From 40ca49a254b09c7ddba5ed7dbb9b0878fc70afb1 Mon Sep 17 00:00:00 2001 From: Marc Glisse Date: Thu, 24 Mar 2022 21:24:53 +0100 Subject: Rewrite python doc --- src/python/gudhi/simplex_tree.pyx | 12 +++++++----- 1 file changed, 7 insertions(+), 5 deletions(-) (limited to 'src') diff --git a/src/python/gudhi/simplex_tree.pyx b/src/python/gudhi/simplex_tree.pyx index b9c2a42f..3d7c28b6 100644 --- a/src/python/gudhi/simplex_tree.pyx +++ b/src/python/gudhi/simplex_tree.pyx @@ -621,12 +621,14 @@ cdef class SimplexTree: return (normal0, normals, infinite0, infinites) def collapse_edges(self, nb_iterations = 1): - """Assuming the simplex tree is a 1-skeleton graph, this method collapse edges (simplices of higher dimension - are ignored) and resets the simplex tree from the remaining edges. - A good candidate is to build a simplex tree on top of a :class:`~gudhi.RipsComplex` of dimension 1 before - collapsing edges + """Assuming the complex is a graph (simplices of higher dimension are ignored), this method implicitly + interprets it as the 1-skeleton of a flag complex, and replaces it with another (smaller) graph whose + expansion has the same persistent homology, using a technique known as edge collapses + (see :cite:`edgecollapsearxiv`). + + A natural application is to get a simplex tree of dimension 1 from :class:`~gudhi.RipsComplex`, + then collapse edges, perform :meth:`expansion()` and finally compute persistence (cf. :download:`rips_complex_edge_collapse_example.py <../example/rips_complex_edge_collapse_example.py>`). - For implementation details, please refer to :cite:`edgecollapsesocg2020`. :param nb_iterations: The number of edge collapse iterations to perform. Default is 1. :type nb_iterations: int -- cgit v1.2.3