/**
* 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.cf.taste.hadoop.preparation;
import org.apache.hadoop.io.IntWritable;
import org.apache.hadoop.mapreduce.Reducer;
import org.apache.mahout.math.VectorWritable;
import java.io.IOException;
public class ToItemVectorsReducer extends Reducer<IntWritable,VectorWritable,IntWritable,VectorWritable> {
@Override
protected void reduce(IntWritable row, Iterable<VectorWritable> vectors, Context ctx)
throws IOException, InterruptedException {
VectorWritable vectorWritable = VectorWritable.merge(vectors.iterator());
vectorWritable.setWritesLaxPrecision(true);
ctx.write(row, vectorWritable);
}
}