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;
18  
19  
20  /** Interface for retrieving estimated measurements during orbit determination.
21   * <p>
22   * Implementations of this interface are provided by the orbit
23   * determination engine to user so they can {@link
24   * org.orekit.estimation.leastsquares.BatchLSObserver monitor}
25   * the orbit determination process.
26   * </p>
27   * @see org.orekit.estimation.leastsquares.BatchLSObserver
28   * @author Luc Maisonobe
29   * @since 8.0
30   */
31  public interface EstimationsProvider {
32  
33      /** Get the number of evaluations available.
34       * @return number of evaluations available
35       */
36      int getNumber();
37  
38      /** Get one estimated measurement.
39       * @param index index of the estimated measurement, must be between 0
40       * and {@link #getNumber() getNumber()} - 1, chronologically
41       * sorted
42       * @return estimated measurement at specified index
43       */
44      EstimatedMeasurement<?> getEstimatedMeasurement(int index);
45  
46  }