01: /*
02: * Copyright 2004 The Apache Software Foundation
03: *
04: * Licensed under the Apache License, Version 2.0 (the "License");
05: * you may not use this file except in compliance with the License.
06: * You may obtain a copy of the License at
07: *
08: * http://www.apache.org/licenses/LICENSE-2.0
09: *
10: * Unless required by applicable law or agreed to in writing, software
11: * distributed under the License is distributed on an "AS IS" BASIS,
12: * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
13: * See the License for the specific language governing permissions and
14: * limitations under the License.
15: */
16:
17: package org.apache.commons.math.special;
18:
19: import org.apache.commons.math.MathException;
20:
21: import junit.framework.TestCase;
22:
23: /**
24: * @version $Revision: 155427 $ $Date: 2005-02-26 06:11:52 -0700 (Sat, 26 Feb 2005) $
25: */
26: public class ErfTest extends TestCase {
27:
28: public void testErf0() throws MathException {
29: double actual = Erf.erf(0.0);
30: double expected = 0.0;
31: assertEquals(expected, actual, 1.0e-5);
32: }
33:
34: public void testErf1960() throws MathException {
35: double x = 1.960 / Math.sqrt(2.0);
36: double actual = Erf.erf(x);
37: double expected = 0.95;
38: assertEquals(expected, actual, 1.0e-5);
39:
40: actual = Erf.erf(-x);
41: expected = -expected;
42: assertEquals(expected, actual, 1.0e-5);
43: }
44:
45: public void testErf2576() throws MathException {
46: double x = 2.576 / Math.sqrt(2.0);
47: double actual = Erf.erf(x);
48: double expected = 0.99;
49: assertEquals(expected, actual, 1.0e-5);
50:
51: actual = Erf.erf(-x);
52: expected = -expected;
53: assertEquals(expected, actual, 1.0e-5);
54: }
55:
56: public void testErf2807() throws MathException {
57: double x = 2.807 / Math.sqrt(2.0);
58: double actual = Erf.erf(x);
59: double expected = 0.995;
60: assertEquals(expected, actual, 1.0e-5);
61:
62: actual = Erf.erf(-x);
63: expected = -expected;
64: assertEquals(expected, actual, 1.0e-5);
65: }
66:
67: public void testErf3291() throws MathException {
68: double x = 3.291 / Math.sqrt(2.0);
69: double actual = Erf.erf(x);
70: double expected = 0.999;
71: assertEquals(expected, actual, 1.0e-5);
72:
73: actual = Erf.erf(-x);
74: expected = -expected;
75: assertEquals(expected, actual, 1.0e-5);
76: }
77: }
|