| /* |
| * 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.ode; |
| |
| import java.util.Arrays; |
| import java.util.Collection; |
| import java.util.HashMap; |
| import java.util.Map; |
| |
| import org.apache.commons.math3.exception.DimensionMismatchException; |
| import org.apache.commons.math3.exception.MaxCountExceededException; |
| |
| /** Wrapper class to compute Jacobian matrices by finite differences for ODE |
| * which do not compute them by themselves. |
| * |
| * @since 3.0 |
| */ |
| class ParameterJacobianWrapper implements ParameterJacobianProvider { |
| |
| /** Main ODE set. */ |
| private final FirstOrderDifferentialEquations fode; |
| |
| /** Raw ODE without Jacobian computation skill to be wrapped into a ParameterJacobianProvider. */ |
| private final ParameterizedODE pode; |
| |
| /** Steps for finite difference computation of the Jacobian df/dp w.r.t. parameters. */ |
| private final Map<String, Double> hParam; |
| |
| /** Wrap a {@link ParameterizedODE} into a {@link ParameterJacobianProvider}. |
| * @param fode main first order differential equations set |
| * @param pode secondary problem, without parameter Jacobian computation skill |
| * @param paramsAndSteps parameters and steps to compute the Jacobians df/dp |
| * @see JacobianMatrices#setParameterStep(String, double) |
| */ |
| ParameterJacobianWrapper(final FirstOrderDifferentialEquations fode, |
| final ParameterizedODE pode, |
| final ParameterConfiguration[] paramsAndSteps) { |
| this.fode = fode; |
| this.pode = pode; |
| this.hParam = new HashMap<String, Double>(); |
| |
| // set up parameters for jacobian computation |
| for (final ParameterConfiguration param : paramsAndSteps) { |
| final String name = param.getParameterName(); |
| if (pode.isSupported(name)) { |
| hParam.put(name, param.getHP()); |
| } |
| } |
| } |
| |
| /** {@inheritDoc} */ |
| public Collection<String> getParametersNames() { |
| return pode.getParametersNames(); |
| } |
| |
| /** {@inheritDoc} */ |
| public boolean isSupported(String name) { |
| return pode.isSupported(name); |
| } |
| |
| /** {@inheritDoc} */ |
| public void computeParameterJacobian(double t, double[] y, double[] yDot, |
| String paramName, double[] dFdP) |
| throws DimensionMismatchException, MaxCountExceededException { |
| |
| final int n = fode.getDimension(); |
| if (pode.isSupported(paramName)) { |
| final double[] tmpDot = new double[n]; |
| |
| // compute the jacobian df/dp w.r.t. parameter |
| final double p = pode.getParameter(paramName); |
| final double hP = hParam.get(paramName); |
| pode.setParameter(paramName, p + hP); |
| fode.computeDerivatives(t, y, tmpDot); |
| for (int i = 0; i < n; ++i) { |
| dFdP[i] = (tmpDot[i] - yDot[i]) / hP; |
| } |
| pode.setParameter(paramName, p); |
| } else { |
| Arrays.fill(dFdP, 0, n, 0.0); |
| } |
| |
| } |
| |
| } |