org.jenetics.stat.MinMaxTest.java Source code

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Here is the source code for org.jenetics.stat.MinMaxTest.java

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/*
 * Java Genetic Algorithm Library (@__identifier__@).
 * Copyright (c) @__year__@ Franz Wilhelmsttter
 *
 * Licensed 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.
 *
 * Author:
 *    Franz Wilhelmsttter (franz.wilhelmstoetter@gmx.at)
 */
package org.jenetics.stat;

import java.util.Arrays;
import java.util.Comparator;
import java.util.Random;
import java.util.stream.IntStream;
import java.util.stream.Stream;

import org.apache.commons.math3.stat.StatUtils;
import org.testng.Assert;
import org.testng.annotations.DataProvider;
import org.testng.annotations.Test;

import org.jenetics.internal.util.Named;

import org.jenetics.Optimize;
import org.jenetics.util.RandomRegistry;

/**
 * @author <a href="mailto:franz.wilhelmstoetter@gmx.at">Franz Wilhelmsttter</a>
 */
public class MinMaxTest {

    private static final Named<Comparator<Integer>> NORMAL = Named.of("NORMAL",
            (Comparator<Integer>) Optimize.MAXIMUM::compare);

    private static final Named<Comparator<Integer>> REVERSE = Named.of("REVERSE",
            (Comparator<Integer>) Optimize.MINIMUM::compare);

    @Test(dataProvider = "minTestValues")
    public void min(final Named<Comparator<Integer>> comparator, final Integer a, final Integer b,
            final Integer min) {
        Assert.assertEquals(MinMax.min(comparator.value, a, b), min);
    }

    @DataProvider(name = "minTestValues")
    public Object[][] minTestValues() {
        return new Object[][] { { NORMAL, null, null, null }, { NORMAL, null, 1, 1 }, { NORMAL, 1, null, 1 },
                { NORMAL, 1, 2, 1 }, { NORMAL, 2, 1, 1 }, { NORMAL, 1, 1, 1 },

                { REVERSE, null, null, null }, { REVERSE, null, 2, 2 }, { REVERSE, 2, null, 2 },
                { REVERSE, 1, 2, 2 }, { REVERSE, 2, 1, 2 }, { REVERSE, 2, 2, 2 } };
    }

    @Test(dataProvider = "maxTestValues")
    public void max(final Named<Comparator<Integer>> comparator, final Integer a, final Integer b,
            final Integer max) {
        Assert.assertEquals(MinMax.max(comparator.value, a, b), max);
    }

    @DataProvider(name = "maxTestValues")
    public Object[][] maxTestValues() {
        return new Object[][] { { NORMAL, null, null, null }, { NORMAL, null, 1, 1 }, { NORMAL, 1, null, 1 },
                { NORMAL, 1, 2, 2 }, { NORMAL, 2, 1, 2 }, { NORMAL, 1, 1, 1 },

                { REVERSE, null, null, null }, { REVERSE, null, 2, 2 }, { REVERSE, 2, null, 2 },
                { REVERSE, 1, 2, 1 }, { REVERSE, 2, 1, 1 }, { REVERSE, 2, 2, 2 } };
    }

    @Test
    public void acceptNormalMinMax() {
        final Random random = RandomRegistry.getRandom();
        final double[] numbers = random.doubles().limit(1000).toArray();

        final MinMax<Double> minMax = MinMax.of();
        Arrays.stream(numbers).mapToObj(Double::new).forEach(minMax);

        Assert.assertEquals(minMax.getMin(), StatUtils.min(numbers));
        Assert.assertEquals(minMax.getMax(), StatUtils.max(numbers));
    }

    @Test
    public void acceptReverseMinMax() {
        final Random random = RandomRegistry.getRandom();
        final double[] numbers = random.doubles().limit(1000).toArray();

        final MinMax<Double> minMax = MinMax.of((a, b) -> b.compareTo(a));
        Arrays.stream(numbers).mapToObj(Double::new).forEach(minMax);

        Assert.assertEquals(minMax.getMin(), StatUtils.max(numbers));
        Assert.assertEquals(minMax.getMax(), StatUtils.min(numbers));
    }

    @Test
    public void toMinMaxNormal() {
        final Random random = RandomRegistry.getRandom();
        final double[] numbers = random.doubles().limit(1000).toArray();

        final MinMax<Double> minMax = Arrays.stream(numbers).mapToObj(Double::new).collect(MinMax.toMinMax());

        Assert.assertEquals(minMax.getMin(), StatUtils.min(numbers));
        Assert.assertEquals(minMax.getMax(), StatUtils.max(numbers));
    }

    @Test
    public void toMinMaxReverse() {
        final Random random = RandomRegistry.getRandom();
        final double[] numbers = random.doubles().limit(1000).toArray();

        final MinMax<Double> minMax = Arrays.stream(numbers).mapToObj(Double::new)
                .collect(MinMax.toMinMax((a, b) -> b.compareTo(a)));

        Assert.assertEquals(minMax.getMin(), StatUtils.max(numbers));
        Assert.assertEquals(minMax.getMax(), StatUtils.min(numbers));
    }

    @Test
    public void parallelMinMax() {
        final Stream<Integer> stream = IntStream.range(0, 100).boxed().parallel();
        final MinMax<Integer> minMax = stream.collect(MinMax::of, MinMax::accept, MinMax::combine);

        Assert.assertEquals(minMax.getMax(), Integer.valueOf(99));
        Assert.assertEquals(minMax.getMin(), Integer.valueOf(0));
        Assert.assertEquals(100, minMax.getCount());
    }

}