Originally posted by: 1259

Hi,

I am so sorry for disturbing

I am new in cplex. I have a problem, could anybody please help me??

I deal with a RCPSP model. I have an error that I cannot pass over . The error says the operator not available for..

Actually I have a decision variable S[i] that defines start time of activity i. For each activity there is a precedency relationship. That is to say, for starting activity j there is a need to complete the predecessor activity i. so the start time of activity j is:  S[i] >=S[i] +duration[i] 

I define the parameters of the activities and S[i]  as follows:

tuple Task{

key int ID;

int duration;

int EarliestStart;

int LatestStart;

int Latestfinish;

int duedate;

int demand resource;

{int} pred;}

 

//variables

dvar int+ S[i]; 

 

then in the constraints I define:

forall (i in Tasks, j in i.pred)

S[i] >=S[i] +i.duration;

At this constraint I have the above mentioned error. Could you please help me how can I solve this error?

Best regards

 

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#DecisionOptimization
#OPLusingCPLEXOptimizer

Hi,

have you had a look at the example

#DecisionOptimization
#OPLusingCPLEXOptimizer

Originally posted by: 1259

Hi 

thank you so much for your response. Yes, I have seen. But my problem is a little different.

Actually I solved the error..

 

Best regards 

#DecisionOptimization
#OPLusingCPLEXOptimizer