Andrew Makhorin wrote: > >> var sx{a in A, b in B}, binary; >> /* sx[a,b] is sign(sum{c in C} x[a,b,c]) */ >> /* in other word, sx[a,b] is logical_or{c in C} x[a,b,c] */ >> >> s.t. foo{a in A, b in B}: sum{c in C} x[a,b,c] <= card(C) * sx[a,b]; >> >> s.t. rooms{a in A}: sum{b in B} sx[a,b] <= r; > > Incorrect. The first constraint must be the following: > > s.t. foo{a in A, b in B}: > 0 <= card(C) * sx[a,b] - sum{c in C} x[a,b,c] <= card(C) - 1; > >
Thanks you really helped me out, it worked like a charm. I gotta say, the way you transformed this problem and solved it with your 0 <= card(C) * sx[a,b] - sum{c in C} x[a,b,c] <= card(C) - 1; equation is just genius and an amazing idea. You sure are a very intellgent person. You have my deepest respect and appreciation. Thanks again. -- View this message in context: http://www.nabble.com/Sign-of-an-integer-tp16535546p16537941.html Sent from the Gnu - GLPK - Help mailing list archive at Nabble.com. _______________________________________________ Help-glpk mailing list Help-glpk@gnu.org http://lists.gnu.org/mailman/listinfo/help-glpk