public void testFuzzyEqualsOneNaN() {
for (double a : DOUBLE_CANDIDATES_EXCEPT_NAN) {
for (double tolerance : TOLERANCE_CANDIDATES) {
assertFalse(DoubleMath.fuzzyEquals(a, Double.NaN, tolerance));
assertFalse(DoubleMath.fuzzyEquals(Double.NaN, a, tolerance));
}
}
}
public void testFuzzyInfiniteVersusInfiniteWithFiniteTolerance() {
for (double inf : INFINITIES) {
for (double tolerance : FINITE_TOLERANCE_CANDIDATES) {
assertTrue(DoubleMath.fuzzyEquals(inf, inf, tolerance));
assertFalse(DoubleMath.fuzzyEquals(inf, -inf, tolerance));
}
}
}
public void testIsPowerOfTwo() {
for (double x : ALL_DOUBLE_CANDIDATES) {
boolean expected =
x > 0
&& !Double.isInfinite(x)
&& !Double.isNaN(x)
&& StrictMath.pow(2.0, DoubleMath.log2(x, FLOOR)) == x;
assertEquals(expected, DoubleMath.isPowerOfTwo(x));
}
}
public void testFuzzyCompare() {
for (double a : ALL_DOUBLE_CANDIDATES) {
for (double b : ALL_DOUBLE_CANDIDATES) {
for (double tolerance : TOLERANCE_CANDIDATES) {
int expected = DoubleMath.fuzzyEquals(a, b, tolerance) ? 0 : Double.compare(a, b);
int actual = DoubleMath.fuzzyCompare(a, b, tolerance);
assertEquals(Integer.signum(expected), Integer.signum(actual));
}
}
}
}
public void testRoundLog2Exact() {
for (double x : POSITIVE_FINITE_DOUBLE_CANDIDATES) {
boolean isPowerOfTwo = StrictMath.pow(2.0, DoubleMath.log2(x, FLOOR)) == x;
try {
int log2 = DoubleMath.log2(x, UNNECESSARY);
assertEquals(x, Math.scalb(1.0, log2));
assertTrue(isPowerOfTwo);
} catch (ArithmeticException e) {
assertFalse(isPowerOfTwo);
}
}
}
public void testRoundInfiniteToBigIntegerAlwaysFails() {
for (RoundingMode mode : ALL_ROUNDING_MODES) {
try {
DoubleMath.roundToBigInteger(Double.POSITIVE_INFINITY, mode);
fail("Expected ArithmeticException");
} catch (ArithmeticException expected) {
}
try {
DoubleMath.roundToBigInteger(Double.NEGATIVE_INFINITY, mode);
fail("Expected ArithmeticException");
} catch (ArithmeticException expected) {
}
}
}
public void testFactorial() {
for (int i = 0; i <= DoubleMath.MAX_FACTORIAL; i++) {
double actual = BigIntegerMath.factorial(i).doubleValue();
double result = DoubleMath.factorial(i);
assertEquals(actual, result, Math.ulp(actual));
}
}
public void testLog2Accuracy() {
for (double d : POSITIVE_FINITE_DOUBLE_CANDIDATES) {
double dmLog2 = DoubleMath.log2(d);
double trueLog2 = trueLog2(d);
assertTrue(Math.abs(dmLog2 - trueLog2) <= Math.ulp(trueLog2));
}
}
public void testFuzzyEqualsInfiniteTolerance() {
for (double a : DOUBLE_CANDIDATES_EXCEPT_NAN) {
for (double b : DOUBLE_CANDIDATES_EXCEPT_NAN) {
assertTrue(DoubleMath.fuzzyEquals(a, b, Double.POSITIVE_INFINITY));
}
}
}
public void testRoundLog2Half() {
// We don't expect perfect rounding accuracy.
