/***************************************************************************************\
* Name:        MipSolPool.java                                   Fair Isaac 13/06/2008 *
* Purpose:     All solutions with the MIP solution pool                                *
* Description: We take the power generation problem stored in hpw15.mps which seeks to *
*              optimise the operating pattern of a group of electricity generators. We *
*              solve the problem collecting all solutions found during the MIP search. *
*              The optimal solution's objective and solution values are printed to     *
*              screen.                                                                 *
* Input:       hpw15.mps                                                               *
\***************************************************************************************/

import java.io.*;
import com.dashoptimization.*;

public class MipSolPool {
    public static void main(String[] args) throws Exception {
        String model = args.length == 0 ? "../data/hpw15" : args[0];
        try (XPRSprob prob = new XPRSprob(null);
             XPRSmipsolpool msp = new XPRSmipsolpool())
        {
            prob.addMsgHandlerListener(System.out);

            msp.probAttach(prob);

            prob.readProb(model);

            prob.optimize();

            int nSols = msp.attributes().getSolutions();

            if (nSols>0) {
                IntHolder iSolutionId = new IntHolder();
                DoubleHolder dObj = new DoubleHolder();
                msp.getDblAttribProbExtreme(prob,0,iSolutionId, XPRS.MSP_SOLPRB_OBJ, dObj);

                System.out.println("Optimal Solution ID: " + iSolutionId.value);
                System.out.println("Optimal Objective  : " + dObj.value);


                int nCols = msp.getIntAttribSol(iSolutionId.value, null, XPRS.MSP_SOL_COLS);
                for (int i=0;i<nCols;i++) {
                    double[] dSol = new double[1];
                    msp.getSol(iSolutionId.value,null,dSol,i,i,null);
                    System.out.println(i + " = " + dSol[0]);
                }
            }

            msp.probDetach(prob);
        }
    }
}