R igraph manual pages

Use this if you are using igraph from R

All isomorphic mappings between a graph and subgraphs of another graph

Description

All isomorphic mappings between a graph and subgraphs of another graph

Usage

```subgraph_isomorphisms(pattern, target, method = c("lad", "vf2"), ...)
```

Arguments

 `pattern` The smaller graph, it might be directed or undirected. Undirected graphs are treated as directed graphs with mutual edges. `target` The bigger graph, it might be directed or undirected. Undirected graphs are treated as directed graphs with mutual edges. `method` The method to use. Possible values: ‘auto’, ‘lad’, ‘vf2’. See their details below. `...` Additional arguments, passed to the various methods.

Value

A list of vertex sequences, corresponding to all mappings from the first graph to the second.

This is the LAD algorithm by Solnon, see the reference below. It has the following extra arguments:

domains

If not `NULL`, then it specifies matching restrictions. It must be a list of `target` vertex sets, given as numeric vertex ids or symbolic vertex names. The length of the list must be `vcount(pattern)` and for each vertex in `pattern` it gives the allowed matching vertices in `target`. Defaults to `NULL`.

induced

Logical scalar, whether to search for an induced subgraph. It is `FALSE` by default.

time.limit

The processor time limit for the computation, in seconds. It defaults to `Inf`, which means no limit.

‘vf2’ method

This method uses the VF2 algorithm by Cordella, Foggia et al., see references below. It supports vertex and edge colors and have the following extra arguments:

vertex.color1, vertex.color2

Optional integer vectors giving the colors of the vertices for colored graph isomorphism. If they are not given, but the graph has a “color” vertex attribute, then it will be used. If you want to ignore these attributes, then supply `NULL` for both of these arguments. See also examples below.

edge.color1, edge.color2

Optional integer vectors giving the colors of the edges for edge-colored (sub)graph isomorphism. If they are not given, but the graph has a “color” edge attribute, then it will be used. If you want to ignore these attributes, then supply `NULL` for both of these arguments.

Other graph isomorphism: `count_isomorphisms`, `count_subgraph_isomorphisms`, `graph_from_isomorphism_class`, `isomorphic`, `isomorphism_class`, `isomorphisms`, `subgraph_isomorphic`