1   /* Copyright 2002-2022 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.numerical;
18  
19  import java.util.List;
20  
21  import org.hipparchus.linear.RealMatrix;
22  import org.orekit.orbits.Orbit;
23  import org.orekit.propagation.AbstractMatricesHarvester;
24  import org.orekit.propagation.SpacecraftState;
25  import org.orekit.utils.DoubleArrayDictionary;
26  
27  /** Harvester between two-dimensional Jacobian matrices and one-dimensional {@link
28   * SpacecraftState#getAdditionalState(String) additional state arrays}.
29   * @author Luc Maisonobe
30   * @since 11.1
31   */
32  class NumericalPropagationHarvester extends AbstractMatricesHarvester {
33  
34      /** Propagator bound to this harvester. */
35      private final NumericalPropagator propagator;
36  
37      /** Columns names for parameters. */
38      private List<String> columnsNames;
39  
40      /** Simple constructor.
41       * <p>
42       * The arguments for initial matrices <em>must</em> be compatible with the {@link org.orekit.orbits.OrbitType orbit type}
43       * and {@link org.orekit.orbits.PositionAngle position angle} that will be used by propagator
44       * </p>
45       * @param propagator propagator bound to this harvester
46       * @param stmName State Transition Matrix state name
47       * @param initialStm initial State Transition Matrix ∂Y/∂Y₀,
48       * if null (which is the most frequent case), assumed to be 6x6 identity
49       * @param initialJacobianColumns initial columns of the Jacobians matrix with respect to parameters,
50       * if null or if some selected parameters are missing from the dictionary, the corresponding
51       * initial column is assumed to be 0
52       */
53      NumericalPropagationHarvester(final NumericalPropagator propagator, final String stmName,
54                                    final RealMatrix initialStm, final DoubleArrayDictionary initialJacobianColumns) {
55          super(stmName, initialStm, initialJacobianColumns);
56          this.propagator   = propagator;
57          this.columnsNames = null;
58      }
59  
60      /** {@inheritDoc} */
61      @Override
62      protected double[][] getConversionJacobian(final SpacecraftState state) {
63  
64          final double[][] dYdC = new double[STATE_DIMENSION][STATE_DIMENSION];
65  
66          if (state.isOrbitDefined()) {
67              // make sure the state is in the desired orbit type
68              final Orbit orbit = propagator.getOrbitType().convertType(state.getOrbit());
69  
70              // compute the Jacobian, taking the position angle type into account
71              orbit.getJacobianWrtCartesian(propagator.getPositionAngleType(), dYdC);
72          } else {
73              // for absolute PVA, parameters are already Cartesian
74              for (int i = 0; i < STATE_DIMENSION; ++i) {
75                  dYdC[i][i] = 1.0;
76              }
77          }
78  
79          return dYdC;
80  
81      }
82  
83      /** {@inheritDoc} */
84      @Override
85      public void freezeColumnsNames() {
86          columnsNames = getJacobiansColumnsNames();
87      }
88  
89      /** {@inheritDoc} */
90      @Override
91      public List<String> getJacobiansColumnsNames() {
92          return columnsNames == null ? propagator.getJacobiansColumnsNames() : columnsNames;
93      }
94  
95  }