/*-
* 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.dataset.Dataset;
import org.eclipse.january.dataset.DatasetFactory;
import org.eclipse.january.dataset.DoubleDataset;
import org.junit.Assert;
import org.junit.Test;
public class FermiTest {
private static final double ABS_TOL = 1e-7;
@Test
public void testFunction() {
AFunction f = new Fermi();
Assert.assertEquals(4, f.getNoOfParameters());
f.setParameterValues(23., 110., 1.2, -5.2);
Assert.assertArrayEquals(new double[] {23., 110., 1.2, -5.2}, f.getParameterValues(), ABS_TOL);
Assert.assertEquals(1.2 / 2. - 5.2, f.val(23.), ABS_TOL);
double w = 110 * Math.log(2);
Assert.assertEquals(1.2 / 3 - 5.2, f.val(23. + w), ABS_TOL);
Assert.assertEquals(1.2 / 1.5 - 5.2, f.val(23. - w), ABS_TOL);
Dataset xd = DatasetFactory.createFromObject(new double[] {23. - w, 23, 23. + 2 * w});
DoubleDataset dx;
dx = f.calculateValues(xd);
Assert.assertArrayEquals(new double[] {1.2/1.5 - 5.2, 1.2/2 - 5.2, 1.2/5 - 5.2}, dx.getData(), ABS_TOL);
}
}