Originally posted by: ga67liv
Hi, I just wrote that code in CPLEX, syntax seems to be alright, but i got some failure reporting.
the code:
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//indices
{string} machine = ...;
{string} period = ...;
//parameters
float demand[period] = ...;
float demandfactor = ...;
float minoutput[machine] = ...;
float maxoutput[machine] = ...;
int maxnumber[machine] = ...;
int hours[period] = ...;
float fixcost[machine] = ...;
float addcost[machine] = ...;
float startcost[machine] = ...;
//decision variables
dvar int+ number[period][machine];
dvar float+ generate[period][machine];
dvar boolean use[period][machine];
//objective function
minimize sum(p in period, m in machine) use[p][m]*number[p][m]*(startcost[m] + fixcost[m]*hours[p] + ((generate[p][m] - (minoutput[m]*hours[p]))*addcost[m]));
//constraints
subject to{
forall(p in period)
sum(m in machine)
hours[p]*number[p][m]*generate[p][m] <= demand[p]*demandfactor;
forall(p in period, m in machine)
generate[p][m] <= maxoutput[m];
forall(p in period, m in machine)
generate[p][m] >= minoutput[m];
forall(p in period, m in machine)
number[p][m] <= maxnumber[m];
}
__________________________________________
the failure reports:
CPLEX(default) cannot extract expression: minimize sum(p in period, m in machine) (use[p][m]*number[p][m])*(startcost[m]+fixcost[m]*hours[p]+(generate[p][m]+(minoutput[m]*hours[p])*(-1))*addcost[m])
and
CPLEX(default) cannot extract model: IloAlgorithm cannot extract extractable.
the failure is displayed on the line ob the objective function. I really hope that one of you can help me,
thanks, Philipp
#DecisionOptimization#MathematicalProgramming-General