Originally posted by: fizazul

Dear all,

I have a model constructed with OPL language using cp.
here i attach the model and the data.
my problem is after finish running the program,
the decision variable give 'no value' eventhough my formulation is right.
so, i don't know what is the problem with my program.
can someone check for me where the problem is.

Thank advance,

using CP;   

float sigma=...; 

float alpha=...; 

int hd=...; 

int hb=...; 

int S=...; 

int Ab=...; 

float beta=...; 

int Av=...; 

int hv=...; 

int P=...;   
//decision variables dvar 

int nv; dvar 

int nb; dvar 

int q2 in 1000..500000; dexpr 

float q1=q2/1000; dvar 

int T2 in -1000000..1000000; dexpr 

float T=T2/1000; 
//objective function maximize (-(((-1+beta)*(hd*q1))/(-2+beta))-((1/2)*(-1+nb)*(hb*q1 ))-((Ab/nb+S)/T ) +(1/2*nb*(1-nv )*(q1*hv))-((nb*((((q1 )^2)*hv)/T))/P+nb*nv*((((q1)^2)*hv)/(2*P*T))) -(Av/(nb*nv*T))+((q1*sigma)/T));   subject to 
{ ct1: T==(((q1)^(1-beta))/(alpha *(1-beta))); ct2: q2 >=1000; ct3: q2 <=500000; 
}

sigma=30; alpha=100; hd=20; hb=5; S=25; Ab=100; beta=0.01; Av=400; hv=4; P=4500;

#DecisionOptimization
#OPLusingCPLEXOptimizer

Hi,

I see

/T

in your objective and wonder whether this is normal since T could be 0.

If you remove your objective and turn your constraints into

subject to { 
   
   ct1:abs(T-(((q1)^(1-beta))/(alpha *(1-beta))))<=1e-8;
   ct2: q2 >=1000;
   ct3: q2 <=500000;
  }

then you get a solution

Regards
#DecisionOptimization
#OPLusingCPLEXOptimizer