Hello everybody,

I have a little question regarding an optimization problem. In the problem I define my binary variables by use of two sets (matrix). Rows: Set 1, Columns: Set 2.

The first set contains different parts (Set1 contains: Part 1, Part 2, Part 3… and so on)

The second set contains different variants for each part (Set 2 contains: Version 1, Version 2, Version 3 and so on).

The definition of the indices is no problem. Later in the model I want to use not the whole Matrix (Set1 X Set2) but just a Single vector. For example the vector should have the size of Set 1, and of Set 2 just the colum Version 2. So in the constraint I just want to use the yellow colum. Is this possible or do I have to define for every Element of Set 2 an own Set?

**Best answer by Marcel Hunting**