Toplex Map

Classes
class	Gudhi::Lazy_toplex_map
	Lazy toplex map data structure for representing unfiltered simplicial complexes. More...
class	Gudhi::Toplex_map
	Toplex map data structure for representing unfiltered simplicial complexes. More...

Detailed Description

Author

François Godi

Definition

A Toplex_map is a data structure to represent and store a simplicial complex. A "toplex" is the contraction of "top-simplex", also known as a maximal simplex. The plural form of "toplex" will be called "toplices".

Let's consider a simplicial complex, denote by \(d\) its dimension and by \(k\) its number of maximal simplices. Furthermore, denote by \(\Gamma_0\) the maximal number of toplices, i.e. maximal simplices, that contain a same vertex.

The goal of the Toplex Map is both to represent the complex in optimal O(kd) space and to provide fast standard operations such as : insertion, removal, contraction of an edge, collapses and membership of a simplex. The time needed for these operation is linear or quadratic in \(\Gamma_0\) and \(d\).

Toplex map is composed firstly of a raw storage of toplices and secondly of a map which associate any vertex to a set of pointers toward all toplices containing this vertex. The data structure is described in [9] (aka. Simplex Array List or SAL).

The performances are a lot better than the Simplex_tree as soon you use maximal simplices and not simplices (cf. [5] ).