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XPRSgetinfeas

XPRSgetinfeas

Purpose
Returns a list of infeasible primal and dual variables.
Synopsis
int XPRS_CC XPRSgetinfeas(XPRSprob prob, int *npv, int *nps, int *nds, int *ndv, int mx[], int mslack[], int mdual[], int mdj[]);
Arguments
prob 
The current problem.
npv 
Pointer to an integer where the number of primal infeasible variables is returned.
nps 
Pointer to an integer where the number of primal infeasible rows is returned.
nds 
Pointer to an integer where the number of dual infeasible rows is returned.
ndv 
Pointer to an integer where the number of dual infeasible variables is returned.
mx 
Integer array of length npv where the primal infeasible variables will be returned. May be NULL if not required.
mslack 
Integer array of length nps where the primal infeasible rows will be returned. May be NULL if not required.
mdual 
Integer array of length nds where the dual infeasible rows will be returned. May be NULL if not required.
mdj 
Integer array of length ndv where the dual infeasible variables will be returned. May be NULL if not required.
Error values
91 
A current problem is not available.
422 
A solution is not available.
Related controls
Double
FEASTOL 
Tolerance on RHS.
OPTIMALITYTOL 
Reduced cost tolerance.

Example
In this example, XPRSgetinfeas is first called with nulled integer arrays to get the number of infeasible entries. Then space is allocated for the arrays and the function is again called to fill them in: 
int npv, nps, nds, ndv, *mx, *mslack, *mdual, *mdj;
...
XPRSgetinfeas(prob, &npv, &nps, &nds, &ndv,
              NULL, NULL, NULL, NULL);
mx = malloc(npv * sizeof(*mx));
mslack = malloc(nps * sizeof(*mslack));
mdual = malloc(nds * sizeof(*mdual));
mdj = malloc(ndv * sizeof(*mdj));
XPRSgetinfeas(prob, &npv, &nps, &nds, &ndv,
              mx, mslack, mdual, mdj);
Further information
1. To find the infeasibilities in a previously saved solution, the solution must first be loaded into memory with the XPRSreadbinsol ( READBINSOL) function.
2. If any of the last four arguments are set to NULL, the corresponding number of infeasibilities is still returned.
Related topics
XPRSgetscaledinfeas, XPRSgetiisdata, XPRSiisall, XPRSiisclear, XPRSiisfirst, XPRSiisisolations, XPRSiisnext, XPRSiisstatus, XPRSiiswrite, IIS.

Parent Topic Console and Library Functions

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