1 /*
2 * Copyright (c) 1998, 2011, Oracle and/or its affiliates. All rights reserved.
3 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
4 *
5 * This code is free software; you can redistribute it and/or modify it
6 * under the terms of the GNU General Public License version 2 only, as
7 * published by the Free Software Foundation.
8 *
9 * This code is distributed in the hope that it will be useful, but WITHOUT
10 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
11 * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
12 * version 2 for more details (a copy is included in the LICENSE file that
13 * accompanied this code).
14 *
15 * You should have received a copy of the GNU General Public License version
16 * 2 along with this work; if not, write to the Free Software Foundation,
17 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
18 *
19 * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
20 * or visit www.oracle.com if you need additional information or have any
21 * questions.
22 */
23
24 /*
25 * @test
26 * @bug 4101566 4831589
27 * @summary Check for correct implementation of Math.rint(double)
28 */
29
30 public class Rint {
31
32 static int testRintCase(double input, double expected) {
33 int failures = 0;
34 double result;
35 failures += Tests.test("Math.rint", input, Math.rint(input), expected);
36 failures += Tests.test("Math.rint", -input, Math.rint(-input), -expected);
37 failures += Tests.test("StrictMath.rint",
38 input, StrictMath.rint(input), expected);
39 failures += Tests.test("StrictMath.rint", -input,
40 StrictMath.rint(-input), -expected);
41 return failures;
42 }
43
44
45 public static void main(String args[]) {
46 int failures = 0;
47 double twoToThe52 = Math.scalb(1.0, 52); // 2^52
48
49 double [][] testCases = {
50 {0.0, 0.0},
51 {Double.MIN_VALUE, 0.0},
52 {Math.nextDown(Double.MIN_NORMAL), 0.0},
53 {Double.MIN_NORMAL, 0.0},
54
55 {0.2, 0.0},
56
57 {Math.nextDown(0.5), 0.0},
58 { 0.5, 0.0},
59 { Math.nextUp(0.5), 1.0},
60
61 {0.7, 1.0},
62 {Math.nextDown(1.0), 1.0},
63 { 1.0, 1.0},
64 { Math.nextUp(1.0), 1.0},
65
66 {Math.nextDown(1.5), 1.0},
67 { 1.5, 2.0},
68 { Math.nextUp(1.5), 2.0},
69
70 {4.2, 4.0},
71 {4.5, 4.0},
72 {4.7, 5.0},
73
74 {7.5, 8.0},
75 {7.2, 7.0},
76 {7.7, 8.0},
77
78 {150000.75, 150001.0},
79 {300000.5, 300000.0},
80 {Math.nextUp(300000.5), 300001.0},
81 {Math.nextDown(300000.75), 300001.0},
82 {300000.75, 300001.0},
83 {Math.nextUp(300000.75), 300001.0},
84 {300000.99, 300001.0},
85 {262144.75, 262145.0}, //(2^18 ) + 0.75
86 {499998.75, 499999.0},
87 {524287.75, 524288.0}, //(2^19 -1) + 0.75
88 {524288.75, 524289.0},
89
90 {Math.nextDown(twoToThe52), twoToThe52},
91 {twoToThe52, twoToThe52},
92 {Math.nextUp(twoToThe52), Math.nextUp(twoToThe52)},
93
94 {Double.MAX_VALUE, Double.MAX_VALUE},
95 {Double.POSITIVE_INFINITY, Double.POSITIVE_INFINITY},
96 {Double.NaN, Double.NaN}
97
98 };
99
100
101 for(int i = 0; i < testCases.length; i++) {
102 failures += testRintCase(testCases[i][0], testCases[i][1]);
103 }
104
105 // Test values throughout exponent range
106 for(double d = Double.MIN_VALUE;
107 d < Double.POSITIVE_INFINITY; d *= 2) {
108 failures += testRintCase(d, ((d<=0.5)?0.0:d));
109 }
110
111 if (failures > 0) {
112 System.err.println("Testing {Math, StrictMath}.rint incurred "
113 + failures + " failures.");
114 throw new RuntimeException();
115 }
116 }
117 }