1 /* Copyright 2002-2026 CS GROUP
2 * Licensed to CS GROUP (CS) under one or more
3 * contributor license agreements. See the NOTICE file distributed with
4 * this work for additional information regarding copyright ownership.
5 * CS 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 * http://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 package org.orekit.propagation;
18
19 import org.hipparchus.linear.MatrixUtils;
20 import org.hipparchus.linear.RealMatrix;
21 import org.orekit.orbits.PositionAngleType;
22 import org.orekit.utils.DoubleArrayDictionary;
23
24 /** Base harvester between two-dimensional Jacobian matrices and one-dimensional {@link
25 * SpacecraftState#getAdditionalState(String) additional state arrays}.
26 * @author Luc Maisonobe
27 * @since 11.1
28 */
29 public abstract class AbstractMatricesHarvester implements MatricesHarvester {
30
31 /** Default state dimension, equivalent to position and velocity vectors. */
32 public static final int DEFAULT_STATE_DIMENSION = 6;
33
34 /** State Transition Matrix state name. */
35 private String stmName;
36
37 /** Initial State Transition Matrix. */
38 private RealMatrix initialStm;
39
40 /** Initial columns of the Jacobians matrix with respect to parameters. */
41 private DoubleArrayDictionary initialJacobianColumns;
42
43 /** Empty constructor.
44 * <p>
45 * This constructor is not strictly necessary, but it prevents spurious
46 * javadoc warnings with JDK 18 and later.
47 * </p>
48 * @since 14.0
49 */
50 public AbstractMatricesHarvester() {
51 // nothing to do
52 }
53
54 /** Set the initial State Transition Matrix.
55 * <p>
56 * The arguments for initial matrices <em>must</em> be compatible with the
57 * {@link org.orekit.orbits.OrbitType orbit type} and
58 * {@link PositionAngleType position angle} that will be used by propagator,
59 * which may be different from input and output
60 * </p>
61 * @param name State Transition Matrix state name
62 * @param stm initial State Transition Matrix āY/āIā
63 * if null (which is the most frequent case), input and output
64 * orbit types are assumed to be identical and the matrix is
65 * assumed to be the 6x6 identity
66 */
67 protected void setInitialStm(final String name, final RealMatrix stm) {
68 this.stmName = name;
69 this.initialStm = stm == null ?
70 MatrixUtils.createRealIdentityMatrix(DEFAULT_STATE_DIMENSION) :
71 stm;
72 }
73
74 /** Set the initial columns of the Jacobians matrix with respect to parameters.
75 * <p>
76 * The arguments for initial matrices <em>must</em> be compatible with the
77 * {@link org.orekit.orbits.OrbitType orbit type} and
78 * {@link PositionAngleType position angle} that will be used by propagator
79 * </p>
80 * @param initialJacobianColumns initial columns of the Jacobians matrix with respect to parameters,
81 * if null or if some selected parameters are missing from the dictionary, the corresponding
82 * initial column is assumed to be 0
83 */
84 protected void setInitialJacobianColumns(final DoubleArrayDictionary initialJacobianColumns) {
85 this.initialJacobianColumns = initialJacobianColumns == null ?
86 new DoubleArrayDictionary() :
87 initialJacobianColumns;
88 }
89
90 /**
91 * Getter for the state dimension.
92 * @return state dimension
93 * @since 13.1
94 */
95 public int getStateDimension() {
96 return initialStm.getColumnDimension();
97 }
98
99 /** Get the State Transition Matrix state name.
100 * @return State Transition Matrix state name
101 */
102 public String getStmName() {
103 return stmName;
104 }
105
106 /** Get the initial State Transition Matrix.
107 * @return initial State Transition Matrix
108 */
109 public RealMatrix getInitialStateTransitionMatrix() {
110 return initialStm;
111 }
112
113 /** Get the initial column of Jacobian matrix with respect to named parameter.
114 * @param columnName name of the column
115 * @return initial column of the Jacobian matrix
116 */
117 public double[] getInitialJacobianColumn(final String columnName) {
118 final DoubleArrayDictionary.Entry entry = initialJacobianColumns.getEntry(columnName);
119 return entry == null ? new double[getStateDimension()] : entry.getValue();
120 }
121
122 /** Convert a flattened array to a square matrix.
123 * @param array input array
124 * @return the corresponding matrix
125 * @since 13.1
126 */
127 public RealMatrix toSquareMatrix(final double[] array) {
128 final int stateDimension = getStateDimension();
129 final RealMatrix matrix = MatrixUtils.createRealMatrix(stateDimension, stateDimension);
130 int index = 0;
131 for (int i = 0; i < stateDimension; ++i) {
132 for (int j = 0; j < stateDimension; ++j) {
133 matrix.setEntry(i, j, array[index++]);
134 }
135 }
136 return matrix;
137 }
138
139 /** Set the STM data into an array.
140 * @param matrix STM matrix
141 * @return an array containing the STM data
142 * @since 13.1
143 */
144 public double[] toArray(final double[][] matrix) {
145 final int stateDimension = matrix.length;
146 final double[] array = new double[stateDimension * stateDimension];
147 int index = 0;
148 for (final double[] row : matrix) {
149 for (int j = 0; j < stateDimension; ++j) {
150 array[index++] = row[j];
151 }
152 }
153 return array;
154 }
155
156 /** {@inheritDoc} */
157 @Override
158 public void setReferenceState(final SpacecraftState reference) {
159 // nothing to do
160 }
161
162 /** Freeze the names of the Jacobian columns.
163 * <p>
164 * This method is called when propagation starts, i.e. when configuration is completed
165 * </p>
166 */
167 public abstract void freezeColumnsNames();
168
169 }