/*
* Licensed to the Apache Software Foundation (ASF) under one or more
* contributor license agreements. See the NOTICE file distributed with
* this work for additional information regarding copyright ownership.
* The ASF 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.apache.commons.math3.optim.nonlinear.vector.jacobian;
import org.apache.commons.math3.random.RandomGenerator;
import org.apache.commons.math3.random.Well44497b;
import org.apache.commons.math3.util.MathUtils;
import org.apache.commons.math3.util.FastMath;
import org.apache.commons.math3.distribution.RealDistribution;
import org.apache.commons.math3.distribution.UniformRealDistribution;
import org.apache.commons.math3.distribution.NormalDistribution;
import org.apache.commons.math3.geometry.euclidean.twod.Vector2D;
/**
* Factory for generating a cloud of points that approximate a circle.
*/
@Deprecated
public class RandomCirclePointGenerator {
/** RNG for the x-coordinate of the center. */
private final RealDistribution cX;
/** RNG for the y-coordinate of the center. */
private final RealDistribution cY;
/** RNG for the parametric position of the point. */
private final RealDistribution tP;
/** Radius of the circle. */
private final double radius;
/**
* @param x Abscissa of the circle center.
* @param y Ordinate of the circle center.
* @param radius Radius of the circle.
* @param xSigma Error on the x-coordinate of the circumference points.
* @param ySigma Error on the y-coordinate of the circumference points.
* @param seed RNG seed.
*/
public RandomCirclePointGenerator(double x,
double y,
double radius,
double xSigma,
double ySigma,
long seed) {
final RandomGenerator rng = new Well44497b(seed);
this.radius = radius;
cX = new NormalDistribution(rng, x, xSigma,
NormalDistribution.DEFAULT_INVERSE_ABSOLUTE_ACCURACY);
cY = new NormalDistribution(rng, y, ySigma,
NormalDistribution.DEFAULT_INVERSE_ABSOLUTE_ACCURACY);
tP = new UniformRealDistribution(rng, 0, MathUtils.TWO_PI,
UniformRealDistribution.DEFAULT_INVERSE_ABSOLUTE_ACCURACY);
}
/**
* Point generator.
*
* @param n Number of points to create.
* @return the cloud of {@code n} points.
*/
public Vector2D[] generate(int n) {
final Vector2D[] cloud = new Vector2D[n];
for (int i = 0; i < n; i++) {
cloud[i] = create();
}
return cloud;
}
/**
* Create one point.
*
* @return a point.
*/
private Vector2D create() {
final double t = tP.sample();
final double pX = cX.sample() + radius * FastMath.cos(t);
final double pY = cY.sample() + radius * FastMath.sin(t);
return new Vector2D(pX, pY);
}
}