/*-
* Copyright (c) 2013 Diamond Light Source Ltd.
*
* All rights reserved. This program and the accompanying materials
* are made available under the terms of the Eclipse Public License v1.0
* which accompanies this distribution, and is available at
* http://www.eclipse.org/legal/epl-v10.html
*/
package uk.ac.diamond.scisoft.analysis.fitting.functions;
import org.eclipse.january.asserts.TestUtils;
import org.eclipse.january.dataset.Dataset;
import org.eclipse.january.dataset.DatasetFactory;
import org.junit.Assert;
import org.junit.Test;
public class PearsonVIITest {
private static final double ABS_TOL = 1e-7;
private static final double REL_TOL = 1e-15;
@Test
public void testFunction() {
APeak f = new PearsonVII();
Assert.assertEquals(4, f.getNoOfParameters());
f.setParameterValues(23., 2., 1.2, 2);
Assert.assertArrayEquals(new double[] {23., 2., 1.2, 2}, f.getParameterValues(), ABS_TOL);
double h = 1.2 * Math.sqrt(Math.sqrt(2) - 1) / (Math.PI / 2);
Assert.assertEquals(h, f.val(23.), ABS_TOL);
Assert.assertEquals(h, f.getHeight(), ABS_TOL);
Assert.assertEquals(0.5 * h, f.val(23. - 1), ABS_TOL);
Assert.assertEquals(0.5 * h, f.val(23. + 1), ABS_TOL);
Dataset x = DatasetFactory.createLinearSpace(-50+23, 50+23, 200, Dataset.FLOAT64);
Dataset v = f.calculateValues(x);
Assert.assertEquals(1.2, ((Number) v.sum()).doubleValue() * Math.abs(x.getDouble(0) - x.getDouble(1)), 1e-4);
}
@Test
public void testExtremes() {
Dataset x = DatasetFactory.createLinearSpace(-20+23, 20+23, 401, Dataset.FLOAT64);
PearsonVII pv = new PearsonVII();
pv.getParameter(3).setUpperLimit(Double.MAX_VALUE);
pv.setParameterValues(23., 2., 1.2, 1);
Dataset pl = pv.calculateValues(x);
double power = 500000;
pv.setParameterValues(23., 2., 1.2, power);
Dataset pg = pv.calculateValues(x);
Lorentzian lf = new Lorentzian();
lf.setParameterValues(23., 2., 1.2);
Dataset l = lf.calculateValues(x);
TestUtils.assertDatasetEquals(l, pl, REL_TOL, ABS_TOL);
Gaussian gf = new Gaussian();
double width = pv.getFWHM()*Math.sqrt(2 * Math.log(2.)/( (2*power - 3) * (Math.pow(2, 1/power) - 1)));
gf.setParameterValues(23., width, 1.2);
Dataset g = gf.calculateValues(x);
TestUtils.assertDatasetEquals(g, pg, REL_TOL, 5*ABS_TOL);
}
}