Originally posted by: Max518

Hi,

i have two decision variables and i want to programme the expression:

X*Y∈{0,1}

in the constraints.

can anyone provides a example?

Hi,

are  X and Y integer decision variables ?

regards

Originally posted by: Max518

Hi,

 yes, they are. i defined them as:

//decision variables
dvar int Transport[f in Trucks][i in Jobs] in 0..1;
dvar int JobSequence[f in Trucks][i in Jobs][j in NullJobs] in 0..1;

Hi

then you could write xy==1 as

dvar int x in -1..1;
dvar int y in -1..1;

subject to
{
(x==0) || (y==0) || (x==1) && (y==1) || (x==-1) && (y==-1);
}

but for sure if x and y are binary xy will be either 0 or 1

regards

Originally posted by: Max518

Hi,

i have another problem. my model is about job assignment. however, only six jobs of ten jobs can be assigned. 

i cannot find the problem. could you help me?

attached is my code.

thank you so much.