Examples with BigInteger java.math.BigInteger used on opensource projects

Example 66 with BigInteger

use of java.math.BigInteger in project guava by google.

the class LongMathTest method testCheckedAdd.

// slow
@AndroidIncompatible
// TODO
@GwtIncompatible
public void testCheckedAdd() {
    for (long a : ALL_LONG_CANDIDATES) {
        for (long b : ALL_LONG_CANDIDATES) {
            BigInteger expectedResult = valueOf(a).add(valueOf(b));
            boolean expectedSuccess = fitsInLong(expectedResult);
            try {
                assertEquals(a + b, LongMath.checkedAdd(a, b));
                assertTrue(expectedSuccess);
            } catch (ArithmeticException e) {
                if (expectedSuccess) {
                    failFormat("expected checkedAdd(%s, %s) = %s; got ArithmeticException", a, b, expectedResult);
                }
            }
        }
    }
}

Example 67 with BigInteger

use of java.math.BigInteger in project guava by google.

the class LongMathTest method computeMeanSafely.

/**
   * Computes the mean in a way that is obvious and resilient to
   * overflow by using BigInteger arithmetic.
   */
private static long computeMeanSafely(long x, long y) {
    BigInteger bigX = BigInteger.valueOf(x);
    BigInteger bigY = BigInteger.valueOf(y);
    BigDecimal bigMean = new BigDecimal(bigX.add(bigY)).divide(BigDecimal.valueOf(2), BigDecimal.ROUND_FLOOR);
    // parseInt blows up on overflow as opposed to intValue() which does not.
    return Long.parseLong(bigMean.toString());
}

Example 68 with BigInteger

use of java.math.BigInteger in project guava by google.

the class LongMathTest method testCheckedPow.

// TODO
@GwtIncompatible
public void testCheckedPow() {
    for (long b : ALL_LONG_CANDIDATES) {
        for (int exp : EXPONENTS) {
            BigInteger expectedResult = valueOf(b).pow(exp);
            boolean expectedSuccess = fitsInLong(expectedResult);
            try {
                assertEquals(expectedResult.longValue(), LongMath.checkedPow(b, exp));
                assertTrue(expectedSuccess);
            } catch (ArithmeticException e) {
                if (expectedSuccess) {
                    failFormat("expected checkedPow(%s, %s) = %s; got ArithmeticException", b, exp, expectedResult);
                }
            }
        }
    }
}

Example 69 with BigInteger

use of java.math.BigInteger in project guava by google.

the class LongMathTest method testBinomial.

// Depends on the correctness of BigIntegerMath.binomial.
public void testBinomial() {
    for (int n = 0; n <= 70; n++) {
        for (int k = 0; k <= n; k++) {
            BigInteger expectedBig = BigIntegerMath.binomial(n, k);
            long expectedLong = fitsInLong(expectedBig) ? expectedBig.longValue() : Long.MAX_VALUE;
            assertEquals(expectedLong, LongMath.binomial(n, k));
        }
    }
}

Example 70 with BigInteger

use of java.math.BigInteger in project guava by google.

the class IntMathTest method testFactorial.

// Depends on the correctness of BigIntegerMath.factorial.
public void testFactorial() {
    for (int n = 0; n <= 50; n++) {
        BigInteger expectedBig = BigIntegerMath.factorial(n);
        int expectedInt = fitsInInt(expectedBig) ? expectedBig.intValue() : Integer.MAX_VALUE;
        assertEquals(expectedInt, IntMath.factorial(n));
    }
}