton_iterator get_skeleton_iterator_end(int dimension) nogil + Simplex_tree_boundary_iterator get_boundary_iterator_begin(vector[int] simplex) nogil + Simplex_tree_boundary_iterator get_boundary_iterator_end(vector[int] simplex) nogil cdef extern from "Persistent_cohomology_interface.h" namespace "Gudhi": cdef cppclass Simplex_tree_persistence_interface "Gudhi::Persistent_cohomology_interface>": diff --git a/src/python/gudhi/simplex_tree.pyx b/src/python/gudhi/simplex_tree.pyx index 20e66d9f..da445a12 100644 --- a/src/python/gudhi/simplex_tree.pyx +++ b/src/python/gudhi/simplex_tree.pyx @@ -285,6 +285,22 @@ cdef class SimplexTree: ct.append((v, filtered_simplex.second)) return ct + def get_boundaries(self, simplex): + """This function returns a generator with the boundaries of a given N-simplex. + + :param simplex: The N-simplex, represented by a list of vertex. + :type simplex: list of int. + :returns: The (simplices of the) boundaries of a simplex + :rtype: generator with tuples(simplex, filtration) + """ + cdef Simplex_tree_boundary_iterator it = self.get_ptr().get_boundary_iterator_begin(simplex) + cdef Simplex_tree_boundary_iterator end = self.get_ptr().get_boundary_iterator_end(simplex) + + while it != end: + yield self.get_ptr().get_simplex_and_filtration(dereference(it)) + preincrement(it) + + def remove_maximal_simplex(self, simplex): """This function removes a given maximal N-simplex from the simplicial complex. diff --git a/src/python/include/Simplex_tree_interface.h b/src/python/include/Simplex_tree_interface.h index 56d7c41d..c4f18eeb 100644 --- a/src/python/include/Simplex_tree_interface.h +++ b/src/python/include/Simplex_tree_interface.h @@ -36,6 +36,7 @@ class Simplex_tree_interface : public Simplex_tree { using Skeleton_simplex_iterator = typename Base::Skeleton_simplex_iterator; using Complex_simplex_iterator = typename Base::Complex_simplex_iterator; using Extended_filtration_data = typename Base::Extended_filtration_data; + using Boundary_simplex_iterator = typename Base::Boundary_simplex_iterator; public: @@ -188,6 +189,16 @@ class Simplex_tree_interface : public Simplex_tree { // this specific case works because the range is just a pair of iterators - won't work if range was a vector return Base::skeleton_simplex_range(dimension).end(); } + + Boundary_simplex_iterator get_boundary_iterator_begin(const Simplex& simplex) { + // this specific case works because the range is just a pair of iterators - won't work if range was a vector + return Base::boundary_simplex_range(Base::find(simplex)).begin(); + } + + Boundary_simplex_iterator get_boundary_iterator_end(const Simplex& simplex) { + // this specific case works because the range is just a pair of iterators - won't work if range was a vector + return Base::boundary_simplex_range(Base::find(simplex)).end(); + } }; } // namespace Gudhi diff --git a/src/python/test/test_simplex_tree.py b/src/python/test/test_simplex_tree.py index 2137d822..7c49cb1a 100755 --- a/src/python/test/test_simplex_tree.py +++ b/src/python/test/test_simplex_tree.py @@ -340,3 +340,12 @@ def test_simplices_iterator(): assert st.find(simplex[0]) == True print("filtration is: ", simplex[1]) assert st.filtration(simplex[0]) == simplex[1] + +def test_boundaries_iterator(): + st = SimplexTree() + + assert st.insert([0, 1, 2, 3], filtration=1.0) == True + assert st.insert([1, 2, 3, 4], filtration=2.0) == True + + assert list(st.get_boundaries([1, 2, 3])) == [([1, 2], 1.0), ([1, 3], 1.0), ([2, 3], 1.0)] + assert list(st.get_boundaries([2, 3, 4])) == [([2, 3], 1.0), ([2, 4], 2.0), ([3, 4], 2.0)] -- cgit v1.2.3