/***************************************************************************************\ * Name: MipSolEnum.java Fair Isaac 13/06/2008 * * Purpose: 10 best solutions with the MIP solution enumerator * * Description: We take the power generation problem stored in hpw15.mat which seeks to * * optimise the operating pattern of a group of electricity generators. We * * run the MIP solution enumerator on the problem using the default setup * * obtaining the best 10 solutions. The best 10 solutions are stored to a * * MIP solution pool. The solutions' objectives and solution values are * * printed to screen. * * Input: hpw15.mat * \***************************************************************************************/ import java.io.*; import com.dashoptimization.*; public class MipSolEnum { public static void main(String[] args) throws Exception { XPRS.init(); try { XPRSprob prob = new XPRSprob(); prob.addMsgHandlerListener(System.out); XPRSmipsolpool msp = new XPRSmipsolpool(); XPRSmipsolenum mse = new XPRSmipsolenum(); prob.readProb("../data/hpw15"); int nCols = prob.attributes().getCols(); /* Avoid duplicated solutions from heuristics. */ msp.controls().setDuplicateSolutionsPolicy(3); /* Disable dual reductions to prevent dominated solutions from being */ /* presolved away. */ prob.controls().setMIPDualReductions(2); /* Run the enumeration */ IntHolder nMaxSols = new IntHolder(10); mse.minim(prob,msp,new XPRSdefaultMipSolEnumHandler(), null, nMaxSols); /* Print out the solutions found */ int nSols = mse.attributes().getSolutions(); for (int i=1;i<=nSols;i++) { int[] iSolutionId = new int[1]; DoubleHolder dObj = new DoubleHolder(); mse.getSolList(XPRS.MSE_METRIC_MIPOBJECT,i,i,iSolutionId,null,null); mse.getSolMetric(iSolutionId[0], null, XPRS.MSE_METRIC_MIPOBJECT, dObj); System.out.println("--------\n" + i + " = " + dObj.value); for (int j=0;j<nCols;j++) {
					double[] dSol = new double[1];
					msp.getSol(iSolutionId[0],null,dSol,j,j,null);
					System.out.println(j + " = " + dSol[0]);
				}
			}

		} finally {
			XPRS.free();
		}
	}
}