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
15   * limitations under the License.
16   */
17  package org.orekit.estimation.measurements.generation;
18  
19  /** Enumerate for the semantic of the {@code g} function sign during measurements generation.
20   * @see EventBasedScheduler
21   * @author Luc Maisonobe
22   * @since 9.3
23   */
24  public enum SignSemantic {
25  
26      /** Semantic for detectors that have positive g function when measurements are feasible. */
27      FEASIBLE_MEASUREMENT_WHEN_POSITIVE(+1.0),
28  
29      /** Semantic for detectors that have negative g function when measurements are feasible. */
30      FEASIBLE_MEASUREMENT_WHEN_NEGATIVE(-1.0);
31  
32      /** Reference sign. */
33      private final double sign;
34  
35      /** Simple constructor.
36       * @param sign reference sign
37       */
38      SignSemantic(final double sign) {
39          this.sign = sign;
40      }
41  
42      /** Check if measurement is feasible.
43       * @param g value of the detector g function
44       * @return true if measurement is feasible
45       */
46      public boolean measurementIsFeasible(final double g) {
47          return sign * g >= 0;
48      }
49  
50  }