TLEBatchLSModel.java

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package org.orekit.estimation.leastsquares;

import java.util.List;

import org.orekit.estimation.measurements.ObservedMeasurement;
import org.orekit.orbits.Orbit;
import org.orekit.propagation.Propagator;
import org.orekit.propagation.SpacecraftState;
import org.orekit.propagation.analytical.tle.TLEJacobiansMapper;
import org.orekit.propagation.analytical.tle.TLEPartialDerivativesEquations;
import org.orekit.propagation.analytical.tle.TLEPropagator;
import org.orekit.propagation.conversion.OrbitDeterminationPropagatorBuilder;
import org.orekit.propagation.integration.AbstractJacobiansMapper;
import org.orekit.utils.ParameterDriversList;

/** Bridge between {@link ObservedMeasurement measurements} and {@link
 * org.hipparchus.optim.nonlinear.vector.leastsquares.LeastSquaresProblem
 * least squares problems}.
 * <p>
 * This class is an adaption of the {@link BatchLSModel} class
 * but for the {@link TLEPropagator TLE propagator}.
 * </p>
 * @author Luc Maisonobe
 * @author Bryan Cazabonne
 * @author Thomas Paulet
 * @since 11.0
 *
 */
public class TLEBatchLSModel extends AbstractBatchLSModel {

    /** Simple constructor.
     * @param propagatorBuilders builders to use for propagation
     * @param measurements measurements
     * @param estimatedMeasurementsParameters estimated measurements parameters
     * @param observer observer to be notified at model calls
     */
    public TLEBatchLSModel(final OrbitDeterminationPropagatorBuilder[] propagatorBuilders,
                           final List<ObservedMeasurement<?>> measurements,
                           final ParameterDriversList estimatedMeasurementsParameters,
                           final ModelObserver observer) {
        // call super constructor
        super(propagatorBuilders, measurements, estimatedMeasurementsParameters,
              new TLEJacobiansMapper[propagatorBuilders.length], observer);
    }

    /** {@inheritDoc} */
    @Override
    protected TLEJacobiansMapper configureDerivatives(final Propagator propagator) {

        final String equationName = TLEBatchLSModel.class.getName() + "-derivatives";

        final TLEPartialDerivativesEquations partials = new TLEPartialDerivativesEquations(equationName, (TLEPropagator) propagator);

        // add the derivatives to the initial state
        final SpacecraftState rawState = propagator.getInitialState();
        final SpacecraftState stateWithDerivatives = partials.setInitialJacobians(rawState);
        propagator.resetInitialState(stateWithDerivatives);

        return partials.getMapper();

    }

    /** {@inheritDoc} */
    @Override
    protected Orbit configureOrbits(final AbstractJacobiansMapper mapper,
                                    final Propagator propagator) {
        // Directly return the propagator's initial state
        return propagator.getInitialState().getOrbit();
    }

}