FUNCTION: uf_editedge - edit edges of a unit form

CALLING SEQUENCE:
uf_editedge(q,i,j,k)

PARAMETERS:
q - matrix of the unit form
i,j - vertices
k - new edge between vertices i and j

SYNOPSIS:

• uf_editedge changes edges between two vertices.

EXAMPLES:

> q:=uf_init([3,[1,2],[2,3],[3,1]]);

> uf_type(q);

> q:=uf_editedge(q,1,2,1);

> uf_type(q);