MaxTest.java :  » Science » Apache-commons-math-2.0 » org » apache » commons » math » stat » descriptive » rank » Java Open Source

/*
 * Licensed to the Apache Software Foundation (ASF) under one or more
 * contributor license agreements.  See the NOTICE file distributed with
 * this work for additional information regarding copyright ownership.
 * The ASF licenses this file to You under the Apache License, Version 2.0
 * (the "License"); you may not use this file except in compliance with
 * the License.  You may obtain a copy of the License at
 * 
 *      http://www.apache.org/licenses/LICENSE-2.0
 * 
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */
package org.apache.commons.math.stat.descriptive.rank;

import junit.framework.Test;
import junit.framework.TestSuite;

import org.apache.commons.math.stat.descriptive.StorelessUnivariateStatisticAbstractTest;
import org.apache.commons.math.stat.descriptive.UnivariateStatistic;

/**
 * Test cases for the {@link UnivariateStatistic} class.
 * @version $Revision: 762087 $ $Date: 2009-04-05 10:20:18 -0400 (Sun, 05 Apr 2009) $
 */
public class MaxTest extends StorelessUnivariateStatisticAbstractTest{

    protected Max stat;
    
    /**
     * @param name
     */
    public MaxTest(String name) {
        super(name);
    }

    public static Test suite() {
        TestSuite suite = new TestSuite(MaxTest.class);
        suite.setName("Max  Tests");
        return suite;
    }
    
    /**
     * {@inheritDoc}
     */
    @Override
    public UnivariateStatistic getUnivariateStatistic() {
        return new Max();
    }

    /**
     * {@inheritDoc}
     */
    @Override
    public double expectedValue() {
        return this.max;
    }
    
    public void testSpecialValues() {
        double[] testArray = {0d, Double.NaN, Double.NEGATIVE_INFINITY, 
                Double.POSITIVE_INFINITY};
        Max max = new Max();
        assertTrue(Double.isNaN(max.getResult()));
        max.increment(testArray[0]);
        assertEquals(0d, max.getResult(), 0);
        max.increment(testArray[1]);
        assertEquals(0d, max.getResult(), 0);
        max.increment(testArray[2]);
        assertEquals(0d, max.getResult(), 0);
        max.increment(testArray[3]);
        assertEquals(Double.POSITIVE_INFINITY, max.getResult(), 0);
        assertEquals(Double.POSITIVE_INFINITY, max.evaluate(testArray), 0);     
    }

    public void testNaNs() {
        Max max = new Max();
        double nan = Double.NaN;
        assertEquals(3d, max.evaluate(new double[]{nan, 2d, 3d}), 0);     
        assertEquals(3d, max.evaluate(new double[]{1d, nan, 3d}), 0);     
        assertEquals(2d, max.evaluate(new double[]{1d, 2d, nan}), 0);     
        assertTrue(Double.isNaN(max.evaluate(new double[]{nan, nan, nan})));     
    }

}