# [Xy-pic] How to identify vertices.

**Florent Madelaine
**
florent.madelaine@univ-reunion.fr

*Mon, 10 Jun 2002 14:22:21 +0200*

I need to draw some graphs. However, since they are composed mostly of
oriented cycles, I decided to use the polygon feature, hence getting a
nicer display than with the graph package.
I need to consider homomorphic images of such oriented cycles; for
example consider a 3-cycle and a 5-cycle with one common vertex. Is
there an easy way of doing this with the polygon package ? (as the
reference point of a polygon is its center and not one of its point, I
don't really know how to move one polygon, say "tri" such that the
vertex "tri2" is identified with the vertex of some other polygon, say
"Penbta5"...).
cheers,
Florent.