1   /* Copyright 2002-2025 CS GROUP
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3    * contributor license agreements.  See the NOTICE file distributed with
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9    *   http://www.apache.org/licenses/LICENSE-2.0
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11   * Unless required by applicable law or agreed to in writing, software
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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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17  package org.orekit.propagation.semianalytical.dsst.utilities;
18  
19  import org.hipparchus.CalculusFieldElement;
20  
21  /**  Interface for interpolation grids.
22   * <p>
23   * An interpolation grid provides a grid of time points
24   * that can be used for interpolation processes.
25   * </p>
26   * <p>
27   * In the context of DSST propagation, an interpolation grid is used for the
28   * computation through interpolation of short periodics coefficients
29   * </p>
30   * @author Nicolas Bernard
31   * @param <T> type of the field elements
32   */
33  public interface FieldInterpolationGrid<T extends CalculusFieldElement<T>> {
34  
35      /** Get grid points that are within the current step.
36       * <p>The step is defined by its start and its end time.
37       * </p>
38       * @param stepStart start of the step
39       * @param stepEnd end of the step
40       * @return time points between start and end
41       */
42      T[] getGridPoints(T stepStart, T stepEnd);
43  }