KalmanObserver.java

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 * (the "License"); you may not use this file except in compliance with
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 *
 *   http://www.apache.org/licenses/LICENSE-2.0
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package org.orekit.estimation.sequential;

/** Observer for {@link KalmanEstimator Kalman filter} estimations.
 * <p>
 * This interface is intended to be implemented by users to monitor
 * the progress of the Kalman filter estimator during estimation.
 * </p>
 * @author Luc Maisonobe
 * @author Maxime Journot
 * @since 9.2
 */
@FunctionalInterface
public interface KalmanObserver {

    /** Initialise the observer on the initial state of the filter, before processing the first measurement.
     * @param estimation estimation performed by Kalman estimator
     */
    default void init(final KalmanEstimation estimation) {
    }

    /** Notification callback after each one of a Kalman filter estimation.
     * @param estimation estimation performed by Kalman estimator
     */
    void evaluationPerformed(KalmanEstimation estimation);

}