/**
* 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.stats.entropy;
import org.apache.hadoop.io.Text;
import org.apache.hadoop.mapreduce.Mapper;
import org.apache.mahout.common.StringTuple;
import org.apache.mahout.math.VarIntWritable;
import java.io.IOException;
/**
* Converts the key from {@link StringTuple} with values [key, value] to {@link Text} with value key.
*/
public class SpecificConditionalEntropyMapper extends Mapper<StringTuple, VarIntWritable, Text, VarIntWritable> {
private final Text resultKey = new Text();
@Override
protected void map(StringTuple key, VarIntWritable value, Context context)
throws IOException, InterruptedException {
resultKey.set(key.stringAt(0));
context.write(resultKey, value);
}
}