| /* |
| * 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.math.stat.descriptive; |
| |
| import org.apache.commons.math.MathRuntimeException; |
| import org.apache.commons.math.exception.DimensionMismatchException; |
| import org.apache.commons.math.exception.NotPositiveException; |
| import org.apache.commons.math.exception.NullArgumentException; |
| import org.apache.commons.math.exception.util.LocalizedFormats; |
| |
| /** |
| * Abstract base class for all implementations of the |
| * {@link UnivariateStatistic} interface. |
| * <p> |
| * Provides a default implementation of <code>evaluate(double[]),</code> |
| * delegating to <code>evaluate(double[], int, int)</code> in the natural way. |
| * </p> |
| * <p> |
| * Also includes a <code>test</code> method that performs generic parameter |
| * validation for the <code>evaluate</code> methods.</p> |
| * |
| * @version $Revision: 1006299 $ $Date: 2010-10-10 16:47:17 +0200 (dim. 10 oct. 2010) $ |
| */ |
| public abstract class AbstractUnivariateStatistic |
| implements UnivariateStatistic { |
| |
| /** Stored data. */ |
| private double[] storedData; |
| |
| /** |
| * Set the data array. |
| * <p> |
| * The stored value is a copy of the parameter array, not the array itself |
| * </p> |
| * @param values data array to store (may be null to remove stored data) |
| * @see #evaluate() |
| */ |
| public void setData(final double[] values) { |
| storedData = (values == null) ? null : values.clone(); |
| } |
| |
| /** |
| * Get a copy of the stored data array. |
| * @return copy of the stored data array (may be null) |
| */ |
| public double[] getData() { |
| return (storedData == null) ? null : storedData.clone(); |
| } |
| |
| /** |
| * Get a reference to the stored data array. |
| * @return reference to the stored data array (may be null) |
| */ |
| protected double[] getDataRef() { |
| return storedData; |
| } |
| |
| /** |
| * Set the data array. |
| * @param values data array to store |
| * @param begin the index of the first element to include |
| * @param length the number of elements to include |
| * @see #evaluate() |
| */ |
| public void setData(final double[] values, final int begin, final int length) { |
| storedData = new double[length]; |
| System.arraycopy(values, begin, storedData, 0, length); |
| } |
| |
| /** |
| * Returns the result of evaluating the statistic over the stored data. |
| * <p> |
| * The stored array is the one which was set by previous calls to |
| * </p> |
| * @return the value of the statistic applied to the stored data |
| */ |
| public double evaluate() { |
| return evaluate(storedData); |
| } |
| |
| /** |
| * {@inheritDoc} |
| */ |
| public double evaluate(final double[] values) { |
| test(values, 0, 0); |
| return evaluate(values, 0, values.length); |
| } |
| |
| /** |
| * {@inheritDoc} |
| */ |
| public abstract double evaluate(final double[] values, final int begin, final int length); |
| |
| /** |
| * {@inheritDoc} |
| */ |
| public abstract UnivariateStatistic copy(); |
| |
| /** |
| * This method is used by <code>evaluate(double[], int, int)</code> methods |
| * to verify that the input parameters designate a subarray of positive length. |
| * <p> |
| * <ul> |
| * <li>returns <code>true</code> iff the parameters designate a subarray of |
| * positive length</li> |
| * <li>throws <code>IllegalArgumentException</code> if the array is null or |
| * or the indices are invalid</li> |
| * <li>returns <code>false</li> if the array is non-null, but |
| * <code>length</code> is 0. |
| * </ul></p> |
| * |
| * @param values the input array |
| * @param begin index of the first array element to include |
| * @param length the number of elements to include |
| * @return true if the parameters are valid and designate a subarray of positive length |
| * @throws IllegalArgumentException if the indices are invalid or the array is null |
| */ |
| protected boolean test( |
| final double[] values, |
| final int begin, |
| final int length) { |
| |
| if (values == null) { |
| throw new NullArgumentException(LocalizedFormats.INPUT_ARRAY); |
| } |
| |
| if (begin < 0) { |
| throw new NotPositiveException(LocalizedFormats.START_POSITION, begin); |
| } |
| |
| if (length < 0) { |
| throw new NotPositiveException(LocalizedFormats.LENGTH, length); |
| } |
| |
| if (begin + length > values.length) { |
| throw MathRuntimeException.createIllegalArgumentException( |
| LocalizedFormats.SUBARRAY_ENDS_AFTER_ARRAY_END); |
| } |
| |
| if (length == 0) { |
| return false; |
| } |
| |
| return true; |
| |
| } |
| |
| /** |
| * This method is used by <code>evaluate(double[], double[], int, int)</code> methods |
| * to verify that the begin and length parameters designate a subarray of positive length |
| * and the weights are all non-negative, non-NaN, finite, and not all zero. |
| * <p> |
| * <ul> |
| * <li>returns <code>true</code> iff the parameters designate a subarray of |
| * positive length and the weights array contains legitimate values.</li> |
| * <li>throws <code>IllegalArgumentException</code> if any of the following are true: |
| * <ul><li>the values array is null</li> |
| * <li>the weights array is null</li> |
| * <li>the weights array does not have the same length as the values array</li> |
| * <li>the weights array contains one or more infinite values</li> |
| * <li>the weights array contains one or more NaN values</li> |
| * <li>the weights array contains negative values</li> |
| * <li>the start and length arguments do not determine a valid array</li></ul> |
| * </li> |
| * <li>returns <code>false</li> if the array is non-null, but |
| * <code>length</code> is 0. |
| * </ul></p> |
| * |
| * @param values the input array |
| * @param weights the weights array |
| * @param begin index of the first array element to include |
| * @param length the number of elements to include |
| * @return true if the parameters are valid and designate a subarray of positive length |
| * @throws IllegalArgumentException if the indices are invalid or the array is null |
| * @since 2.1 |
| */ |
| protected boolean test( |
| final double[] values, |
| final double[] weights, |
| final int begin, |
| final int length) { |
| |
| if (weights == null) { |
| throw new NullArgumentException(LocalizedFormats.INPUT_ARRAY); |
| } |
| |
| if (weights.length != values.length) { |
| throw new DimensionMismatchException(weights.length, values.length); |
| } |
| |
| boolean containsPositiveWeight = false; |
| for (int i = begin; i < begin + length; i++) { |
| if (Double.isNaN(weights[i])) { |
| throw MathRuntimeException.createIllegalArgumentException( |
| LocalizedFormats.NAN_ELEMENT_AT_INDEX, i); |
| } |
| if (Double.isInfinite(weights[i])) { |
| throw MathRuntimeException.createIllegalArgumentException( |
| LocalizedFormats.INFINITE_ARRAY_ELEMENT, weights[i], i); |
| } |
| if (weights[i] < 0) { |
| throw MathRuntimeException.createIllegalArgumentException( |
| LocalizedFormats.NEGATIVE_ELEMENT_AT_INDEX, i, weights[i]); |
| } |
| if (!containsPositiveWeight && weights[i] > 0.0) { |
| containsPositiveWeight = true; |
| } |
| } |
| |
| if (!containsPositiveWeight) { |
| throw MathRuntimeException.createIllegalArgumentException( |
| LocalizedFormats.WEIGHT_AT_LEAST_ONE_NON_ZERO); |
| } |
| |
| return test(values, begin, length); |
| } |
| } |
| |