org.apache.mahout.math.VectorWritableTest.java Source code

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Here is the source code for org.apache.mahout.math.VectorWritableTest.java

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/**
 * 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.mahout.math;

import java.io.ByteArrayInputStream;
import java.io.ByteArrayOutputStream;
import java.io.DataInputStream;
import java.io.DataOutputStream;
import java.io.IOException;

import org.apache.hadoop.io.Writable;
import org.apache.mahout.math.Vector.Element;
import org.junit.Test;

import com.carrotsearch.randomizedtesting.RandomizedTest;
import com.carrotsearch.randomizedtesting.annotations.Repeat;
import com.google.common.io.Closeables;

public final class VectorWritableTest extends RandomizedTest {
    private static final int MAX_VECTOR_SIZE = 100;

    public void createRandom(Vector v) {
        int size = randomInt(v.size() - 1);
        for (int i = 0; i < size; ++i) {
            v.set(randomInt(v.size() - 1), randomDouble());
        }

        int zeros = Math.max(2, size / 4);
        for (Element e : v.nonZeroes()) {
            if (e.index() % zeros == 0) {
                e.set(0.0);
            }
        }
    }

    @Test
    @Repeat(iterations = 20)
    public void testViewSequentialAccessSparseVectorWritable() throws Exception {
        Vector v = new SequentialAccessSparseVector(MAX_VECTOR_SIZE);
        createRandom(v);
        Vector view = new VectorView(v, 0, v.size());
        doTestVectorWritableEquals(view);
    }

    @Test
    @Repeat(iterations = 20)
    public void testSequentialAccessSparseVectorWritable() throws Exception {
        Vector v = new SequentialAccessSparseVector(MAX_VECTOR_SIZE);
        createRandom(v);
        doTestVectorWritableEquals(v);
    }

    @Test
    @Repeat(iterations = 20)
    public void testRandomAccessSparseVectorWritable() throws Exception {
        Vector v = new RandomAccessSparseVector(MAX_VECTOR_SIZE);
        createRandom(v);
        doTestVectorWritableEquals(v);
    }

    @Test
    @Repeat(iterations = 20)
    public void testDenseVectorWritable() throws Exception {
        Vector v = new DenseVector(MAX_VECTOR_SIZE);
        createRandom(v);
        doTestVectorWritableEquals(v);
    }

    @Test
    @Repeat(iterations = 20)
    public void testNamedVectorWritable() throws Exception {
        Vector v = new DenseVector(MAX_VECTOR_SIZE);
        v = new NamedVector(v, "Victor");
        createRandom(v);
        doTestVectorWritableEquals(v);
    }

    private static void doTestVectorWritableEquals(Vector v) throws IOException {
        Writable vectorWritable = new VectorWritable(v);
        VectorWritable vectorWritable2 = new VectorWritable();
        writeAndRead(vectorWritable, vectorWritable2);
        Vector v2 = vectorWritable2.get();
        if (v instanceof NamedVector) {
            assertTrue(v2 instanceof NamedVector);
            NamedVector nv = (NamedVector) v;
            NamedVector nv2 = (NamedVector) v2;
            assertEquals(nv.getName(), nv2.getName());
            assertEquals("Victor", nv.getName());
        }
        assertEquals(v, v2);
    }

    private static void writeAndRead(Writable toWrite, Writable toRead) throws IOException {
        ByteArrayOutputStream baos = new ByteArrayOutputStream();
        DataOutputStream dos = new DataOutputStream(baos);
        try {
            toWrite.write(dos);
        } finally {
            Closeables.close(dos, false);
        }

        ByteArrayInputStream bais = new ByteArrayInputStream(baos.toByteArray());
        DataInputStream dis = new DataInputStream(bais);
        try {
            toRead.readFields(dis);
        } finally {
            Closeables.close(dos, true);
        }
    }
}