| /* |
| * 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.commons.math4.legacy.stat.descriptive.rank; |
| |
| import org.apache.commons.math4.legacy.exception.MathIllegalArgumentException; |
| import org.apache.commons.math4.legacy.exception.NullArgumentException; |
| import org.apache.commons.math4.legacy.stat.ranking.NaNStrategy; |
| |
| |
| /** |
| * Returns the median of the available values. This is the same as the 50th percentile. |
| * See {@link Percentile} for a description of the algorithm used. |
| * <p> |
| * <strong>Note that this implementation is not synchronized.</strong> If |
| * multiple threads access an instance of this class concurrently, and at least |
| * one of the threads invokes the <code>increment()</code> or |
| * <code>clear()</code> method, it must be synchronized externally.</p> |
| */ |
| public class Median extends Percentile { |
| /** Fixed quantile. */ |
| private static final double FIXED_QUANTILE_50 = 50.0; |
| |
| /** |
| * Default constructor. |
| */ |
| public Median() { |
| // No try-catch or advertised exception - arg is valid |
| super(FIXED_QUANTILE_50); |
| } |
| |
| /** |
| * Copy constructor, creates a new {@code Median} identical. |
| * to the {@code original} |
| * |
| * @param original the {@code Median} instance to copy |
| * @throws NullArgumentException if original is null |
| */ |
| public Median(Median original) throws NullArgumentException { |
| super(original); |
| } |
| |
| /** |
| * Constructs a Median with the specific {@link EstimationType}, {@link NaNStrategy} and {@link KthSelector}. |
| * |
| * @param estimationType one of the percentile {@link EstimationType estimation types} |
| * @param nanStrategy one of {@link NaNStrategy} to handle with NaNs |
| * @param kthSelector {@link KthSelector} to use for pivoting during search |
| * @throws MathIllegalArgumentException if p is not within (0,100] |
| * @throws NullArgumentException if type or NaNStrategy passed is null |
| */ |
| private Median(final EstimationType estimationType, final NaNStrategy nanStrategy, |
| final KthSelector kthSelector) |
| throws MathIllegalArgumentException { |
| super(FIXED_QUANTILE_50, estimationType, nanStrategy, kthSelector); |
| } |
| |
| /** {@inheritDoc} */ |
| @Override |
| public Median withEstimationType(final EstimationType newEstimationType) { |
| return new Median(newEstimationType, getNaNStrategy(), getKthSelector()); |
| } |
| |
| /** {@inheritDoc} */ |
| @Override |
| public Median withNaNStrategy(final NaNStrategy newNaNStrategy) { |
| return new Median(getEstimationType(), newNaNStrategy, getKthSelector()); |
| } |
| |
| /** {@inheritDoc} */ |
| @Override |
| public Median withKthSelector(final KthSelector newKthSelector) { |
| return new Median(getEstimationType(), getNaNStrategy(), newKthSelector); |
| } |
| |
| } |