Perl module to draw Graph object as a DSM matrix

 Graph::Writer::DSM writes Graph object as a quadractic matrix N x N, where N
 is the number of vertices in the graph. It uses Gnuplot and is useful to
 visualize graphs with huge number of vertices, graphs with 1k vertices for
 example.
 .
 See more about DSM: http://en.wikipedia.org/wiki/Design_structure_matrix