1   /* Copyright 2022-2025 Romain Serra
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.propagation.conversion;
18  
19  import org.hipparchus.Field;
20  import org.hipparchus.complex.Complex;
21  import org.hipparchus.complex.ComplexField;
22  import org.hipparchus.geometry.euclidean.threed.Vector3D;
23  import org.hipparchus.ode.FieldODEIntegrator;
24  import org.hipparchus.ode.nonstiff.ClassicalRungeKuttaFieldIntegrator;
25  import org.junit.jupiter.api.Assertions;
26  import org.junit.jupiter.api.Test;
27  import org.orekit.frames.FramesFactory;
28  import org.orekit.orbits.CartesianOrbit;
29  import org.orekit.orbits.FieldCartesianOrbit;
30  import org.orekit.orbits.OrbitType;
31  import org.orekit.time.AbsoluteDate;
32  import org.orekit.utils.AbsolutePVCoordinates;
33  import org.orekit.utils.FieldAbsolutePVCoordinates;
34  
35  class AbstractFieldIntegratorBuilderTest {
36  
37      @Test
38      void testBuildIntegrator() {
39          // GIVEN
40          final AbsolutePVCoordinates absolutePVCoordinates = new AbsolutePVCoordinates(FramesFactory.getGCRF(),
41                  AbsoluteDate.ARBITRARY_EPOCH, Vector3D.MINUS_I, Vector3D.MINUS_K);
42          final double step = 10;
43          final Field<Complex> field = ComplexField.getInstance();
44          final FieldAbsolutePVCoordinates<Complex> fieldAbsolutePVCoordinates = new FieldAbsolutePVCoordinates<>(field, absolutePVCoordinates);
45          final ClassicalRungeKuttaFieldIntegratorBuilder<Complex> builder = new ClassicalRungeKuttaFieldIntegratorBuilder<>(field.getOne().newInstance(step));
46          // WHEN
47          final FieldODEIntegrator<Complex> integrator = builder.buildIntegrator(fieldAbsolutePVCoordinates);
48          // THEN
49          final ClassicalRungeKuttaFieldIntegrator<Complex> actualIntegrator = (ClassicalRungeKuttaFieldIntegrator<Complex>) integrator;
50          final CartesianOrbit orbit = new CartesianOrbit(absolutePVCoordinates.getPVCoordinates(), absolutePVCoordinates.getFrame(),
51                  absolutePVCoordinates.getDate(), 1.);
52          final FieldCartesianOrbit<Complex> fieldOrbit = new FieldCartesianOrbit<>(field, orbit);
53          final ClassicalRungeKuttaFieldIntegrator<Complex> expectedIntegrator = (ClassicalRungeKuttaFieldIntegrator<Complex>) builder.buildIntegrator(fieldOrbit, OrbitType.CARTESIAN);
54          Assertions.assertEquals(expectedIntegrator.getCurrentSignedStepsize(), actualIntegrator.getCurrentSignedStepsize());
55      }
56  
57  }