VectorialMean.java
- /*
- * 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.moment;
- import java.util.Arrays;
- import org.apache.commons.math4.legacy.exception.DimensionMismatchException;
- /**
- * Returns the arithmetic mean of the available vectors.
- * @since 1.2
- */
- public class VectorialMean {
- /** Means for each component. */
- private final Mean[] means;
- /** Constructs a VectorialMean.
- * @param dimension vectors dimension
- */
- public VectorialMean(int dimension) {
- means = new Mean[dimension];
- for (int i = 0; i < dimension; ++i) {
- means[i] = new Mean();
- }
- }
- /**
- * Add a new vector to the sample.
- * @param v vector to add
- * @throws DimensionMismatchException if the vector does not have the right dimension
- */
- public void increment(double[] v) throws DimensionMismatchException {
- if (v.length != means.length) {
- throw new DimensionMismatchException(v.length, means.length);
- }
- for (int i = 0; i < v.length; ++i) {
- means[i].increment(v[i]);
- }
- }
- /**
- * Get the mean vector.
- * @return mean vector
- */
- public double[] getResult() {
- double[] result = new double[means.length];
- for (int i = 0; i < result.length; ++i) {
- result[i] = means[i].getResult();
- }
- return result;
- }
- /**
- * Get the number of vectors in the sample.
- * @return number of vectors in the sample
- */
- public long getN() {
- return (means.length == 0) ? 0 : means[0].getN();
- }
- /** {@inheritDoc} */
- @Override
- public int hashCode() {
- final int prime = 31;
- int result = 1;
- result = prime * result + Arrays.hashCode(means);
- return result;
- }
- /** {@inheritDoc} */
- @Override
- public boolean equals(Object obj) {
- if (this == obj) {
- return true;
- }
- if (!(obj instanceof VectorialMean)) {
- return false;
- }
- VectorialMean other = (VectorialMean) obj;
- return Arrays.equals(means, other.means);
- }
- }