/* Copyright 2002-2017 CS Systèmes d'Information
* Licensed to CS Systèmes d'Information (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
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*/
package org.orekit.propagation.semianalytical.dsst.utilities;
import org.hipparchus.util.FastMath;
/** Interpolation grid where points obey a maximum time gap.
* <p>
* The grid is adapted to the step considered,
* meaning that for short steps, the grid will have numerous points.
* </p>
*
* @author Luc Maisonobe
* @since 7.1
*/
public class MaxGapInterpolationGrid implements InterpolationGrid {
/** Maximum time gap. */
private final double maxGap;
/** Constructor.
* @param maxGap maximum time gap between interpolation points
*/
public MaxGapInterpolationGrid(final double maxGap) {
this.maxGap = maxGap;
}
/** {@inheritDoc} */
@Override
public double[] getGridPoints(final double stepStart, final double stepEnd) {
final int pointsPerStep = FastMath.max(2, (int) FastMath.ceil(FastMath.abs(stepEnd - stepStart) / maxGap));
final double[] grid = new double[pointsPerStep];
final double stepSize = (stepEnd - stepStart) / (pointsPerStep - 1);
for (int i = 0; i < pointsPerStep; i++) {
grid[i] = stepSize * i + stepStart;
}
return grid;
}
}