Hello,

I’ve been using JuMP for my computations and its one of the best experiences I’ve had with a mathematical programming language. I recently ran into a problem solving one of my models. It turns out that the solution I get is infeasible. While trying to identify the problem in my model, I also bothered to check the LP file where I found some constraints of this form:

c146: <= 0

c147: <= 0

c148: <= 0

c149: <= 0

c150: <= 0

c151: <= 0

c152: <= 0

c153: <= 0

c154: <= 0

c155: <= 0

c156: <= 0

c157: <= 0.5

c158: <= 0.5

c159: <= 0.5

c160: <= 0.5

Could these also be one of the reasons why the solution is wrong? In the original constraint, I equate a variable to a certain value provided the indices of the variable belong to a certain domain. The constraint I modelled in JuMP looks like this: x[t,v,n]*(n in v.list) <= 0.5*(v!=1).

Thanks in advance

# Is not having the LHS in some constraints in the LP problematic?

**varun7rs**#1

**joehuchette**#2

If you are getting a solution that you believe is invalid, you are most likely modeling your problem incorrectly. You’ll have to look over the logic of your model to understand why this is. On it’s face, there is nothing “wrong” with the constraints you’ve shared.

**varun7rs**#3

Thank you. I’ve identified the infeasibility in the constraints model and now it works as usual.