Can I get a relaxed value when I write the following code under my model? I do not have any decision variable results when I do it. Do I need to change anything?
main {
var status = 0;
thisOplModel.generate();
if (cplex.solve()) {
writeln("Integer Model");
writeln("OBJECTIVE: ",cplex.getObjValue());
if (cplex.getObjValue() != 1) {
status = -1;
}
}
thisOplModel.convertAllIntVars();
if (cplex.solve()) {
writeln("Relaxed Model");
writeln("OBJECTIVE: ",cplex.getObjValue());
if (cplex.getObjValue() != 0.5) {
status = -1;
}
}
(status);
}
sure.
Full example from Relax integrity constraints and dual value in Making Optimization Simple
int nbKids=300;
float costBus40=500;
float costBus30=400;
dvar int+ nbBus40;
dvar int+ nbBus30;
minimize
costBus40*nbBus40 +nbBus30*costBus30;
subject to
{
ctKids:40*nbBus40+nbBus30*30>=nbKids;
}
main {
var status = 0;
thisOplModel.generate();
if (cplex.solve()) {
writeln("Integer Model");
writeln("OBJECTIVE: ",cplex.getObjValue());
}
// relax integrity constraint
thisOplModel.convertAllIntVars();
if (cplex.solve()) {
writeln("Relaxed Model");
writeln("OBJECTIVE: ",cplex.getObjValue());
writeln("dual of the kids constraint = ",thisOplModel.ctKids.dual);
}
}
which gives
Integer Model
OBJECTIVE: 3800
Relaxed Model
OBJECTIVE: 3750
dual of the kids constraint = 12.5
The technical post webpages of this site follow the CC BY-SA 4.0 protocol. If you need to reprint, please indicate the site URL or the original address.Any question please contact:yoyou2525@163.com.