Originally posted by: Hosssein

Hi,

In my CP model, W is the set of variables.

could you please tell me how I can create the following expression?

(W[1]==1) && (W[2]==1) .... && (W[n]==1)

Note that I dont know the value of n beforehand, So I need to create it in a loop like below:

for (int i=1; i<=n ; i++){

     Expression := Expression && (W[i]==1)

}
I could not do this by IloNumExpr. Could you please tell me what I have to do ?

Thanks in advance for your help.

Originally posted by: rdumeur

Dear Hussein,

the && operator is only defined on constraints. If you want to use it within an expression you need to do something like:

#include <ilcp/cp.h>

IloInt someValue(IloInt x);

int main() {
  IloEnv        env;
  IloModel        model(env);
  IloInt        n(10);
  IloIntVarArray    vars(env, n, 0, 10);
  IloConstraint       c;
  for(IloInt i(0); i < 10; ++i) {
    IloConstraint    test(vars[i] == someValue(i));
    if(i  == 0)
      e = test;
    else
      e = e && test; // compose constraints with &&
  }
  // do whatever you want with e

  // to use constraint e as an expression you can  do (e == <boolean value>).

}
 

I hope this helps.

Cheers,

   Renaud

Originally posted by: Hosssein

Thank you so much ;))))