Quelle PrecisionTests.java Sprache: JAVA

/*
* Copyright (c) 2009, 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.
*/

/*
* @test
* @bug 1234567
* @summary Test that precision() is computed properly.
* @author Joseph D. Darcy
*/

import java.math.*;
import static java.math.BigDecimal.*;

public class PrecisionTests {
    private static BigDecimal NINE = valueOf(9);

    public static void main(String argv[]) {
        int failures = 0;

        // Smallest and largest values of a given length
        BigDecimal[] testValues = {
            valueOf(1), valueOf(9),
        };

        failures += testPrecision(new BigDecimal(0), 1);

        for(int i = 1; i < 100; i++) {
            for(BigDecimal bd : testValues) {
                failures += testPrecision(bd, i);
                failures += testPrecision(bd.negate(), i);
            }

            testValues[0] = testValues[0].multiply(TEN);
            testValues[1] = testValues[1].multiply(TEN).add(NINE);
        }

        // The following test tries to cover testings for precision of long values
        BigDecimal[] randomTestValues = {
            valueOf(2147483648L),          // 2^31:       10 digits
            valueOf(-2147483648L),         // -2^31:      10 digits
            valueOf(98893745455L),         // random:     11 digits
            valueOf(3455436789887L),       // random:     13 digits
            valueOf(140737488355328L),     // 2^47:       15 digits
            valueOf(-140737488355328L),    // -2^47:      15 digits
            valueOf(7564232235739573L),    // random:     16 digits
            valueOf(25335434990002322L),   // random:     17 digits
            valueOf(9223372036854775807L), // 2^63 - 1:   19 digits
            valueOf(-9223372036854775807L) // -2^63 + 1:  19 digits
        };
        // The array below contains the expected precision of the above numbers
        int[] expectedPrecision = {10, 10, 11, 13, 15, 15, 16, 17, 19, 19};
        for (int i = 0; i < randomTestValues.length; i++) {
            failures += testPrecision(randomTestValues[i], expectedPrecision[i]);
        }

        if (failures > 0) {
            throw new RuntimeException("Incurred " + failures +
                                       " failures while testing precision.");
        }
    }

    private static int testPrecision(BigDecimal bd, int expected) {
        int precision = bd.precision();

        // System.out.printf("Testing %s, expected %d%n", bd, expected);

        if (precision != expected) {
            System.err.printf("For (%s).precision expected %d, got %d%n",
                               bd, expected, precision);
            return 1;
        }
        return 0;
    }
}

quality87%

¤ Dauer der Verarbeitung: 0.12 Sekunden (vorverarbeitet) ¤

Wurzel

Suchen

Beweissystem der NASA

Beweissystem Isabelle

NIST Cobol Testsuite

Cephes Mathematical Library

Wiener Entwicklungsmethode

Haftungshinweis

Die Informationen auf dieser Webseite wurden nach bestem Wissen sorgfältig zusammengestellt. Es wird jedoch weder Vollständigkeit, noch Richtigkeit, noch Qualität der bereit gestellten Informationen zugesichert.

Bemerkung:

Die farbliche Syntaxdarstellung ist noch experimentell.