Option specifications

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Each option specification line can contain only one option.  The format for specifying options is as follows,

 

optionkeyword1 modifier or value

optionkeyword2 modifier or value

optionkeyword3 modifier or value

...

Notes:

•The option keyword may consist of one or more words and is not case sensitive.
•Modifiers are generally text strings but are not always required
•Numerical values are not always required and when entered may be either an integer or a real constant.  Real numbers may be expressed in F, E, or D formats.
•Any errors in the spelling of the keyword(s) or modifiers will lead that option to not be understood and therefore disregarded by the solver.

Examples:

Consider the following CPLEX options file,

 

* CPLEX options file

barrier

IIS yes

preind 0

 

The first line begins with an asterisk and therefore contains comments.  The barrier entry specifies the use of the barrier algorithm to solver the linear programming problem, while the IIS indicates the irreducible infeasible set option is to be used on infeasible models and preind turns off the presolve.  Details on these options can be found in the CPLEX solver manual.

 

Also consider the following MINOS options file,

 

Major iterations 2000

Scale all variables

feasibility tolerance 1.0e-5

 

The first option sets the major iteration limit to 2000.  The second line tells MINOS to scale all variables including the ones with nonlinear terms.  The third option sets the feasibility tolerance.  Details on these options can be found in the MINOS solver manual.