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A collection of user-defined functions for working with large-scale data in Hadoop and Pig.

There is a newer version: 1.2.0

/*
 * Copyright 2012 LinkedIn, Inc
 * 
 * Licensed 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 datafu.pig.stats;

/**
 * Computes the approximate {@link median} 
 * for a (not necessarily sorted) input bag, using the Munro-Paterson algorithm.  
 * This is a convenience wrapper around StreamingQuantile.
 *
 * 
 * N.B., all the data is pushed to a single reducer per key, so make sure some partitioning is 
 * done (e.g., group by 'day') if the data is too large.  That is, this isn't distributed median.
 * 
 * 
 * @see StreamingQuantile
 */
public class StreamingMedian extends StreamingQuantile
{
  public StreamingMedian()
  {
    super("0.5");
  }
}