FieldCombinedDerivatives.java

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package org.orekit.propagation.integration;

import org.hipparchus.CalculusFieldElement;

/** Container for additional derivatives.
 * @see FieldAdditionalDerivativesProvider
 * @author Luc Maisonobe
 * @since 11.2
 * @param <T> type of the field elements
 */
public class FieldCombinedDerivatives<T extends CalculusFieldElement<T>> {

    /** Additional state derivatives. */
    private T[] additionalDerivatives;

    /** Primary state derivatives increments (may be null). */
    private final T[] mainStateDerivativesIncrements;

    /** Simple constructor.
     * @param additionalDerivatives additional state derivatives
     * @param mainStateDerivativesIncrements increments related to the main state parameters
     * (may be null if main state should not be incremented)
     */
    public FieldCombinedDerivatives(final T[] additionalDerivatives,
                                    final T[] mainStateDerivativesIncrements) {
        this.mainStateDerivativesIncrements = mainStateDerivativesIncrements == null ?
                                              null : mainStateDerivativesIncrements.clone();
        this.additionalDerivatives          = additionalDerivatives.clone();
    }

    /** Get the derivatives increments related to the main state.
     * @return primary state derivatives increments, or null if
     * main state should not be incremented
     */
    public T[] getMainStateDerivativesIncrements() {
        return mainStateDerivativesIncrements == null ?
               null : mainStateDerivativesIncrements.clone();
    }

    /** Get the derivatives related to the additional state.
     * @return additional state derivatives
     */
    public T[] getAdditionalDerivatives() {
        return additionalDerivatives.clone();
    }

}