org.apache.mahout.classifier.df.tools.Frequencies.java Source code

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Here is the source code for org.apache.mahout.classifier.df.tools.Frequencies.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.classifier.df.tools;

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.slf4j.Logger;
import org.slf4j.LoggerFactory;

import java.io.IOException;
import java.util.Arrays;

/**
 * Compute the frequency distribution of the "class label"<br>
 * This class can be used when the criterion variable is the categorical attribute.
 */
public final class Frequencies extends Configured implements Tool {

    private static final Logger log = LoggerFactory.getLogger(Frequencies.class);

    private Frequencies() {
    }

    @Override
    public int run(String[] args) throws IOException, ClassNotFoundException, InterruptedException {

        DefaultOptionBuilder obuilder = new DefaultOptionBuilder();
        ArgumentBuilder abuilder = new ArgumentBuilder();
        GroupBuilder gbuilder = new GroupBuilder();

        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("path").withMinimum(1).create()).withDescription("dataset path")
                .create();

        Option helpOpt = obuilder.withLongName("help").withDescription("Print out help").withShortName("h")
                .create();

        Group group = gbuilder.withName("Options").withOption(dataOpt).withOption(datasetOpt).withOption(helpOpt)
                .create();

        try {
            Parser parser = new Parser();
            parser.setGroup(group);
            CommandLine cmdLine = parser.parse(args);

            if (cmdLine.hasOption(helpOpt)) {
                CommandLineUtil.printHelp(group);
                return 0;
            }

            String dataPath = cmdLine.getValue(dataOpt).toString();
            String datasetPath = cmdLine.getValue(datasetOpt).toString();

            log.debug("Data path : {}", dataPath);
            log.debug("Dataset path : {}", datasetPath);

            runTool(dataPath, datasetPath);
        } catch (OptionException e) {
            log.warn(e.toString(), e);
            CommandLineUtil.printHelp(group);
        }

        return 0;
    }

    private void runTool(String data, String dataset)
            throws IOException, ClassNotFoundException, InterruptedException {

        FileSystem fs = FileSystem.get(getConf());
        Path workingDir = fs.getWorkingDirectory();

        Path dataPath = new Path(data);
        Path datasetPath = new Path(dataset);

        log.info("Computing the frequencies...");
        FrequenciesJob job = new FrequenciesJob(new Path(workingDir, "output"), dataPath, datasetPath);

        int[][] counts = job.run(getConf());

        // outputing the frequencies
        log.info("counts[partition][class]");
        for (int[] count : counts) {
            log.info(Arrays.toString(count));
        }
    }

    public static void main(String[] args) throws Exception {
        ToolRunner.run(new Configuration(), new Frequencies(), args);
    }

}