package com.imsl.test.example;

import com.imsl.*;
import com.imsl.stat.*;
import java.io.*;

/**
 * Captures a warning message and reprints the message later.
 *
 * This example shows how to issue warning messages instead of using the
 * default <code>System.err</code>. 
 *
 *
 * @see <a href="WarningEx1.java">Code</a>
 * @see <a href="doc-files/WarningEx1.out">Output</a>
 *
 */
public class WarningEx1 {

    public static void main(String args[]) throws Exception {
        // Capture warning message.
        WarningObject w = Warning.getWarning();

        ByteArrayOutputStream os = new ByteArrayOutputStream();
        PrintStream ps = new PrintStream(os);

        WarningObject newWarning = new WarningObject();
        newWarning.setOut(ps);
        Warning.setWarning(newWarning);

        // Seed the random number generator
        Random rn = new Random();
        rn.setSeed(123457);
        rn.setMultiplier(16807);

        // Construct a ChiSquaredTest object
        CdfFunction bindf = new CdfFunction() {
            public double cdf(double x) {
                return Cdf.binomial((int) x, 5, 0.3);
            }
        };

        double cutp[] = {0.5, 1.5, 2.5, 3.5, 4.5};
        int nParameters = 0;
        ChiSquaredTest cst = new ChiSquaredTest(bindf, cutp, nParameters);
        for (int i = 0; i < 1000; i++) {
            cst.update(rn.nextBinomial(5, 0.3), 1.0);
        }

        // Print goodness-of-fit test statistics
        System.out.println("The Chi-squared statistic is "
                + cst.getChiSquared());
        System.out.println("The P-value is " + cst.getP());
        System.out.println("The Degrees of freedom are "
                + cst.getDegreesOfFreedom());

        // Print warning message.
        System.out.println(os.toString());

        // Restore Warning.
        Warning.setWarning(w);
        ps.close();
        os.close();
    }
}