simplices: Vertices and simplices af a simplicial complex object

In corybrunson/sc: Create an 'igraph' Subclass to Encode Simplicial Complexes

Description

These functions return the vertices and the simplices of an object of class 'sc'.

Usage

sc_vertices(sc, simplices = NULL)

sc_simplices(sc, vertices = NULL)

sc_faces(sc, vertices = NULL)

sc_has_simplex(sc, ...)

sc_simplex(sc, ...)

sc_intersection(sc, ...)

sc_nearness(sc, ...)

Arguments

sc	Bipartite igraph::igraph object, representing a simplicial complex.
vertices, simplices	Numeric vertex IDs or character names of nodes of sc whose incident nodes are desired (if any). Defaults to NULL.
...	Integer, character, or 'igraph.vs' used to identify nodes of sc corresponding to vertices or simplices, as appropriate.

Details

sc encodes simplicial complexes as bipartite igraph::igraph objects prefixed with a new 'sc' class, whose nodes are partitioned into those encoding the vertices versus defining simplices of the complex. The simplices are taken to be these defining simplicies together with all of their faces (sub-simplices).

The "type" attribute takes the values FALSE on the vertex nodes and TRUE on the simplex nodes. The functions sc_vertices() and sc_simplices() return the nodes of the 'sc' object corresponding to the vertices and to the simplices, respectively. To obtain the vertices in a specific set of simplices or the simplices containing a specific set of vertices, pass the indices of these simplices or vertices to the corresponding arguments.

Examples

# load data
data(wiki_sc)
# inspection and visualization
print(wiki_sc)
plot(wiki_sc, vertex.label = NA)
# vertices and simplices
sc_vertices(wiki_sc)
sc_simplices(wiki_sc)
sc_vertices(wiki_sc, simplices = letters[1:3])
sc_simplices(wiki_sc, vertices = 1:5)

corybrunson/sc documentation built on Aug. 27, 2019, 1:12 p.m.