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solver:too_many_iterations [2007/07/31 13:14]
127.0.0.1 external edit
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-====== TOO MANY ITERATIONS ====== 
-//Q: I recently ran a small program with two nonlinear constraints,​ but it terminated before it converged at 200 major iterations, even though I set options ''​iterlim = 2000''​. The reason for termination was "''​major iterations terminated before convergence/​ Exit too many iterations''"​. The problem was infeasible when it exited.// 
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-MINOS uses two iteration counts, Minor (or inner iterations) and Major (or outer iterations corresponding to linearizations of the constraints). The Option ''​Iterlim''​ limit is related to Minor Iterations. The limit on Major iterations can only be set in a solver options file; the default limit is 200. 
- 
-You will need a ''​MINOS.OPT''​ file in which you have the line 
-    Major Iterations xxxx 
-and you must tell GAMS to use the file by adding the line 
-   <​modelname>​.optfile = 1; 
-before the SOLVE statement, where ''<​modelname>''​ is the name of your model. ​ 
- 
-If you need more than 200 major iterations for a model with two nonlinear constraints then it is likely that:  
-  * the model is VERY nonlinear or  
-  * you have very bad initial values or  
-  * the model is poorly scaled. ​ 
- 
  
IMPRESSUM / LEGAL NOTICEPRIVACY POLICY solver/too_many_iterations.1185880456.txt.gz ยท Last modified: 2007/07/31 13:14 by 127.0.0.1