BrouwerLyddaneGradientConverter.java
- /* Copyright 2002-2022 CS GROUP
- * Licensed to CS GROUP (CS) under one or more
- * contributor license agreements. See the NOTICE file distributed with
- * this work for additional information regarding copyright ownership.
- * CS licenses this file to You under the Apache License, Version 2.0
- * (the "License"); you may not use this file except in compliance with
- * the License. You may obtain a copy of the License at
- *
- * http://www.apache.org/licenses/LICENSE-2.0
- *
- * Unless required by applicable law or agreed to in writing, software
- * distributed under the License is distributed on an "AS IS" BASIS,
- * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
- * See the License for the specific language governing permissions and
- * limitations under the License.
- */
- package org.orekit.propagation.analytical;
- import java.util.List;
- import org.hipparchus.analysis.differentiation.Gradient;
- import org.orekit.attitudes.AttitudeProvider;
- import org.orekit.propagation.FieldSpacecraftState;
- import org.orekit.utils.ParameterDriver;
- /**
- * Converter for Brouwer-Lyddane propagator.
- *
- * @author Bryan Cazabonne
- * @since 11.1
- */
- class BrouwerLyddaneGradientConverter extends AbstractAnalyticalGradientConverter {
- /** Fixed dimension of the state. */
- public static final int FREE_STATE_PARAMETERS = 6;
- /** Orbit propagator. */
- private final BrouwerLyddanePropagator propagator;
- /** Simple constructor.
- * @param propagator orbit propagator used to access initial orbit
- */
- BrouwerLyddaneGradientConverter(final BrouwerLyddanePropagator propagator) {
- super(propagator, propagator.getMu(), FREE_STATE_PARAMETERS);
- // Initialize fields
- this.propagator = propagator;
- }
- /** {@inheritDoc} */
- @Override
- public FieldBrouwerLyddanePropagator<Gradient> getPropagator(final FieldSpacecraftState<Gradient> state,
- final Gradient[] parameters) {
- // Zero
- final Gradient zero = state.getA().getField().getZero();
- // Model parameters
- final double[] ck0 = propagator.getCk0();
- final double radius = propagator.getReferenceRadius();
- final AttitudeProvider provider = propagator.getAttitudeProvider();
- // Central attraction coefficient
- final Gradient mu = zero.add(propagator.getMu());
- // Return the "Field" propagator
- return new FieldBrouwerLyddanePropagator<Gradient>(state.getOrbit(), provider, radius, mu,
- ck0[2], ck0[3], ck0[4], ck0[5], parameters[0].getValue());
- }
- /** {@inheritDoc} */
- @Override
- public List<ParameterDriver> getParametersDrivers() {
- return propagator.getParametersDrivers();
- }
- }