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 * 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
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 * Unless required by applicable law or agreed to in writing, software
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package org.apache.commons.math3.ode;

import java.io.Serializable;

import org.apache.commons.math3.exception.DimensionMismatchException;

Class mapping the part of a complete state or derivative that pertains
to a specific differential equation.

Instances of this class are guaranteed to be immutable.

See Also:
SecondaryEquations
Since:
3.0/**
 * 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. /** Serializable UID. */
    private static final long serialVersionUID = 20110925L;

    
Index of the first equation element in complete state arrays. /** Index of the first equation element in complete state arrays. */
    private final int firstIndex;

    
Dimension of the secondary state parameters. /** Dimension of the secondary state parameters. */
    private final int dimension;

    
simple constructor.
Params:
firstIndex – index of the first equation element in complete state arrays
dimension – dimension of the secondary state parameters/** 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.
Returns:
index of the first equation element in complete state arrays/** 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.
Returns:
dimension of the secondary state parameters/** 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.
Params:
complete – complete state or derivative array from which
equation data should be retrieved
equationData – placeholder where to put equation data
Throws:
DimensionMismatchException – if the dimension of the equation data does not
match the mapper 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.
Params:
equationData – equation data to be inserted into the complete array
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/** 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);
    }

}