Excel Solver: Constraint Specification

I am having trouble specifying a solver constraint such that:

cell(x) >= cell(y) -or-
cell(x) = 0

How do I implement this? If Excel Solver is not robust enough to implement this condition, would something like Matlab using the optimization toolbox be more appropriate?

Originally Posted by martindwilson

wouldn't that mean if set in constraints that
cell x must be =0
AND
>= cell y
not OR?

If cell(x) must be zero, then the fact that it must be greater than cell(y) is irrelevant.

Cell(x) may only accept values of 0 or any value >= Cell(y) hence the "or".

In mathematical terms, [0] -or- [cell(y), infinity) where cell(y) > 0.

Originally Posted by shg

I'm unsure of your question; you can set either of those constraints directly in the Solver dialog.

OK, how?

If Cell(x) can only take on values of 0 or values greater than Cell(y) and Cell(y) is a positive number, how can this be programmed? I can input the conditions separately, sure, but having two conditions specifying

Cell(x) = 0 and another saying
Cell(x) >= Cell(y)

simply means Cell(x) will always be constrained to 0 (when Cell(y) is negative or 0) or will be in conflict with the second expression.

What I need is: Cell(x) can only take on values of zero, or any real number in the interval [Cell(y), infinity) where Cell(y) > 0.

I should add that Cell(x) is the "changing" cell.