> Would it be possible to have a simple example on this new dimacs like > data format? I presumed that this new format only applies to GLPK, not > on MathProg. An example will be easy to visualise the new data format, > in my case.
This is an example model in cplex lp format: \* Problem: transp *\ Minimize cost: + 0.225 x(Seattle,New~York) + 0.153 x(Seattle,Chicago) + 0.162 x(Seattle,Topeka) + 0.225 x(San~Diego,New~York) + 0.162 x(San~Diego,Chicago) + 0.126 x(San~Diego,Topeka) Subject To supply(Seattle): + x(Seattle,New~York) + x(Seattle,Chicago) + x(Seattle,Topeka) <= 350 supply(San~Diego): + x(San~Diego,New~York) + x(San~Diego,Chicago) + x(San~Diego,Topeka) <= 600 demand(New~York): + x(Seattle,New~York) + x(San~Diego,New~York) >= 325 demand(Chicago): + x(Seattle,Chicago) + x(San~Diego,Chicago) >= 300 demand(Topeka): + x(Seattle,Topeka) + x(San~Diego,Topeka) >= 275 End The same model in glpk lp/mip (dimacs-like) format looks like the following (please note that this is a preliminary version): n transp p lp 6 6 18 z cost r 1 cost i 1 f r 2 supply[Seattle] i 2 u 350 r 3 supply[San-Diego] i 3 u 600 r 4 demand[New-York] i 4 l 325 r 5 demand[Chicago] i 5 l 300 r 6 demand[Topeka] i 6 l 275 x 1 x[Seattle,New-York] j 1 l 0 a 0 1 0.225 x 2 x[Seattle,Chicago] j 2 l 0 a 0 2 0.153 x 3 x[Seattle,Topeka] j 3 l 0 a 0 3 0.162 x 4 x[San-Diego,New-York] j 4 l 0 a 0 4 0.225 x 5 x[San-Diego,Chicago] j 5 l 0 a 0 5 0.162 x 6 x[San-Diego,Topeka] j 6 l 0 a 0 6 0.126 a 1 1 0.225 a 1 2 0.153 a 1 3 0.162 a 1 4 0.225 a 1 5 0.162 a 1 6 0.126 a 2 1 1 a 2 2 1 a 2 3 1 a 3 4 1 a 3 5 1 a 3 6 1 a 4 1 1 a 4 4 1 a 5 2 1 a 5 5 1 a 6 3 1 a 6 6 1 c eof _______________________________________________ Help-glpk mailing list [email protected] http://lists.gnu.org/mailman/listinfo/help-glpk
