GAMS World Forum

You probably solved the non-convex model with a local solver (CONOPT) that gets stuck. The model is small enough to ask a global solver if the model is truly infeasible or if you need to pay more attention in setting a good starting point for your local solver. It turns out the latter is true. I so...

Dear all, I establish a model recently. The code runs successfully but the solution is infeasible. GAMS shows that there are no superbasic variables. This is a quite simple model but I don't know what the problems is after checking for several time. Could anyone help me? Thanks for your prompt atten...

You can't write constraints like this in GAMS: if((ud11=0)and(ud12=0)and(ud13=0), ud1.fx=1; else ud1.fx=0;); GAMS requires your to rewrite your constraint without if , and and else . While there are systems that automatically rewrite this for you they often do a poor job. Often you can reuse subexp...

Hello all, I am doing optimization for devices' capacity in order to minimum the cost under the circumstance that every node's voltage is maintained in an acceptable level. The mathematical expression of the model ,the code and the log are attached. Error 141 and 143 are alarmed repeatedly. So,pleas...