/**
* 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.clustering.dirichlet;
import java.io.IOException;
import java.util.List;
import com.google.common.collect.Lists;
import org.apache.hadoop.conf.Configuration;
import org.apache.hadoop.fs.Path;
import org.apache.hadoop.io.IntWritable;
import org.apache.hadoop.io.WritableComparable;
import org.apache.hadoop.mapreduce.Mapper;
import org.apache.mahout.clustering.WeightedVectorWritable;
import org.apache.mahout.common.iterator.sequencefile.PathFilters;
import org.apache.mahout.common.iterator.sequencefile.PathType;
import org.apache.mahout.common.iterator.sequencefile.SequenceFileDirValueIterable;
import org.apache.mahout.math.VectorWritable;
public class DirichletClusterMapper
extends Mapper<WritableComparable<?>, VectorWritable, IntWritable, WeightedVectorWritable> {
private List<DirichletCluster> clusters;
private DirichletClusterer clusterer;
@Override
protected void map(WritableComparable<?> key, VectorWritable vector, Context context)
throws IOException, InterruptedException {
clusterer.emitPointToClusters(vector, clusters, context);
}
@Override
protected void setup(Context context) throws IOException, InterruptedException {
super.setup(context);
Configuration conf = context.getConfiguration();
clusters = getClusters(conf);
for (DirichletCluster cluster : clusters) {
cluster.getModel().configure(conf);
}
String emitMostLikely = conf.get(DirichletDriver.EMIT_MOST_LIKELY_KEY);
String threshold = conf.get(DirichletDriver.THRESHOLD_KEY);
clusterer = new DirichletClusterer(Boolean.parseBoolean(emitMostLikely), Double.parseDouble(threshold));
}
public static List<DirichletCluster> getClusters(Configuration conf) {
String statePath = conf.get(DirichletDriver.STATE_IN_KEY);
return loadClusters(conf, new Path(statePath));
}
protected static List<DirichletCluster> loadClusters(Configuration conf, Path stateIn) {
List<DirichletCluster> clusters = Lists.newArrayList();
for (DirichletCluster value
: new SequenceFileDirValueIterable<DirichletCluster>(stateIn,
PathType.LIST,
PathFilters.logsCRCFilter(),
conf)) {
clusters.add(value);
}
return clusters;
}
}