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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 * limitations under the License. */ /** * <p>Provides IEEE-754r variants of NumberUtils methods. </p> * * <p>See: <a href="http://en.wikipedia.org/wiki/IEEE_754r">http://en.wikipedia.org/wiki/IEEE_754r</a></p> * * @since 2.4 * @version $Id: IEEE754rUtils.java 634088 2008-03-06 00:06:05Z niallp $ */ public class IEEE754rUtils { /** * <p>Returns the minimum value in an array.</p> * * @param array an array, must not be null or empty * @return the minimum value in the array * @throws IllegalArgumentException if <code>array</code> is <code>null</code> * @throws IllegalArgumentException if <code>array</code> is empty */ public static double min(double[] array) { // Validates input if (array == null) { throw new IllegalArgumentException("The Array must not be null"); } else if (array.length == 0) { throw new IllegalArgumentException("Array cannot be empty."); } // Finds and returns min double min = array[0]; for (int i = 1; i < array.length; i++) { min = min(array[i], min); } return min; } /** * <p>Returns the minimum value in an array.</p> * * @param array an array, must not be null or empty * @return the minimum value in the array * @throws IllegalArgumentException if <code>array</code> is <code>null</code> * @throws IllegalArgumentException if <code>array</code> is empty */ public static float min(float[] array) { // Validates input if (array == null) { throw new IllegalArgumentException("The Array must not be null"); } else if (array.length == 0) { throw new IllegalArgumentException("Array cannot be empty."); } // Finds and returns min float min = array[0]; for (int i = 1; i < array.length; i++) { min = min(array[i], min); } return min; } /** * <p>Gets the minimum of three <code>double</code> values.</p> * * <p>NaN is only returned if all numbers are NaN as per IEEE-754r. </p> * * @param a value 1 * @param b value 2 * @param c value 3 * @return the smallest of the values */ public static double min(double a, double b, double c) { return min(min(a, b), c); } /** * <p>Gets the minimum of two <code>double</code> values.</p> * * <p>NaN is only returned if all numbers are NaN as per IEEE-754r. </p> * * @param a value 1 * @param b value 2 * @return the smallest of the values */ public static double min(double a, double b) { if (Double.isNaN(a)) { return b; } else if (Double.isNaN(b)) { return a; } else { return Math.min(a, b); } } /** * <p>Gets the minimum of three <code>float</code> values.</p> * * <p>NaN is only returned if all numbers are NaN as per IEEE-754r. </p> * * @param a value 1 * @param b value 2 * @param c value 3 * @return the smallest of the values */ public static float min(float a, float b, float c) { return min(min(a, b), c); } /** * <p>Gets the minimum of two <code>float</code> values.</p> * * <p>NaN is only returned if all numbers are NaN as per IEEE-754r. </p> * * @param a value 1 * @param b value 2 * @return the smallest of the values */ public static float min(float a, float b) { if (Float.isNaN(a)) { return b; } else if (Float.isNaN(b)) { return a; } else { return Math.min(a, b); } } /** * <p>Returns the maximum value in an array.</p> * * @param array an array, must not be null or empty * @return the minimum value in the array * @throws IllegalArgumentException if <code>array</code> is <code>null</code> * @throws IllegalArgumentException if <code>array</code> is empty */ public static double max(double[] array) { // Validates input if (array == null) { throw new IllegalArgumentException("The Array must not be null"); } else if (array.length == 0) { throw new IllegalArgumentException("Array cannot be empty."); } // Finds and returns max double max = array[0]; for (int j = 1; j < array.length; j++) { max = max(array[j], max); } return max; } /** * <p>Returns the maximum value in an array.</p> * * @param array an array, must not be null or empty * @return the minimum value in the array * @throws IllegalArgumentException if <code>array</code> is <code>null</code> * @throws IllegalArgumentException if <code>array</code> is empty */ public static float max(float[] array) { // Validates input if (array == null) { throw new IllegalArgumentException("The Array must not be null"); } else if (array.length == 0) { throw new IllegalArgumentException("Array cannot be empty."); } // Finds and returns max float max = array[0]; for (int j = 1; j < array.length; j++) { max = max(array[j], max); } return max; } /** * <p>Gets the maximum of three <code>double</code> values.</p> * * <p>NaN is only returned if all numbers are NaN as per IEEE-754r. </p> * * @param a value 1 * @param b value 2 * @param c value 3 * @return the largest of the values */ public static double max(double a, double b, double c) { return max(max(a, b), c); } /** * <p>Gets the maximum of two <code>double</code> values.</p> * * <p>NaN is only returned if all numbers are NaN as per IEEE-754r. </p> * * @param a value 1 * @param b value 2 * @return the largest of the values */ public static double max(double a, double b) { if (Double.isNaN(a)) { return b; } else if (Double.isNaN(b)) { return a; } else { return Math.max(a, b); } } /** * <p>Gets the maximum of three <code>float</code> values.</p> * * <p>NaN is only returned if all numbers are NaN as per IEEE-754r. </p> * * @param a value 1 * @param b value 2 * @param c value 3 * @return the largest of the values */ public static float max(float a, float b, float c) { return max(max(a, b), c); } /** * <p>Gets the maximum of two <code>float</code> values.</p> * * <p>NaN is only returned if all numbers are NaN as per IEEE-754r. </p> * * @param a value 1 * @param b value 2 * @return the largest of the values */ public static float max(float a, float b) { if (Float.isNaN(a)) { return b; } else if (Float.isNaN(b)) { return a; } else { return Math.max(a, b); } } }