

Java example source code file (JacobianFunction.java)
The JacobianFunction.java Java example source code/* * 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/LICENSE2.0 * * 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.analysis.differentiation; import org.apache.commons.math3.analysis.MultivariateMatrixFunction; /** Class representing the Jacobian of a multivariate vector function. * <p> * The rows iterate on the model functions while the columns iterate on the parameters; thus, * the numbers of rows is equal to the dimension of the underlying function vector * value and the number of columns is equal to the number of free parameters of * the underlying function. * </p> * @since 3.1 */ public class JacobianFunction implements MultivariateMatrixFunction { /** Underlying vectorvalued function. */ private final MultivariateDifferentiableVectorFunction f; /** Simple constructor. * @param f underlying vectorvalued function */ public JacobianFunction(final MultivariateDifferentiableVectorFunction f) { this.f = f; } /** {@inheritDoc} */ public double[][] value(double[] point) { // set up parameters final DerivativeStructure[] dsX = new DerivativeStructure[point.length]; for (int i = 0; i < point.length; ++i) { dsX[i] = new DerivativeStructure(point.length, 1, i, point[i]); } // compute the derivatives final DerivativeStructure[] dsY = f.value(dsX); // extract the Jacobian final double[][] y = new double[dsY.length][point.length]; final int[] orders = new int[point.length]; for (int i = 0; i < dsY.length; ++i) { for (int j = 0; j < point.length; ++j) { orders[j] = 1; y[i][j] = dsY[i].getPartialDerivative(orders); orders[j] = 0; } } return y; } } Other Java examples (source code examples)Here is a short list of links related to this Java JacobianFunction.java source code file: 
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