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XPRSgetiis

Purpose
Retrieves the final Irreducible Infeasible Set (IIS) found in an IIS search.
Synopsis
int XPRS_CC XPRSgetiis(XPRSprob prob, int *colnumber, int *rownumber, int miiscol[], int miisrow[]);
Arguments
prob 
The current problem.
colnumber 
Number of columns in the IIS.
rownumber 
Number of rows in the IIS.
miiscol 
Integer array of length colnumber containing the column indices for the IIS set. May be NULL if not required.
miisrow 
Integer array of length rownumber containing the row indices for the IIS set. May be NULL if not required.
Related Controls
Integer
Number of Irreducible Infeasible Sets to be found

Example
The following finds and retrieves an IIS in the problem prob :
int ncols, nrows, *miiscol, *miisrow;
...
XPRSiis(prob,"");
XPRSgetiis(prob,&ncols,&nrows,NULL,NULL);
miiscol = malloc(ncols*sizeof(int));
miisrow = malloc(nrows*sizeof(int));
XPRSgetiis(prob,&ncols,&nrows,miiscol,miisrow);
Further information
1. XPRSgetiis can only be called after the function XPRSiis, which computes the IISs in a problem.
2. To retrieve all of the IIS in a problem, you need to call XPRSiis and XPRSgetiis repeatedly, setting MAXIIS to 1, then 2, then 3, etc. For example: 
XPRSiis(prob, "");
XPRSgetintattrib(prob, XPRS_NUMIIS, &niis);
for (i=1; i<=niis; i++) {
  XPRSsetintcontrol(prob, XPRS_MAXIIS, i);
  XPRSiis(prob, "");
  XPRSgetiis(prob, &ncols, &nrows, miiscol, miisrow);
  /* display or use IIS */
}

Related topics
XPRSiis.

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