Dear All,
I run model in Gams and received following result
constraint(S1,S6)… - F(S1,S5) + F(S1,S6) =G= 0 ;
(LHS = -47500, INFES = 47500 ***)
Is there a problem? What can I do?
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Hi ?
No there is not a problem: Gams writes your model equations in a linearized form for your information. It puts in the start values and evaluates the expression. In this case, you see that the variables on the left hand side add to -47500 and the right hand side is 0 (Gams puts all the variables on the left side). This is a great tool for cheching your model. If you calibrated your model properly and added the benchmark values, you would have no infeasibility if the model is correct.
For example, you have an equation
X + Y +2 =E= 0
in your model, and you run your model with as starting values X.L = 3 and Y.L = -1, you will have no infeasibility. If you run your model without these starting values, you will get the information that there is an infeasibility at the start point of 2.
Gams would still solve the model (and if the model is correct) give you the values of 3 and -1.
Hope this helps
Renger
On Fri, Sep 7, 2012 at 9:54 PM, esra wrote:
Dear All,
I run model in Gams and received following result
constraint(S1,S6)… - F(S1,S5) + F(S1,S6) =G= 0 ;
(LHS = -47500, INFES = 47500 ***)
Is there a problem? What can I do?
Renger van Nieuwkoop
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Dear Esra
This is based on your initial values. You can provide a feasible initial guess, that is very important for NLP models.
I hope that helps.
Regards
On Sat, Sep 8, 2012 at 3:54 AM, esra wrote:
Dear All,
I run model in Gams and received following result
constraint(S1,S6)… - F(S1,S5) + F(S1,S6) =G= 0 ;
(LHS = -47500, INFES = 47500 ***)
Is there a problem? What can I do?
To post to this group, send email to gamsworld@googlegroups.com.
To unsubscribe from this group, send email to gamsworld+unsubscribe@googlegroups.com.
For more options, visit this group at http://groups.google.com/group/gamsworld?hl=en.