ILOG CPLEX 11.0 User's Manual

Fixing Parameters and Tuning Multiple Models in the Interactive OptimizerThe command to invoke the tuning tool in the Interactive Optimizer is: tuneOptionally, that command may take one or two arguments, in either order, like this:tune paramfile.prm modelfileortune modelfile paramfile.prmThe following sections explain those optional arguments.◆ Fixed Parameters to Respect on page 165◆ Files of Models to Tune on page 165Fixed Parameters to RespectIf you supply an optional file name with the extension.prm, that file contains the formattedlist of parameters and their values that you do not want ILOG CPLEX to tune. That is, youwant ILOG CPLEX to respect those parameter settings. If you do not supply a parameter fileto the tune command, then all parameters are subject to tuning.For example, if you have a model that you know has numerical issues, and you have alreadydetermined that you want to set the numerical emphasis parameter yourself, then a PRM filesuitable for tuning your model would contain the following heading and parameter setting:CPLEX Parameter File Version 11.0.0CPX_PARAM_NUMERICALEMPHASIS 1An easy way to generate a PRM file with a correct heading and fixed parameter settings is toread your model, set the parameters you wish, and write a PRM file from the InteractiveOptimizer, with this command:write filename.prmFiles of Models to TuneIf you supply an optional file name, such as modelfile, that file contains a list of files, onefile name per line. Each file contains a model to tune. Each file must specify its type, such as.mps, .lp, or .sav, as the extension in the file name. Optionally, those cited files may becompressed, as specified by the extension .gz or .bz2. Here is an example of the contents ofsuch a file, specifying three compressed files of type .mps available in the current workingdirectory:p0033.mps.gzp0548.mps.gzp2756.mps.gzILOG CPLEX 11.0 — USER’ S MANUAL 165