BatchLSModel.java

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package org.orekit.estimation.leastsquares;

import java.util.List;

import org.hipparchus.linear.MatrixUtils;
import org.hipparchus.linear.RealMatrix;
import org.orekit.estimation.measurements.ObservedMeasurement;
import org.orekit.orbits.Orbit;
import org.orekit.propagation.MatricesHarvester;
import org.orekit.propagation.Propagator;
import org.orekit.propagation.conversion.PropagatorBuilder;
import org.orekit.propagation.numerical.NumericalPropagator;
import org.orekit.utils.ParameterDriversList;

/** Bridge between {@link ObservedMeasurement measurements} and {@link
 * org.hipparchus.optim.nonlinear.vector.leastsquares.LeastSquaresProblem
 * least squares problems}.
 * @author Luc Maisonobe
 * @since 8.0
 */
public class BatchLSModel extends AbstractBatchLSModel {

    /** Name of the State Transition Matrix state. */
    private static final String STM_NAME = BatchLSModel.class.getName() + "-derivatives";

    /** 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 BatchLSModel(final PropagatorBuilder[] propagatorBuilders,
                        final List<ObservedMeasurement<?>> measurements,
                        final ParameterDriversList estimatedMeasurementsParameters,
                        final ModelObserver observer) {
        // call super constructor
        super(propagatorBuilders, measurements, estimatedMeasurementsParameters, observer);
    }

    /** {@inheritDoc} */
    @Override
    protected MatricesHarvester configureHarvester(final Propagator propagator) {
        final RealMatrix initialStm;
        if (propagator instanceof NumericalPropagator) {
            initialStm = MatrixUtils.createRealIdentityMatrix(7);
        } else {
            initialStm = MatrixUtils.createRealIdentityMatrix(6);
        }
        return propagator.setupMatricesComputation(STM_NAME, initialStm, null);
    }

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

}