1   /* Copyright 2002-2025 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
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16   */
17  package org.orekit.propagation.semianalytical.dsst.forces;
18  
19  import java.util.Map;
20  import java.util.Set;
21  
22  import org.hipparchus.CalculusFieldElement;
23  import org.orekit.orbits.FieldOrbit;
24  import org.orekit.time.FieldAbsoluteDate;
25  
26  /** Additive short period terms contributing to the mean to osculating orbit mapping.
27   * <p>
28   * Each instance contains a set of several terms that are computed together.
29   * </p>
30   * @see DSSTForceModel
31   * @author Luc Maisonobe
32   * @param <T> type of the field elements
33   */
34  public interface FieldShortPeriodTerms <T extends CalculusFieldElement<T>> {
35  
36      /** Evaluate the contributions of the short period terms.
37       * @param meanOrbit mean orbit to which the short period contribution applies
38       * @return short period terms contributions
39       */
40      T[] value(FieldOrbit<T> meanOrbit);
41  
42      /** Get the prefix for short period coefficients keys.
43       * <p>
44       * This prefix is used to identify the coefficients of the
45       * current force model from the coefficients pertaining to
46       * other force models. All the keys in the map returned by
47       * {@link #getCoefficients(FieldAbsoluteDate, Set)}
48       * start with this prefix, which must be unique among all
49       * providers.
50       * </p>
51       * @return the prefix for short periodic coefficients keys
52       * @see #getCoefficients(FieldAbsoluteDate, Set)
53       */
54      String getCoefficientsKeyPrefix();
55  
56      /** Computes the coefficients involved in the contributions.
57       * <p>
58       * This method is intended mainly for validation purposes. Its output
59       * is highly dependent on the implementation details in each force model
60       * and may change from version to version. It is <em>not</em> recommended
61       * to use it for any operational purposes.
62       * </p>
63       * @param date current date
64       * @param selected set of coefficients that should be put in the map
65       * (empty set means all coefficients are selected)
66       * @return the selected coefficients of the short periodic variations,
67       * in a map where all keys start with {@link #getCoefficientsKeyPrefix()}
68       */
69      Map<String, T[]> getCoefficients(FieldAbsoluteDate<T> date, Set<String> selected);
70  
71  }