for (int exp : asList(-1022, -50, -1, 0, 1, 2, 3, 4, 100, 1022, 1023)) {
for (RoundingMode mode : asList(HALF_EVEN, HALF_UP, HALF_DOWN)) {
double x = Math.scalb(Math.sqrt(2) + 0.001, exp);
double y = Math.scalb(Math.sqrt(2) - 0.001, exp);
if (exp < 0) {
assertEquals(exp + 1, DoubleMath.log2(x, mode));
assertEquals(exp, DoubleMath.log2(y, mode));
} else {
assertEquals(exp + 1, DoubleMath.log2(x, mode));
assertEquals(exp, DoubleMath.log2(y, mode));
}
}
}
}
public void testRoundLog2Floor() {
for (double d : POSITIVE_FINITE_DOUBLE_CANDIDATES) {
int log2 = DoubleMath.log2(d, FLOOR);
assertTrue(StrictMath.pow(2.0, log2) <= d);
assertTrue(StrictMath.pow(2.0, log2 + 1) > d);
}
}
public void testRoundFractionalDoubleToBigInteger() {
for (double d : FRACTIONAL_DOUBLE_CANDIDATES) {
for (RoundingMode mode : ALL_SAFE_ROUNDING_MODES) {
BigDecimal expected = new BigDecimal(d).setScale(0, mode);
assertEquals(expected.toBigInteger(), DoubleMath.roundToBigInteger(d, mode));
}
}
}
public void testRoundLog2Ceiling() {
for (double d : POSITIVE_FINITE_DOUBLE_CANDIDATES) {
int log2 = DoubleMath.log2(d, CEILING);
assertTrue(StrictMath.pow(2.0, log2) >= d);
double z = StrictMath.pow(2.0, log2 - 1);
assertTrue(z < d);
}
}
public void testRoundExactFractionalDoubleToBigIntegerFails() {
for (double d : FRACTIONAL_DOUBLE_CANDIDATES) {
try {
DoubleMath.roundToBigInteger(d, UNNECESSARY);
fail("Expected ArithmeticException");
} catch (ArithmeticException expected) {
}
}
}
public void testRoundNaNToBigIntegerAlwaysFails() {
for (RoundingMode mode : ALL_ROUNDING_MODES) {
try {
DoubleMath.roundToBigInteger(Double.NaN, mode);
fail("Expected ArithmeticException");
} catch (ArithmeticException expected) {
}
}
}
public void testFactorialNegative() {
for (int n : NEGATIVE_INTEGER_CANDIDATES) {
try {
DoubleMath.factorial(n);
fail("Expected IllegalArgumentException");
} catch (IllegalArgumentException expected) {
}
}
}
public void testFuzzyEqualsFinite() {
for (double a : FINITE_DOUBLE_CANDIDATES) {
for (double b : FINITE_DOUBLE_CANDIDATES) {
for (double tolerance : FINITE_TOLERANCE_CANDIDATES) {
assertEquals(Math.abs(a - b) <= tolerance, DoubleMath.fuzzyEquals(a, b, tolerance));
}
}
}
}
public void testFuzzyCompareBadTolerance() {
for (double tolerance : BAD_TOLERANCE_CANDIDATES) {
try {
DoubleMath.fuzzyCompare(1, 2, tolerance);
fail("Expected IllegalArgumentException");
} catch (IllegalArgumentException expected) {
// success
}
}
}
public void testFuzzyEqualsZeroTolerance() {
// make sure we test -0 tolerance
for (double zero : Doubles.asList(0.0, -0.0)) {
for (double a : ALL_DOUBLE_CANDIDATES) {
for (double b : ALL_DOUBLE_CANDIDATES) {
assertEquals(
a == b || (Double.isNaN(a) && Double.isNaN(b)), DoubleMath.fuzzyEquals(a, b, zero));
}
}
}
}
public void testRoundLog2ThrowsOnNegative() {
for (RoundingMode mode : ALL_ROUNDING_MODES) {
for (double d : POSITIVE_FINITE_DOUBLE_CANDIDATES) {
try {
