/**
* 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.df.mapred;
import org.apache.commons.cli2.CommandLine;
import org.apache.commons.cli2.Group;
import org.apache.commons.cli2.Option;
import org.apache.commons.cli2.OptionException;
import org.apache.commons.cli2.builder.ArgumentBuilder;
import org.apache.commons.cli2.builder.DefaultOptionBuilder;
import org.apache.commons.cli2.builder.GroupBuilder;
import org.apache.commons.cli2.commandline.Parser;
import org.apache.hadoop.conf.Configuration;
import org.apache.hadoop.conf.Configured;
import org.apache.hadoop.fs.FileSystem;
import org.apache.hadoop.fs.Path;
import org.apache.hadoop.util.Tool;
import org.apache.hadoop.util.ToolRunner;
import org.apache.mahout.common.CommandLineUtil;
import org.apache.mahout.df.DFUtils;
import org.apache.mahout.df.DecisionForest;
import org.apache.mahout.df.ErrorEstimate;
import org.apache.mahout.df.builder.DefaultTreeBuilder;
import org.apache.mahout.df.callback.ForestPredictions;
import org.apache.mahout.df.data.Data;
import org.apache.mahout.df.data.DataLoader;
import org.apache.mahout.df.data.Dataset;
import org.apache.mahout.df.mapred.inmem.InMemBuilder;
import org.apache.mahout.df.mapred.partial.PartialBuilder;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;
import java.io.IOException;
import java.util.Random;
/**
* Tool to builds a Random Forest using any given dataset (in UCI format). Can
* use either the in-mem mapred or partial mapred implementations
*/
public class BuildForest extends Configured implements Tool {
private static final Logger log = LoggerFactory.getLogger(BuildForest.class);
private Path dataPath; // Data path
private Path datasetPath; // Dataset path
private int m; // Number of variables to select at each tree-node
private int nbTrees; // Number of trees to grow
private Long seed = null; // Random seed
private boolean isPartial; // use partial data implementation
private boolean isOob; // estimate oob error;
@Override
public int run(String[] args) throws IOException {
DefaultOptionBuilder obuilder = new DefaultOptionBuilder();
ArgumentBuilder abuilder = new ArgumentBuilder();
GroupBuilder gbuilder = new GroupBuilder();
Option oobOpt = obuilder.withShortName("oob").withRequired(false)
.withDescription("Optional, estimate the out-of-bag error").create();
Option dataOpt = obuilder.withLongName("data").withShortName("d")
.withRequired(true).withArgument(
abuilder.withName("path").withMinimum(1).withMaximum(1).create())
.withDescription("Data path").create();
Option datasetOpt = obuilder.withLongName("dataset").withShortName("ds").withRequired(true)
.withArgument(abuilder.withName("dataset").withMinimum(1).withMaximum(1).create())
.withDescription("Dataset path").create();
Option selectionOpt = obuilder.withLongName("selection")
.withShortName("sl").withRequired(true).withArgument(
abuilder.withName("m").withMinimum(1).withMaximum(1).create())
.withDescription("Number of variables to select randomly at each tree-node")
.create();
Option seedOpt = obuilder.withLongName("seed").withShortName("sd").withRequired(false)
.withArgument(abuilder.withName("seed").withMinimum(1).withMaximum(1).create())
.withDescription("Optional, seed value used to initialise the Random number generator")
.create();
Option partialOpt = obuilder.withLongName("partial").withShortName("p")
.withRequired(false).withDescription("Optional, use the Partial Data implementation").create();
Option nbtreesOpt = obuilder.withLongName("nbtrees").withShortName("t").withRequired(true)
.withArgument(abuilder.withName("nbtrees").withMinimum(1).withMaximum(1).create())
.withDescription("Number of trees to grow").create();
Option helpOpt = obuilder.withLongName("help").withDescription(
"Print out help").withShortName("h").create();
Group group = gbuilder.withName("Options").withOption(oobOpt).withOption(
dataOpt).withOption(datasetOpt).withOption(selectionOpt).withOption(
seedOpt).withOption(partialOpt).withOption(nbtreesOpt).withOption(
helpOpt).create();
try {
Parser parser = new Parser();
parser.setGroup(group);
CommandLine cmdLine = parser.parse(args);
if (cmdLine.hasOption("help")) {
CommandLineUtil.printHelp(group);
return -1;
}
isPartial = cmdLine.hasOption(partialOpt);
isOob = cmdLine.hasOption(oobOpt);
String dataName = cmdLine.getValue(dataOpt).toString();
String datasetName = cmdLine.getValue(datasetOpt).toString();
m = Integer.parseInt(cmdLine.getValue(selectionOpt).toString());
nbTrees = Integer.parseInt(cmdLine.getValue(nbtreesOpt).toString());
if (cmdLine.hasOption(seedOpt)) {
seed = Long.valueOf(cmdLine.getValue(seedOpt).toString());
}
log.debug("data : " + dataName);
log.debug("dataset : " + datasetName);
log.debug("m : " + m);
log.debug("seed : " + seed);
log.debug("nbtrees : " + nbTrees);
log.debug("isPartial : " + isPartial);
log.debug("isOob : " + isOob);
dataPath = new Path(dataName);
datasetPath = new Path(datasetName);
} catch (OptionException e) {
System.err.println("Exception : " + e);
CommandLineUtil.printHelp(group);
return -1;
}
buildForest();
return 0;
}
private DecisionForest buildForest() throws IOException {
DefaultTreeBuilder treeBuilder = new DefaultTreeBuilder();
treeBuilder.setM(m);
Dataset dataset = Dataset.load(getConf(), datasetPath);
ForestPredictions callback = (isOob) ? new ForestPredictions(dataset
.nbInstances(), dataset.nblabels()) : null;
Builder forestBuilder;
if (isPartial) {
log.info("Partial Mapred implementation");
forestBuilder = new PartialBuilder(treeBuilder, dataPath, datasetPath,
seed, getConf());
} else {
log.info("InMem Mapred implementation");
forestBuilder = new InMemBuilder(treeBuilder, dataPath, datasetPath,
seed, getConf());
}
log.info("Building the forest...");
long time = System.currentTimeMillis();
DecisionForest forest = forestBuilder.build(nbTrees, callback);
time = System.currentTimeMillis() - time;
log.info("Build Time: " + DFUtils.elapsedTime(time));
if (isOob) {
Random rng;
if (seed != null)
rng = new Random(seed);
else
rng = new Random();
FileSystem fs = dataPath.getFileSystem(getConf());
int[] labels = Data.extractLabels(dataset, fs, dataPath);
log.info("oob error estimate : "
+ ErrorEstimate.errorRate(labels, callback.computePredictions(rng)));
}
return forest;
}
protected static Data loadData(Configuration conf, Path dataPath, Dataset dataset)
throws Exception {
log.info("Loading the data...");
FileSystem fs = dataPath.getFileSystem(conf);
Data data = DataLoader.loadData(dataset, fs, dataPath);
log.info("Data Loaded");
return data;
}
/**
* @param args
* @throws Exception
*/
public static void main(String[] args) throws Exception {
ToolRunner.run(new Configuration(), new BuildForest(), args);
}
}