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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
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*/
/**
* Pig UDFs for Tuple sketches.
* Tuple sketches are based on the idea of Theta sketches with the addition of
* values associated with unique keys.
* Two sets of tuple sketch classes are available at the moment:
* generic Tuple sketches with user-defined Summary, and a faster specialized
* implementation with an array of double values.
*
* <p>There are two sets of Pig UDFs: one for generic Tuple sketch with an example
* implementation for DoubleSummay, and another one for a specialized ArrayOfDoublesSketch.
*
* <p> The generic implementation is in the form of abstract classes DataToSketch and
* UnionSketch to be specialized for particular types of Summary.
* An example implementation for DoubleSumamry is provided: DataToDoubleSummarySketch and
* UnionDoubleSummarySketch, as well as UDFs to obtain the results from sketches:
* DoubleSumamrySketchToEstimates and DoubleSummarySketchToPercentile.
*
* <p>UDFs for ArrayOfDoublesSketch: DataToArrayOfDoublesSketch, UnionArrayOfDoublesSketch,
* ArrayOfDoublesSketchToEstimates.
*
* @author Alexander Saydakov
*/
package org.apache.datasketches.pig.tuple;