public void testReciprocal() {
Fraction f = null;
f = new Fraction(50, 75);
f = f.reciprocal();
assertEquals(3, f.getNumerator());
assertEquals(2, f.getDenominator());
f = new Fraction(4, 3);
f = f.reciprocal();
assertEquals(3, f.getNumerator());
assertEquals(4, f.getDenominator());
f = new Fraction(-15, 47);
f = f.reciprocal();
assertEquals(-47, f.getNumerator());
assertEquals(15, f.getDenominator());
f = new Fraction(0, 3);
try {
f = f.reciprocal();
fail("expecting ArithmeticException");
} catch (ArithmeticException ex) {
}
// large values
f = new Fraction(Integer.MAX_VALUE, 1);
f = f.reciprocal();
assertEquals(1, f.getNumerator());
assertEquals(Integer.MAX_VALUE, f.getDenominator());
}
public void testDivide() {
Fraction a = new Fraction(1, 2);
Fraction b = new Fraction(2, 3);
assertFraction(1, 1, a.divide(a));
assertFraction(3, 4, a.divide(b));
assertFraction(4, 3, b.divide(a));
assertFraction(1, 1, b.divide(b));
Fraction f1 = new Fraction(3, 5);
Fraction f2 = Fraction.ZERO;
try {
f1.divide(f2);
fail("expecting ArithmeticException");
} catch (ArithmeticException ex) {
}
f1 = new Fraction(0, 5);
f2 = new Fraction(2, 7);
Fraction f = f1.divide(f2);
assertSame(Fraction.ZERO, f);
f1 = new Fraction(2, 7);
f2 = Fraction.ONE;
f = f1.divide(f2);
assertEquals(2, f.getNumerator());
assertEquals(7, f.getDenominator());
f1 = new Fraction(1, Integer.MAX_VALUE);
f = f1.divide(f1);
assertEquals(1, f.getNumerator());
assertEquals(1, f.getDenominator());
f1 = new Fraction(Integer.MIN_VALUE, Integer.MAX_VALUE);
f2 = new Fraction(1, Integer.MAX_VALUE);
f = f1.divide(f2);
assertEquals(Integer.MIN_VALUE, f.getNumerator());
assertEquals(1, f.getDenominator());
try {
f.divide(null);
fail("IllegalArgumentException");
} catch (IllegalArgumentException ex) {
}
try {
f1 = new Fraction(1, Integer.MAX_VALUE);
f = f1.divide(f1.reciprocal()); // should overflow
fail("expecting ArithmeticException");
} catch (ArithmeticException ex) {
}
try {
f1 = new Fraction(1, -Integer.MAX_VALUE);
f = f1.divide(f1.reciprocal()); // should overflow
fail("expecting ArithmeticException");
} catch (ArithmeticException ex) {
}
}
/**
* Divide the value of this fraction by another.
*
* @param fraction the fraction to divide by, must not be <code>null</code>
* @return a <code>Fraction</code> instance with the resulting values
* @throws IllegalArgumentException if the fraction is <code>null</code>
* @throws ArithmeticException if the fraction to divide by is zero
* @throws ArithmeticException if the resulting numerator or denominator exceeds <code>
* Integer.MAX_VALUE</code>
*/
public Fraction divide(Fraction fraction) {
if (fraction == null) {
throw MathRuntimeException.createIllegalArgumentException("null fraction");
}
if (fraction.numerator == 0) {
throw MathRuntimeException.createArithmeticException(
"the fraction to divide by must not be zero: {0}/{1}",
fraction.numerator, fraction.denominator);
}
return multiply(fraction.reciprocal());
}
