Gams options

Problems with syntax of GAMS
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Gams options

Post by Ildar » 3 weeks ago

How to understand if options are included in the log file does not write anything
Suppose I want to add these options.
They are in cplex.opt
just can not put a file of this extension

Connect them Shops.OptFile = 1;
In the log you can see that Gams
but did they turn on?

Sorry for my english
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Re: Gams options

Post by dirkse » 3 weeks ago


The log file you sent shows that the option file was read.

You are using a fairly old version of GAMS/CPLEX from 2009. This version doesn't echo the non-default CPLEX options to the log, which would show you that the CPLEX library has accepted the options you have set. But the more recent versions of GAMS do this:

Code: Select all

IBM ILOG CPLEX   26.1.0 rf2b37b9 Released Feb 02, 2019 LEG x86 64bit/Linux    
--- GAMS/Cplex licensed for continuous and discrete problems.

Reading parameter(s) from "/home/sdirkse/support/cplex.opt"
>>  bttol 0.5
Finished reading from "/home/sdirkse/support/cplex.opt"
Reading data...
Starting Cplex...
Space for names approximately 0.28 Mb
Use option 'names no' to turn use of names off
CPXPARAM_Advance                                 0
CPXPARAM_Simplex_Limits_Iterations               2000000000
CPXPARAM_TimeLimit                               1000
CPXPARAM_WorkDir                                 "/home/sdirkse/support/225b/"
CPXPARAM_Threads                                 1
CPXPARAM_Parallel                                1
CPXPARAM_Tune_TimeLimit                          200
CPXPARAM_MIP_Strategy_Backtrack                  0.5
CPXPARAM_MIP_Tolerances_AbsMIPGap                0
CPXPARAM_MIP_Tolerances_MIPGap                   0.050000000000000003
CPXPARAM_MIP_Display                             4
Found incumbent of value 6009.910000 after 0.00 sec. (0.33 ticks)
Tried aggregator 1 time.
If you update your GAMS license, you can update to the most recent version of GAMS/CPLEX and enjoy this and many other new features and capabilities of GAMS/CPLEX and GAMS in general. Also, on the subject of updating, I notice you are using an old license issued to Gary Goldstein at Decision Ware, Inc. If you are still working with Gary, you should arrange with him for an updated license. If you are not, you should contact our sales team to ask about getting your own license.


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