public final class

StrictMath

extends Object
java.lang.Object
   ↳ java.lang.StrictMath

Class Overview

Class StrictMath provides basic math constants and operations such as trigonometric functions, hyperbolic functions, exponential, logarithms, etc.

In contrast to class Math, the methods in this class return exactly the same results on all platforms. Algorithms based on these methods thus behave the same (e.g. regarding numerical convergence) on all platforms, complying with the slogan "write once, run everywhere". On the other side, the implementation of class StrictMath may be less efficient than that of class Math, as class StrictMath cannot utilize platform specific features such as an extended precision math co-processors.

The methods in this class are specified using the "Freely Distributable Math Library" (fdlibm), version 5.3.

http://www.netlib.org/fdlibm/

Summary

Constants
double E The double value closest to e, the base of the natural logarithm.
double PI The double value closest to pi, the ratio of a circle's circumference to its diameter.
Public Methods
static double IEEEremainder(double x, double y)
Returns the remainder of dividing x by y using the IEEE 754 rules.
static float abs(float f)
Returns the absolute value of the argument.
static long abs(long l)
Returns the absolute value of the argument.
static int abs(int i)
Returns the absolute value of the argument.
static double abs(double d)
Returns the absolute value of the argument.
static double acos(double d)
Returns the closest double approximation of the arc cosine of the argument within the range [0..pi].
static double asin(double d)
Returns the closest double approximation of the arc sine of the argument within the range [-pi/2..pi/2].
static double atan(double d)
Returns the closest double approximation of the arc tangent of the argument within the range [-pi/2..pi/2].
static double atan2(double y, double x)
Returns the closest double approximation of the arc tangent of y/x within the range [-pi..pi].
static double cbrt(double d)
Returns the closest double approximation of the cube root of the argument.
static double ceil(double d)
Returns the double conversion of the most negative (closest to negative infinity) integer value which is greater than the argument.
static double cos(double d)
Returns the closest double approximation of the cosine of the argument.
static double cosh(double d)
Returns the closest double approximation of the hyperbolic cosine of the argument.
static double exp(double d)
Returns the closest double approximation of the raising "e" to the power of the argument.
static double expm1(double d)
Returns the closest double approximation of e d- 1.
static double floor(double d)
Returns the double conversion of the most positive (closest to positive infinity) integer value which is less than the argument.
static double hypot(double x, double y)
Returns sqrt(x2+ y2).
static double log(double d)
Returns the closest double approximation of the natural logarithm of the argument.
static double log10(double d)
Returns the closest double approximation of the base 10 logarithm of the argument.
static double log1p(double d)
Returns the closest double approximation of the natural logarithm of the sum of the argument and 1.
static double max(double d1, double d2)
Returns the most positive (closest to positive infinity) of the two arguments.
static int max(int i1, int i2)
Returns the most positive (closest to positive infinity) of the two arguments.
static float max(float f1, float f2)
Returns the most positive (closest to positive infinity) of the two arguments.
static long max(long l1, long l2)
Returns the most positive (closest to positive infinity) of the two arguments.
static double min(double d1, double d2)
Returns the most negative (closest to negative infinity) of the two arguments.
static long min(long l1, long l2)
Returns the most negative (closest to negative infinity) of the two arguments.
static float min(float f1, float f2)
Returns the most negative (closest to negative infinity) of the two arguments.
static int min(int i1, int i2)
Returns the most negative (closest to negative infinity) of the two arguments.
static double pow(double x, double y)
Returns the closest double approximation of the result of raising x to the power of y.
static double random()
Returns a pseudo-random number between 0.0 (inclusive) and 1.0 (exclusive).
static double rint(double d)
Returns the double conversion of the result of rounding the argument to an integer.
static long round(double d)
Returns the result of rounding the argument to an integer.
static int round(float f)
Returns the result of rounding the argument to an integer.
static double signum(double d)
Returns the signum function of the argument.
static float signum(float f)
Returns the signum function of the argument.
static double sin(double d)
Returns the closest double approximation of the sine of the argument.
static double sinh(double d)
Returns the closest double approximation of the hyperbolic sine of the argument.
static double sqrt(double d)
Returns the closest double approximation of the square root of the argument.
static double tan(double d)
Returns the closest double approximation of the tangent of the argument.
static double tanh(double d)
Returns the closest double approximation of the hyperbolic tangent of the argument.
static double toDegrees(double angrad)
Returns the measure in degrees of the supplied radian angle.
static double toRadians(double angdeg)
Returns the measure in radians of the supplied degree angle.
static float ulp(float f)
Returns the argument's ulp (unit in the last place).
static double ulp(double d)
Returns the argument's ulp (unit in the last place).
[Expand]
Inherited Methods
From class java.lang.Object

Constants

public static final double E

The double value closest to e, the base of the natural logarithm.

