division zero problem

GAMS
1

Dear All,
I build a MINLP model using GAMS.
One of equation is as follows:
eq_v(K,L)… v(K,L)=e=dL(L)/(d(K,L)-a(K,L));
v, d, a are variables, K ,L are sets, dL(L) is a parameter.
The model has no syntax errors, but when I run it, it reports that this equation has division zero errors and exits.
How can I tackle this problem?
Hu

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2

Hu
During the search the solver may set values to a(K,L) which leads the denominator (d(K,L)-a(K,L)) = 0. You can multiply both sides of the equality by the denominator, resulting:
eq_v(K,L)… v(K,L)*(d(K,L)-a(K,L))=e=dL(L);

You you have only a variable in the denominator you can set the variable lower bound to avoid zero division:
a.lo(K,L) = 0.00001;


Regards

2011/8/17 胡辉

Dear All,
I build a MINLP model using GAMS.
One of equation is as follows:
eq_v(K,L)… v(K,L)=e=dL(L)/(d(K,L)-a(K,L));
v, d, a are variables, K ,L are sets, dL(L) is a parameter.
The model has no syntax errors, but when I run it, it reports that this equation has division zero errors and exits.
How can I tackle this problem?
Hu

\

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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.



\

Edson Valle
edsoncv@gmail.com

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