/**
* 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.ga.watchmaker.cd.hadoop;
import java.util.List;
import java.util.Random;
import java.util.Set;
import com.google.common.collect.Lists;
import org.apache.hadoop.conf.Configuration;
import org.apache.hadoop.io.LongWritable;
import org.apache.hadoop.mapreduce.Reducer;
import org.apache.mahout.common.DummyRecordWriter;
import org.apache.mahout.common.RandomUtils;
import org.apache.mahout.examples.MahoutTestCase;
import org.apache.mahout.ga.watchmaker.cd.CDFitness;
import org.junit.Before;
import org.junit.Test;
public final class CDReducerTest extends MahoutTestCase {
private static final int NUM_EVALS = 100;
private List<CDFitness> evaluations;
private CDFitness expected;
@Override
@Before
public void setUp() throws Exception {
super.setUp();
// generate random evaluatons and calculate expectations
evaluations = Lists.newArrayList();
Random rng = RandomUtils.getRandom();
int tp = 0;
int fp = 0;
int tn = 0;
int fn = 0;
for (int index = 0; index < NUM_EVALS; index++) {
CDFitness fitness = new CDFitness(rng.nextInt(100), rng.nextInt(100), rng.nextInt(100), rng.nextInt(100));
tp += fitness.getTp();
fp += fitness.getFp();
tn += fitness.getTn();
fn += fitness.getFn();
evaluations.add(fitness);
}
expected = new CDFitness(tp, fp, tn, fn);
}
@Test
public void testReduce() throws Exception {
CDReducer reducer = new CDReducer();
Configuration conf = new Configuration();
DummyRecordWriter<LongWritable, CDFitness> reduceWriter = new DummyRecordWriter<LongWritable, CDFitness>();
Reducer<LongWritable, CDFitness, LongWritable, CDFitness>.Context reduceContext =
DummyRecordWriter.build(reducer, conf, reduceWriter, LongWritable.class, CDFitness.class);
LongWritable zero = new LongWritable(0);
reducer.reduce(zero, evaluations, reduceContext);
// check if the expectations are met
Set<LongWritable> keys = reduceWriter.getKeys();
assertEquals("nb keys", 1, keys.size());
assertTrue("bad key", keys.contains(zero));
assertEquals("nb values", 1, reduceWriter.getValue(zero).size());
CDFitness fitness = reduceWriter.getValue(zero).get(0);
assertEquals(expected, fitness);
}
}