[Help-glpk] Re: constraint matrix visualization

[Andrew Makhorin]

>> Do you mean viewing the matrix pattern? Or what?

> Yes, matrix pattern produced by running mathprog script / model.

The text file in glpk lp/mip format produced by 'glpsol --wglp'
among other things contains the constraint matrix in coordinate
format. The matrix can be easily extracted (for example, with a gawk
script) and converted to a data file for gnuplot or a similar utility.