1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
|
/*
* Copyright (c) 2022, Oracle and/or its affiliates. All rights reserved.
* DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
*
* This code is free software; you can redistribute it and/or modify it
* under the terms of the GNU General Public License version 2 only, as
* published by the Free Software Foundation.
*
* This code is distributed in the hope that it will be useful, but WITHOUT
* ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
* FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
* version 2 for more details (a copy is included in the LICENSE file that
* accompanied this code).
*
* You should have received a copy of the GNU General Public License version
* 2 along with this work; if not, write to the Free Software Foundation,
* Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
*
* Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
* or visit www.oracle.com if you need additional information or have any
* questions.
*/
import jdk.test.lib.RandomFactory;
/**
* @test
* @summary Check that nextExponential() returns non-negative outcomes
* @bug 8284866
*
* @key randomness
* @library /test/lib
* @build jdk.test.lib.RandomFactory
* @run main RandomExponentialTest
*/
public class RandomExponentialTest {
private static final int SAMPLES = 1_000_000_000;
public static void main(String[] args) throws Exception {
var errCount = 0;
var errSample = Double.NaN;
var random = RandomFactory.getRandom();
for (int i = 0; i < SAMPLES; i++) {
var expVal = random.nextExponential();
if (!(expVal >= 0.0)) {
errCount += 1;
errSample = expVal;
}
}
if (errCount > 0) {
throw new RuntimeException("%d errors out of %d samples: e.g., %f"
.formatted(errCount, SAMPLES, errSample));
}
}
}
|
