Paul,

Shouldn’t your “or” operator be “and” (&&)? Don’t you want p2, p4, and p5 to all be less than p1? Or am I misreading your description?

Regards,

Neil

Paul,

Yes, the &&'s are not needed.

As a side note, if you use && or || I like to use parenthesis -- && and || have a high precedence so you can get some strange results if the input can be interpreted two ways. So my practice is to always type (p1>p2)&&(p1>p4) In this case it is not needed but I've been burned by the case when the && operates on the two expression halves first.

Regards,

Neil

If there are 19 variables, then why are there only 11 in your code and what does "..." mean?

I think I see part of the problem. Looking closely at your list of constraints there, you see instances like “p1 >= p2” and later “p2 >= p1”. That implies that “p1 == p2”, so a solution will only be found if that is true. There are a number of instances in your constraint set where equality is implied, even though you specified the constraints as >= inequalities. I am guessing that a result of this is that your constraint that all of the variables add to 58 is unsatisfiable, so the solver returns nothing. If I have time after I grab lunch, I might see if it becomes clearer if the system of equations is simplified by hand (e.g., manually replace pairs of constraints like p1 >= p2, p2 >= p1 with one constraint that p1 == p2.)