QuadraticFieldClockModel.java
/* Copyright 2002-2024 Thales Alenia Space
* 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
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*/
package org.orekit.estimation.measurements;
import org.hipparchus.CalculusFieldElement;
import org.orekit.time.FieldAbsoluteDate;
import org.orekit.time.FieldClockOffset;
/** Quadratic clock model.
*
* @param <T> type of the field elements
* @author Luc Maisonobe
* @since 12.1
*
*/
public class QuadraticFieldClockModel<T extends CalculusFieldElement<T>> {
/** Clock model reference date. */
private final FieldAbsoluteDate<T> referenceDate;
/** Constant term. */
private final T a0;
/** Linear term. */
private final T a1;
/** Quadratic term. */
private final T a2;
/** Simple constructor.
* @param referenceDate reference date
* @param a0 constant term
* @param a1 linear term
* @param a2 quadratic term
*/
public QuadraticFieldClockModel(final FieldAbsoluteDate<T> referenceDate,
final T a0, final T a1, final T a2) {
this.referenceDate = referenceDate;
this.a0 = a0;
this.a1 = a1;
this.a2 = a2;
}
/** Get the clock offset at date.
* @param date date at which offset is requested
* @return clock offset at specified date
*/
public FieldClockOffset<T> getOffset(final FieldAbsoluteDate<T> date) {
final T dt = date.durationFrom(referenceDate);
return new FieldClockOffset<>(date,
a2.multiply(dt).add(a1).multiply(dt).add(a0),
a2.multiply(dt).multiply(2).add(a1),
a2.multiply(2));
}
}