set_improve

Specifies the iterative improvement level.

void set_improve(lprec *lp, int improve);

Return Value

set_improve has no return value.

Parameters

Pointer to previously created lp model. See return value of make_lp, copy_lp, read_lp, read_LP, read_mps, read_freemps, read_MPS, read_freeMPS, read_XLI

improve

Specifies the iterative improvement level. Can by any of the following values:

IMPROVE_NONE (0) improve none

IMPROVE_SOLUTION (1) Running accuracy measurement of solved equations based on Bx=r (primal simplex), remedy is refactorization.

IMPROVE_DUALFEAS (2) Improve initial dual feasibility by bound flips (highly recommended, and default)

IMPROVE_THETAGAP (4) Low-cost accuracy monitoring in the dual, remedy is refactorization

IMPROVE_BBSIMPLEX (8) By default there is a check for primal/dual feasibility at optimum only for the relaxed problem, this also activates the test at the node level

Remarks

The default is IMPROVE_DUALFEAS + IMPROVE_THETAGAP (6).

Example

#include <stdio.h>
#include <stdlib.h>
#include "lp_lib.h"
int main(void)
{
 lprec *lp;
 /* Create a new LP model */
 lp = make_lp(0, 0);
 if(lp == NULL) {
 fprintf(stderr, "Unable to create new LP model\n");
 return(1);
 }
 set_improve(lp, IMPROVE_DUALFEAS | IMPROVE_BBSIMPLEX);
 delete_lp(lp);
 return(0);
}

lp_solve API reference