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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
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package org.apache.commons.math3.stat.ranking;

Interface representing a rank transformation.
Since:
2.0/**
 * Interface representing a rank transformation.
 *
 * @since 2.0
 */
public interface RankingAlgorithm {
    
Performs a rank transformation on the input data, returning an array
of ranks.
Ranks should be 1-based - that is, the smallest value
returned in an array of ranks should be greater than or equal to one,
rather than 0. Ranks should in general take integer values, though
implementations may return averages or other floating point values
to resolve ties in the input data.
Params:
data – array of data to be ranked
Returns:
an array of ranks corresponding to the elements of the input array/**
     * <p>Performs a rank transformation on the input data, returning an array
     * of ranks.</p>
     *
     * <p>Ranks should be 1-based - that is, the smallest value
     * returned in an array of ranks should be greater than or equal to one,
     * rather than 0. Ranks should in general take integer values, though
     * implementations may return averages or other floating point values
     * to resolve ties in the input data.</p>
     *
     * @param data array of data to be ranked
     * @return an array of ranks corresponding to the elements of the input array
     */
    double[] rank (double[] data);
}