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I am trying to load a CPLEX LP file in to CPLEX using the "read" command. I believe that in this problem, I have a set of constraints that are quadratic. But, from what I understand CPLEX will still attempt to solve quadratic programming problems.

However, when I try to read it in, I get this error:

CPLEX Error  1437: Line 284: Illegal quadratic constraint sense.

Is there something special I need to do to read in a quadratic programming problem?

NOTE: I am able to load this LP file in to scip and solve it using: scip -f

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Looks like a programming problem. Is there not a computing website where this question would be more clearly on-topic? – Gerry Myerson Apr 11 '12 at 5:33
I can try stackoverflow, but I figured more math users would be likely to use cplex – gnychis Apr 11 '12 at 14:52
This is pretty much off-topic. – Mariano Suárez-Alvarez Oct 25 '12 at 16:42

CPLEX solves only convex optimization problems. No math programming instance with a nonlinear equality constraint can be convex, so cplex will refuse to attempt to solve any problem with such a constraint.

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