1   /* Copyright 2002-2021 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.models.earth.troposphere;
18  
19  import org.hipparchus.CalculusFieldElement;
20  import org.orekit.bodies.FieldGeodeticPoint;
21  import org.orekit.bodies.GeodeticPoint;
22  import org.orekit.time.AbsoluteDate;
23  import org.orekit.time.FieldAbsoluteDate;
24  
25  /** Interface for mapping functions used in the tropospheric delay computation.
26   * @author Bryan Cazabonne
27   */
28  public interface MappingFunction {
29  
30      /** This method allows the computation of the hydrostatic and
31       * wet mapping functions. The resulting element is an array having the following form:
32       * <ul>
33       * <li>double[0] = m<sub>h</sub>(e) → hydrostatic mapping function
34       * <li>double[1] = m<sub>w</sub>(e) → wet mapping function
35       * </ul>
36       * @param elevation the elevation of the satellite, in radians
37       * @param point station location
38       * @param date current date
39       * @return a two components array containing the hydrostatic and wet mapping functions.
40       */
41      double[] mappingFactors(double elevation, GeodeticPoint point, AbsoluteDate date);
42  
43      /** This method allows the computation of the hydrostatic and
44       * wet mapping functions. The resulting element is an array having the following form:
45       * <ul>
46       * <li>T[0] = m<sub>h</sub>(e) → hydrostatic mapping function
47       * <li>T[1] = m<sub>w</sub>(e) → wet mapping function
48       * </ul>
49       * @param elevation the elevation of the satellite, in radians
50       * @param point station location
51       * @param date current date
52       * @param <T> type of the elements
53       * @return a two components array containing the hydrostatic and wet mapping functions.
54       */
55      <T extends CalculusFieldElement<T>> T[] mappingFactors(T elevation, FieldGeodeticPoint<T> point, FieldAbsoluteDate<T> date);
56  
57  }