Originally posted by: BCDS_Daniel_Underwood

I'm using OPL in Linux. I create OPL source code files, then run them using oplrun. How can I disable cuts in my source code file? (All cuts, MIR cuts, flow cuts, Gomory cuts, etc...)
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Originally posted by: BCDS_Daniel_Underwood

I see the parameter options that I need to set, for example

http://publib.boulder.ibm.com/infocenter/cosinfoc/v12r3/index.jsp?topic=%2Filog.odms.cplex.help%2FContent%2FOptimization%2FDocumentation%2FOptimization_Studio%2F_pubskel%2Fps_refparameterscplex2366.html

is one of them. But in general, I don't know how to set such options in a source code file.

So does anyone know how to set such parameters in an OPL source code file?
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Originally posted by: BCDS_Daniel_Underwood

I have read that I can set CPLEX parameters by adding code such as

execute PARAMS {
  cplex.tilim = 100;
}

to my source code file. So does this code need to go anywhere in particular in my source code file? (For example, does it need to appear before my math program (model) definition? Or will it work anywhere in the source code?
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#OPLusingCPLEXOptimizer

Originally posted by: SystemAdmin

> So does this code need to go anywhere in particular in my source code
> file? (For example, does it need to appear before my math program
> (model) definition? Or will it work anywhere in the source code?

You are correct in using such execute blocks. Given that you need
to apply these CPLEX settings before the model runs, they should be
present anywhere before the maximize and subject to blocks in the .mod
file and are called pre-processing blocks.

More on these pre/post-processing blocks can be found in the following doc link:

http://publib.boulder.ibm.com/infocenter/cosinfoc/v12r3/index.jsp?topic=%2Filog.odms.ide.help%2FContent%2FOptimization%2FDocumentation%2FOptimization_Studio%2F_pubskel%2Fps_opl_Language668.html

> How can I disable cuts in my source code file? (All cuts, MIR cuts,
> flow cuts, Gomory cuts, etc...)

The simplest way to disable all the cuts that CPLEX would add by default,
would be to set the CutsFactor parameter to 1 or less. More about the parameters
that control cuts can be found in the following doc link:

http://publib.boulder.ibm.com/infocenter/cosinfoc/v12r3/index.jsp?topic=%2Filog.odms.cplex.help%2FContent%2FOptimization%2FDocumentation%2FOptimization_Studio%2F_pubskel%2Fps_usrmancplex1842.html
One such .mod file could look like the following:

range r = 1..5; 

int y[i in r] = i; execute
{ cplex.cutsfactor=0; 
} dvar int+ x[r]; minimize sum(i in r) x[i]; subject to 
{ forall(i in r) x[i] >= y[i]; 
}

Hope this helps.
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#OPLusingCPLEXOptimizer

Originally posted by: BCDS_Daniel_Underwood

Perfect! Thanks a lot :)
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