/*
* 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.math.random;
import org.apache.commons.math.stat.Frequency;
/**
* Test cases for the AbstractRandomGenerator class
*
* @version $Revision: 902201 $ $Date: 2010-01-22 13:18:16 -0500 (Fri, 22 Jan 2010) $
*/
public class AbstractRandomGeneratorTest extends RandomDataTest {
protected TestRandomGenerator testGenerator = new TestRandomGenerator();
public AbstractRandomGeneratorTest(String name) {
super(name);
randomData = new RandomDataImpl(testGenerator);
}
@Override
public void testNextInt() {
try {
testGenerator.nextInt(-1);
fail("IllegalArgumentException expected");
} catch (IllegalArgumentException ex) {
// ignored
}
Frequency freq = new Frequency();
int value = 0;
for (int i=0; i<smallSampleSize; i++) {
value = testGenerator.nextInt(4);
assertTrue("nextInt range",(value >= 0) && (value <= 3));
freq.addValue(value);
}
long[] observed = new long[4];
for (int i=0; i<4; i++) {
observed[i] = freq.getCount(i);
}
/* Use ChiSquare dist with df = 4-1 = 3, alpha = .001
* Change to 11.34 for alpha = .01
*/
assertTrue("chi-square test -- will fail about 1 in 1000 times",
testStatistic.chiSquare(expected,observed) < 16.27);
}
@Override
public void testNextLong() {
long q1 = Long.MAX_VALUE/4;
long q2 = 2 * q1;
long q3 = 3 * q1;
Frequency freq = new Frequency();
long val = 0;
int value = 0;
for (int i=0; i<smallSampleSize; i++) {
val = testGenerator.nextLong();
if (val < q1) {
value = 0;
} else if (val < q2) {
value = 1;
} else if (val < q3) {
value = 2;
} else {
value = 3;
}
freq.addValue(value);
}
long[] observed = new long[4];
for (int i=0; i<4; i++) {
observed[i] = freq.getCount(i);
}
/* Use ChiSquare dist with df = 4-1 = 3, alpha = .001
* Change to 11.34 for alpha = .01
*/
assertTrue("chi-square test -- will fail about 1 in 1000 times",
testStatistic.chiSquare(expected,observed) < 16.27);
}
public void testNextBoolean() {
long halfSampleSize = smallSampleSize / 2;
double[] expected = {halfSampleSize, halfSampleSize};
long[] observed = new long[2];
for (int i=0; i<smallSampleSize; i++) {
if (testGenerator.nextBoolean()) {
observed[0]++;
} else {
observed[1]++;
}
}
/* Use ChiSquare dist with df = 2-1 = 1, alpha = .001
* Change to 6.635 for alpha = .01
*/
assertTrue("chi-square test -- will fail about 1 in 1000 times",
testStatistic.chiSquare(expected,observed) < 10.828);
}
public void testNextFloat() {
Frequency freq = new Frequency();
float val = 0;
int value = 0;
for (int i=0; i<smallSampleSize; i++) {
val = testGenerator.nextFloat();
if (val < 0.25) {
value = 0;
} else if (val < 0.5) {
value = 1;
} else if (val < 0.75) {
value = 2;
} else {
value = 3;
}
freq.addValue(value);
}
long[] observed = new long[4];
for (int i=0; i<4; i++) {
observed[i] = freq.getCount(i);
}
/* Use ChiSquare dist with df = 4-1 = 3, alpha = .001
* Change to 11.34 for alpha = .01
*/
assertTrue("chi-square test -- will fail about 1 in 1000 times",
testStatistic.chiSquare(expected,observed) < 16.27);
}
}