presolve dual setting
Decides whether CPLEX presolve should pass the primal or dual linear programming problem to the linear programming optimization algorithm.
Purpose
Presolve dual setting
API | Parameter Name | Name prior to V12.6.0 |
---|---|---|
C | CPXPARAM_Preprocessing_Dual | CPX_PARAM_PREDUAL |
C++ | IloCplex::Param::Preprocessing::Dual | PreDual (int) |
OPL | predual | |
Interactive | preprocessing dual | preprocessing dual |
Identifier | 1044 | 1044 |
Description
Decides whether CPLEX presolve should pass the primal or dual linear programming problem to the linear programming optimization algorithm. By default, CPLEX chooses automatically.
If this parameter is set to 1 (one), the CPLEX presolve algorithm is applied to the primal problem, but the resulting dual linear program is passed to the optimizer. This is a useful technique for problems with more constraints than variables.
When this parameter is set to 0 (zero, its default value) or 1 (one, turned on), CPLEX disables crushing and uncrushing of the model by such routines as CPXuncrushx. To use CPXuncrushx effectively, you must set the value of this parameter to -1, turning off this feature.
Value | Meaning |
---|---|
-1 | Turn off this feature |
0 | Automatic: let CPLEX choose; default |
1 | Turn on this feature |