package com.imsl.test.example.math;

import com.imsl.io.*;
import com.imsl.math.*;
import java.io.*;
import java.text.*;

/**
 * <p>
 * SparseLP Example 2: Solves a linear programming problem defined in an MPS
 * file.</p>
 *
 * <p>
 * This example demonstrates how the class <code>MPSReader</code> can be used
 * with <code>SparseLP</code> to solve a linear programming problem defined in
 * an MPS file. The MPS file used in this example is an uncompressed version of
 * the file 'afiro', available from
 * <a class="pdf" href="http://www.netlib.org/lp/data/">http://www.netlib.org/lp/data/</a>.
 * </p>
 *
 * @see <a href="SparseLPEx2.java">Code</a>
 * @see <a href="doc-files/SparseLPEx2.out">Output</a>
 */
public class SparseLPEx2 {

    public static void main(String args[]) throws Exception {
        //Read the problem from the file.
        try (InputStream stream = SparseLPEx2.class.getResourceAsStream("afiro");
                Reader reader = new InputStreamReader(stream)) {
            MPSReader mps = new MPSReader();
            mps.read(reader);

            // Solve problem.
            SparseLP lp = new SparseLP(mps);
            lp.setPresolve(6);
            lp.solve();

            // Print solution.
            System.out.println("Problem Name: " + mps.getName());
            System.out.printf("Objective:  %.2f\n", lp.getOptimalValue());

            NumberFormat nf = NumberFormat.getInstance();
            nf.setMaximumFractionDigits(1);
            nf.setMinimumFractionDigits(1);

            PrintMatrixFormat mf = new PrintMatrixFormat();
            mf.setNumberFormat(nf);
            mf.setNoColumnLabels();

            new PrintMatrix("Solution:").print(mf, lp.getSolution());
            // Close all resources.
        }
    }
}