The routine CPXiiswrite is used to write an LP format file containing the rows and columns in the Irreducibly Inconsistent Set (IIS) of an infeasible LP. Note that the infeasibility must previously have been detected by a simplex optimizer. If an IIS has already been obtained using the same method as is currently specified by the IIS algorithm indicator CPXPARAM_IISIND, CPXiiswrite simply writes an LP format file containing the existing IIS. If no IIS has been computed, or the IIS algorithm differs from the one used to compute the available IIS, CPXiiswrite first computes an IIS, then writes its LP format representation out.

Example

 status = CPXiiswrite (env, lp, "myprob.iis");