Construct the incidence structure D corresponding to the graph G, where the blocks of D correspond to the edges of G.

The point graph G of the incidence structure D. The graph G has the same point set as D and two vertices u and v of G are adjacent whenever there is a block of D containing both u and v.

The block graph of the incidence structure D, i.e. the point graph of the dual of D.

The incidence graph of the incidence structure D. This bipartite graph has as vertex set the union of the point set P and block set B of D. A vertex p in P is adjacent to a vertex b in B whenever p in b.

Given an incidence structure D with v points and a finite field K, this function returns the linear code C of length v generated by the characteristic functions of the blocks of D considered as vectors of the K-space K^((v)).

> D := WittDesign(24);
> C := LinearCode(D, GF(2));
> C eq GolayCode(GF(2), true);
true