Constant Value: 2.718281828459045

public static final double PI

The double value closest to pi, the ratio of a circle's circumference to its diameter.

Constant Value: 3.141592653589793

Public Methods

public static double IEEEremainder (double x, double y)

Returns the remainder of dividing x by y using the IEEE 754 rules. The result is x-round(x/p)*p where round(x/p) is the nearest integer (rounded to even), but without numerical cancellation problems.

Special cases:

  • IEEEremainder((anything), 0) = NaN
  • IEEEremainder(+infinity, (anything)) = NaN
  • IEEEremainder(-infinity, (anything)) = NaN
  • IEEEremainder(NaN, (anything)) = NaN
  • IEEEremainder((anything), NaN) = NaN
  • IEEEremainder(x, +infinity) = x where x is anything but +/-infinity
  • IEEEremainder(x, -infinity) = x where x is anything but +/-infinity

Parameters
x the numerator of the operation.
y the denominator of the operation.
Returns
  • the IEEE754 floating point reminder of of x/y.

public static float abs (float f)

Returns the absolute value of the argument.

Special cases:

  • abs(-0.0) = +0.0
  • abs(+infinity) = +infinity
  • abs(-infinity) = +infinity
  • abs(NaN) = NaN

Parameters
f the value whose absolute value has to be computed.
Returns
  • the argument if it is positive, otherwise the negation of the argument.

public static long abs (long l)

Returns the absolute value of the argument.

If the argument is Long.MIN_VALUE, Long.MIN_VALUE is returned.

Parameters
l the value whose absolute value has to be computed.
Returns
  • the argument if it is positive, otherwise the negation of the argument.

public static int abs (int i)

Returns the absolute value of the argument.

If the argument is Integer.MIN_VALUE, Integer.MIN_VALUE is returned.

Parameters
i the value whose absolute value has to be computed.
Returns
  • the argument if it is positive, otherwise the negation of the argument.

public static double abs (double d)

Returns the absolute value of the argument.

Special cases:

  • abs(-0.0) = +0.0
  • abs(+infinity) = +infinity
  • abs(-infinity) = +infinity
  • abs(NaN) = NaN

Parameters
d the value whose absolute value has to be computed.
Returns
  • the absolute value of the argument.

public static double acos (double d)

Returns the closest double approximation of the arc cosine of the argument within the range [0..pi].

Special cases:

  • acos((anything > 1) = NaN
  • acos((anything < -1) = NaN
  • acos(NaN) = NaN

Parameters
d the value to compute arc cosine of.
Returns
  • the arc cosine of the argument.

public static double asin (double d)

Returns the closest double approximation of the arc sine of the argument within the range [-pi/2..pi/2].

Special cases:

  • asin((anything > 1)) = NaN
  • asin((anything < -1)) = NaN
  • asin(NaN) = NaN

Parameters
d the value whose arc sine has to be computed.
Returns
  • the arc sine of the argument.

public static double atan (double d)

Returns the closest double approximation of the arc tangent of the argument within the range [-pi/2..pi/2].

Special cases:

  • atan(+0.0) = +0.0
  • atan(-0.0) = -0.0
  • atan(+infinity) = +pi/2
  • atan(-infinity) = -pi/2
  • atan(NaN) = NaN

Parameters
d the value whose arc tangent has to be computed.
Returns
  • the arc tangent of the argument.

public static double atan2 (double y, double x)

Returns the closest double approximation of the arc tangent of y/x within the range [-pi..pi]. This is the angle of the polar representation of the rectangular coordinates (x,y).

