Originally posted by: M.Heshmat

Hello there,

I have an error called {Cannot use the type int with "in"}. Could you help me to remove this error, please? 

I am attaching the .mod file.

Thank you.

Hi,

after "in" you should have a set or a range, not a number.

So for example, you should change

Constraint10: sum(j in Nurses,k in Chairs, s in (S-R[i]+1)) y[i,j,k,s]==1;

into

Constraint10: sum(j in Nurses,k in Chairs, s in (S-R[i]+1..S-R[i]+1)) y[i,j,k,s]==1;
    

to get rid of the error

regards

Originally posted by: M.Heshmat

Dear Alex,

Thank you very much.

Best Regards

Originally posted by: M.Heshmat

Dear Alex,

I have changed the number into range, and the error has been gotten rid. However, Cplex cannot extract the model. Maybe a logical error.

Could you give me a piece of advice? 

Thanks

The error I get for your model is "Variables are not supported in ranges when not fixed". And I think that pretty clearly tells what is wrong: You are using a decision variable as the bound of a range. That is not supported. I think the problematic parts of your model are the ones in red below

Constraint11: sum(i in Patients, j in Nurses, t in (v..u)) y[i,j,k,t]<=1;
constraint12: sum(i in Patients, k in Chairs,t in (w..x))

where the range of t is bounded by decision variables.

However, the quantities v, u, w, x do not need to be decision variables. You can define them as

 int v[i in Patients][s in Slots] = maxl(s-R[i]+1,1);
 int u[i in Patients][s in Slots] = minl((S-R[i]+1),s);
 int w[i in Patients][s in Slots] = maxl(s-R[i]+1,1);
 int x[i in Patients][s in Slots] = minl((S-R[i]+1),s);

and then write the constraints as

Constraint11: sum(i in Patients, j in Nurses, t in (v[i][s]..u[i][s])) y[i,j,k,t]<=1;
constraint12: sum(i in Patients, k in Chairs,t in (w[i][s]..x[i][s])) A[i]*y[i,j,k,t]<=Amax;

Originally posted by: M.Heshmat

Thank you very much, I really appreciate that.