| /* |
| * 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.ode; |
| |
| import java.io.Serializable; |
| |
| import org.apache.commons.math4.legacy.exception.DimensionMismatchException; |
| |
| /** |
| * Class mapping the part of a complete state or derivative that pertains |
| * to a specific differential equation. |
| * <p> |
| * Instances of this class are guaranteed to be immutable. |
| * </p> |
| * @see SecondaryEquations |
| * @since 3.0 |
| */ |
| public class EquationsMapper implements Serializable { |
| |
| /** Serializable UID. */ |
| private static final long serialVersionUID = 20110925L; |
| |
| /** Index of the first equation element in complete state arrays. */ |
| private final int firstIndex; |
| |
| /** Dimension of the secondary state parameters. */ |
| private final int dimension; |
| |
| /** simple constructor. |
| * @param firstIndex index of the first equation element in complete state arrays |
| * @param dimension dimension of the secondary state parameters |
| */ |
| public EquationsMapper(final int firstIndex, final int dimension) { |
| this.firstIndex = firstIndex; |
| this.dimension = dimension; |
| } |
| |
| /** Get the index of the first equation element in complete state arrays. |
| * @return index of the first equation element in complete state arrays |
| */ |
| public int getFirstIndex() { |
| return firstIndex; |
| } |
| |
| /** Get the dimension of the secondary state parameters. |
| * @return dimension of the secondary state parameters |
| */ |
| public int getDimension() { |
| return dimension; |
| } |
| |
| /** Extract equation data from a complete state or derivative array. |
| * @param complete complete state or derivative array from which |
| * equation data should be retrieved |
| * @param equationData placeholder where to put equation data |
| * @throws DimensionMismatchException if the dimension of the equation data does not |
| * match the mapper dimension |
| */ |
| public void extractEquationData(double[] complete, double[] equationData) |
| throws DimensionMismatchException { |
| if (equationData.length != dimension) { |
| throw new DimensionMismatchException(equationData.length, dimension); |
| } |
| System.arraycopy(complete, firstIndex, equationData, 0, dimension); |
| } |
| |
| /** Insert equation data into a complete state or derivative array. |
| * @param equationData equation data to be inserted into the complete array |
| * @param complete placeholder where to put equation data (only the |
| * part corresponding to the equation will be overwritten) |
| * @throws DimensionMismatchException if the dimension of the equation data does not |
| * match the mapper dimension |
| */ |
| public void insertEquationData(double[] equationData, double[] complete) |
| throws DimensionMismatchException { |
| if (equationData.length != dimension) { |
| throw new DimensionMismatchException(equationData.length, dimension); |
| } |
| System.arraycopy(equationData, 0, complete, firstIndex, dimension); |
| } |
| |
| } |