[LANG-663] org.apache.commons.lang3.math.Fraction does not always succeed in multiplyBy and divideBy

• Type: Bug
• Status: Closed
• Priority: Minor
• Resolution: Fixed
• Affects Version/s: 3.0
• Fix Version/s: 3.0
• Component/s: lang.math.*
• Assignee: Unassigned
• Reporter: Christian Semrau
• Created: 06/Dec/10 23:15
• Updated: 17/Jan/11 04:13
• Resolved: 17/Jan/11 04:13

Description

The Fraction.multiplyBy and divideBy methods fail sometimes when the arguments are not reduced.

FunctionTest.java

    public void testMultiply() {
        // ...
        f1 = Fraction.getFraction(Integer.MAX_VALUE, Integer.MAX_VALUE);
        f2 = Fraction.getFraction(42, 1);
        f = f1.multiplyBy(f2);
        assertEquals(42, f.getNumerator());
        assertEquals(1, f.getDenominator());

    public void testDivide() {
        // ...
        f1 = Fraction.getFraction(Integer.MAX_VALUE, Integer.MAX_VALUE);
        f2 = Fraction.getFraction(42, 1);
        f = f1.divideBy(f2);
        assertEquals(1, f.getNumerator());
        assertEquals(42, f.getDenominator());

Issue Links

• duplicates: MATH-251 Improve the Fraction class to avoid overflow problems and increase features
• is related to: LANG-662 org.apache.commons.lang3.math.Fraction does not reduce (Integer.MIN_VALUE, 2^k)