1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
|
/*
* 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 org.apache.commons.math3.exception.DimensionMismatchException;
import java.io.Serializable;
/**
* 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.
*
* @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);
}
}
|