DoubleMath.log2(-d, mode);
fail("Expected IllegalArgumentException");
} catch (IllegalArgumentException e) {
}
}
}
}
public void testRoundLog2ThrowsOnZerosInfinitiesAndNaN() {
for (RoundingMode mode : ALL_ROUNDING_MODES) {
for (double d :
asList(0.0, -0.0, Double.POSITIVE_INFINITY, Double.NEGATIVE_INFINITY, Double.NaN)) {
try {
DoubleMath.log2(d, mode);
fail("Expected IllegalArgumentException");
} catch (IllegalArgumentException e) {
}
}
}
}
public void testRoundLog2Up() {
for (double d : POSITIVE_FINITE_DOUBLE_CANDIDATES) {
int log2 = DoubleMath.log2(d, UP);
if (d >= 1.0) {
assertTrue(log2 >= 0);
assertTrue(StrictMath.pow(2.0, log2) >= d);
assertTrue(StrictMath.pow(2.0, log2 - 1) < d);
} else {
assertTrue(log2 <= 0);
assertTrue(StrictMath.pow(2.0, log2) <= d);
assertTrue(StrictMath.pow(2.0, log2 + 1) > d);
}
}
}
public void testRoundExactIntegralDoubleToInt() {
for (double d : INTEGRAL_DOUBLE_CANDIDATES) {
BigDecimal expected = new BigDecimal(d).setScale(0, UNNECESSARY);
boolean isInBounds =
expected.compareTo(MAX_INT_AS_BIG_DECIMAL) <= 0
& expected.compareTo(MIN_INT_AS_BIG_DECIMAL) >= 0;
try {
assertEquals(expected.intValue(), DoubleMath.roundToInt(d, UNNECESSARY));
assertTrue(isInBounds);
} catch (ArithmeticException e) {
assertFalse(isInBounds);
}
}
}
public void testRoundFractionalDoubleToInt() {
for (double d : FRACTIONAL_DOUBLE_CANDIDATES) {
for (RoundingMode mode : ALL_SAFE_ROUNDING_MODES) {
BigDecimal expected = new BigDecimal(d).setScale(0, mode);
boolean isInBounds =
expected.compareTo(MAX_INT_AS_BIG_DECIMAL) <= 0
& expected.compareTo(MIN_INT_AS_BIG_DECIMAL) >= 0;
try {
assertEquals(expected.intValue(), DoubleMath.roundToInt(d, mode));
assertTrue(isInBounds);
} catch (ArithmeticException e) {
assertFalse(isInBounds);
}
}
}
}
public void testIsMathematicalIntegerIntegral() {
for (double d : INTEGRAL_DOUBLE_CANDIDATES) {
assertTrue(DoubleMath.isMathematicalInteger(d));
}
}
public void testLog2NaNInfinity() {
assertEquals(Double.POSITIVE_INFINITY, DoubleMath.log2(Double.POSITIVE_INFINITY));
assertTrue(Double.isNaN(DoubleMath.log2(Double.NEGATIVE_INFINITY)));
assertTrue(Double.isNaN(DoubleMath.log2(Double.NaN)));
}
public void testIsMathematicalIntegerFractional() {
for (double d : FRACTIONAL_DOUBLE_CANDIDATES) {
assertFalse(DoubleMath.isMathematicalInteger(d));
}
}
public void testIsMathematicalIntegerNotFinite() {
for (double d : Arrays.asList(Double.POSITIVE_INFINITY, Double.NEGATIVE_INFINITY, Double.NaN)) {
assertFalse(DoubleMath.isMathematicalInteger(d));
}
}
public void testFuzzyEqualsTwoNaNs() {
for (double tolerance : TOLERANCE_CANDIDATES) {
assertTrue(DoubleMath.fuzzyEquals(Double.NaN, Double.NaN, tolerance));
}
}
public void testFactorialTooHigh() {
assertEquals(Double.POSITIVE_INFINITY, DoubleMath.factorial(DoubleMath.MAX_FACTORIAL + 1));
assertEquals(Double.POSITIVE_INFINITY, DoubleMath.factorial(DoubleMath.MAX_FACTORIAL + 20));
}