diff options
Diffstat (limited to 'src/main/java/org/apache/commons/math3/stat/descriptive/AbstractUnivariateStatistic.java')
| -rw-r--r-- | src/main/java/org/apache/commons/math3/stat/descriptive/AbstractUnivariateStatistic.java | 263 |
1 files changed, 263 insertions, 0 deletions
diff --git a/src/main/java/org/apache/commons/math3/stat/descriptive/AbstractUnivariateStatistic.java b/src/main/java/org/apache/commons/math3/stat/descriptive/AbstractUnivariateStatistic.java new file mode 100644 index 0000000..9abe45a --- /dev/null +++ b/src/main/java/org/apache/commons/math3/stat/descriptive/AbstractUnivariateStatistic.java @@ -0,0 +1,263 @@ +/* + * 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.math3.stat.descriptive; + +import org.apache.commons.math3.exception.NotPositiveException; +import org.apache.commons.math3.exception.NullArgumentException; +import org.apache.commons.math3.exception.NumberIsTooLargeException; +import org.apache.commons.math3.exception.MathIllegalArgumentException; +import org.apache.commons.math3.exception.util.LocalizedFormats; +import org.apache.commons.math3.util.MathArrays; + +/** + * 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> + * + */ +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. The input array is copied, not referenced. + * + * @param values data array to store + * @param begin the index of the first element to include + * @param length the number of elements to include + * @throws MathIllegalArgumentException if values is null or the indices + * are not valid + * @see #evaluate() + */ + public void setData(final double[] values, final int begin, final int length) + throws MathIllegalArgumentException { + 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 new NumberIsTooLargeException(LocalizedFormats.SUBARRAY_ENDS_AFTER_ARRAY_END, + begin + length, values.length, true); + } + 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 {@link #setData(double[])}. + * </p> + * @return the value of the statistic applied to the stored data + * @throws MathIllegalArgumentException if the stored data array is null + */ + public double evaluate() throws MathIllegalArgumentException { + return evaluate(storedData); + } + + /** + * {@inheritDoc} + */ + public double evaluate(final double[] values) throws MathIllegalArgumentException { + test(values, 0, 0); + return evaluate(values, 0, values.length); + } + + /** + * {@inheritDoc} + */ + public abstract double evaluate(final double[] values, final int begin, final int length) + throws MathIllegalArgumentException; + + /** + * {@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>MathIllegalArgumentException</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 MathIllegalArgumentException if the indices are invalid or the array is null + */ + protected boolean test( + final double[] values, + final int begin, + final int length) throws MathIllegalArgumentException { + return MathArrays.verifyValues(values, begin, length, false); + } + + /** + * 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 + * non-negative 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 unless <code>allowEmpty</code> is <code>true</code> + * </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 + * @param allowEmpty if <code>true</code> then zero length arrays are allowed + * @return true if the parameters are valid + * @throws MathIllegalArgumentException if the indices are invalid or the array is null + * @since 3.0 + */ + protected boolean test(final double[] values, final int begin, + final int length, final boolean allowEmpty) throws MathIllegalArgumentException { + return MathArrays.verifyValues(values, begin, length, allowEmpty); + } + + /** + * 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 MathIllegalArgumentException 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) throws MathIllegalArgumentException { + return MathArrays.verifyValues(values, weights, begin, length, false); + } + + /** + * 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 + * non-negative length and the weights array contains legitimate values.</li> + * <li>throws <code>MathIllegalArgumentException</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 unless <code>allowEmpty</code> is <code>true</code>. + * </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. + * @param allowEmpty if {@code true} than allow zero length arrays to pass. + * @return {@code true} if the parameters are valid. + * @throws NullArgumentException if either of the arrays are null + * @throws MathIllegalArgumentException if the array indices are not valid, + * the weights array contains NaN, infinite or negative elements, or there + * are no positive weights. + * @since 3.0 + */ + protected boolean test(final double[] values, final double[] weights, + final int begin, final int length, final boolean allowEmpty) throws MathIllegalArgumentException { + + return MathArrays.verifyValues(values, weights, begin, length, allowEmpty); + } +} + |