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XPRSiisnext

XPRSiisnext


Purpose
Continues the search for further Irreducible Infeasible Sets (IIS), or calls XPRSiisfirst ( IIS) if no IIS has been identified yet.
Synopsis
int XPRS_CC XPRSiisnext(XPRSprob prob, int *status_code);
Arguments
prob 
The current problem.
status_code 
The status after the search:
success;
no more IIS could be found, or problem is feasible if no XPRSiisfirst call preceded;
on error (when the function returns nonzero).
Example
This looks for a further IIS.
XPRSiisnext(prob,&status_code);
Further information
1. Calling IIS -n from the console has the same effect as this function.
2. A model may have several infeasibilities. Repairing a single IIS may not make the model feasible. For this reason the Optimizer attempts to find an IIS for each of the infeasibilities in a model. You may call the XPRSiisnext function repeatedly, or use the XPRSiisall ( IIS -a) function to retrieve all IIS at once.
3. This function is not affected by the control MAXIIS.
4. If the problem has been modified since the last call to XPRSiisfirst or XPRSiisnext, the generation process has to be started from scratch.
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