1 /*
2 * Licensed to the Apache Software Foundation (ASF) under one or more
3 * contributor license agreements. See the NOTICE file distributed with
4 * this work for additional information regarding copyright ownership.
5 * The ASF licenses this file to You under the Apache License, Version 2.0
6 * (the "License"); you may not use this file except in compliance with
7 * the License. You may obtain a copy of the License at
8 *
9 * https://www.apache.org/licenses/LICENSE-2.0
10 *
11 * Unless required by applicable law or agreed to in writing, software
12 * distributed under the License is distributed on an "AS IS" BASIS,
13 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
14 * See the License for the specific language governing permissions and
15 * limitations under the License.
16 */
17
18 /*
19 * This is not the original file distributed by the Apache Software Foundation
20 * It has been modified by the Hipparchus project
21 */
22
23 package org.hipparchus.ode;
24
25 import org.hipparchus.ode.events.ODEEventDetector;
26
27 /**
28 * This class is used as the base class of the problems that are
29 * integrated during the junit tests for the ODE integrators.
30 */
31 public abstract class TestProblemAbstract
32 implements OrdinaryDifferentialEquation {
33
34 /** Number of functions calls. */
35 private int calls;
36
37 /** Initial state */
38 private final ODEState s0;
39
40 /** Final time */
41 private final double t1;
42
43 /** Error scale */
44 private final double[] errorScale;
45
46 /**
47 * Simple constructor.
48 * @param t0 initial time
49 * @param y0 initial state vector
50 * @param t1 final time
51 * @param errorScale error scale
52 */
53 protected TestProblemAbstract(double t0, double[] y0, double t1, double[] errorScale) {
54 calls = 0;
55 s0 = new ODEState(t0, y0);
56 this.t1 = t1;
57 this.errorScale = errorScale.clone();
58 }
59
60 public int getDimension() {
61 return s0.getPrimaryState().length;
62 }
63
64 /**
65 * Get the initial time.
66 * @return initial time
67 */
68 public double getInitialTime() {
69 return s0.getTime();
70 }
71
72 /**
73 * Get the initial state vector.
74 * @return initial state vector
75 */
76 public ODEState getInitialState() {
77 return s0;
78 }
79
80 /**
81 * Get the final time.
82 * @return final time
83 */
84 public double getFinalTime() {
85 return t1;
86 }
87
88 /**
89 * Get the error scale.
90 * @return error scale
91 */
92 public double[] getErrorScale() {
93 return errorScale;
94 }
95
96 /**
97 * Get the event detectors.
98 * @param maxCheck maximum checking interval, must be strictly positive (s)
99 * @param threshold convergence threshold (s)
100 * @param maxIter maximum number of iterations in the event time search
101 * @return events detectors */
102 public ODEEventDetector[] getEventDetectors(final double maxCheck, final double threshold, final int maxIter) {
103 return new ODEEventDetector[0];
104 }
105
106 /**
107 * Get the theoretical events times.
108 * @return theoretical events times
109 */
110 public double[] getTheoreticalEventsTimes() {
111 return new double[0];
112 }
113
114 /**
115 * Get the number of calls.
116 * @return nuber of calls
117 */
118 public int getCalls() {
119 return calls;
120 }
121
122 public double[] computeDerivatives(double t, double[] y) {
123 ++calls;
124 return doComputeDerivatives(t, y);
125 }
126
127 abstract public double[] doComputeDerivatives(double t, double[] y);
128
129 /**
130 * Compute the theoretical state at the specified time.
131 * @param t time at which the state is required
132 * @return state vector at time t
133 */
134 abstract public double[] computeTheoreticalState(double t);
135
136 }