Special cases:

  • atan2((anything), NaN ) = NaN;
  • atan2(NaN , (anything) ) = NaN;
  • atan2(+0.0, +(anything but NaN)) = +0.0
  • atan2(-0.0, +(anything but NaN)) = -0.0
  • atan2(+0.0, -(anything but NaN)) = +pi
  • atan2(-0.0, -(anything but NaN)) = -pi
  • atan2(+(anything but 0 and NaN), 0) = +pi/2
  • atan2(-(anything but 0 and NaN), 0) = -pi/2
  • atan2(+(anything but infinity and NaN), +infinity) = +0.0
  • atan2(-(anything but infinity and NaN), +infinity) = -0.0
  • atan2(+(anything but infinity and NaN), -infinity) = +pi
  • atan2(-(anything but infinity and NaN), -infinity) = -pi
  • atan2(+infinity, +infinity ) = +pi/4
  • atan2(-infinity, +infinity ) = -pi/4
  • atan2(+infinity, -infinity ) = +3pi/4
  • atan2(-infinity, -infinity ) = -3pi/4
  • atan2(+infinity, (anything but,0, NaN, and infinity)) = +pi/2
  • atan2(-infinity, (anything but,0, NaN, and infinity)) = -pi/2

Parameters
y the numerator of the value whose atan has to be computed.
x the denominator of the value whose atan has to be computed.
Returns
  • the arc tangent of y/x.

public static double cbrt (double d)

Returns the closest double approximation of the cube root of the argument.

Special cases:

  • cbrt(+0.0) = +0.0
  • cbrt(-0.0) = -0.0
  • cbrt(+infinity) = +infinity
  • cbrt(-infinity) = -infinity
  • cbrt(NaN) = NaN

Parameters
d the value whose cube root has to be computed.
Returns
  • the cube root of the argument.

public static double ceil (double d)

Returns the double conversion of the most negative (closest to negative infinity) integer value which is greater than the argument.

Special cases:

  • ceil(+0.0) = +0.0
  • ceil(-0.0) = -0.0
  • ceil((anything in range (-1,0)) = -0.0
  • ceil(+infinity) = +infinity
  • ceil(-infinity) = -infinity
  • ceil(NaN) = NaN

Parameters
d the value whose closest integer value has to be computed.
Returns
  • the ceiling of the argument.

public static double cos (double d)

Returns the closest double approximation of the cosine of the argument.

Special cases:

  • cos(+infinity) = NaN
  • cos(-infinity) = NaN
  • cos(NaN) = NaN

Parameters
d the angle whose cosine has to be computed, in radians.
Returns
  • the cosine of the argument.

public static double cosh (double d)

Returns the closest double approximation of the hyperbolic cosine of the argument.

Special cases:

  • cosh(+infinity) = +infinity
  • cosh(-infinity) = +infinity
  • cosh(NaN) = NaN

Parameters
d the value whose hyperbolic cosine has to be computed.
Returns
  • the hyperbolic cosine of the argument.

public static double exp (double d)

Returns the closest double approximation of the raising "e" to the power of the argument.

Special cases:

  • exp(+infinity) = +infinity
  • exp(-infinity) = +0.0
  • exp(NaN) = NaN

Parameters
d the value whose exponential has to be computed.
Returns
  • the exponential of the argument.

public static double expm1 (double d)

Returns the closest double approximation of e d- 1. If the argument is very close to 0, it is much more accurate to use expm1(d)+1 than exp(d) (due to cancellation of significant digits).

Special cases:

  • expm1(+0.0) = +0.0
  • expm1(-0.0) = -0.0
  • expm1(+infinity) = +infinity
  • expm1(-infinity) = -1.0
  • expm1(NaN) = NaN

Parameters
d the value to compute the ed - 1 of.
Returns
  • the ed- 1 value of the argument.

public static double floor (double d)

Returns the double conversion of the most positive (closest to positive infinity) integer value which is less than the argument.

Special cases:

  • floor(+0.0) = +0.0
  • floor(-0.0) = -0.0
  • floor(+infinity) = +infinity
  • floor(-infinity) = -infinity
  • floor(NaN) = NaN

Parameters
d the value whose closest integer value has to be computed.
Returns
  • the floor of the argument.

public static double hypot (double x, double y)

Returns sqrt(x2+ y2). The final result is without medium underflow or overflow.

Special cases:

  • hypot(+infinity, (anything including NaN)) = +infinity
  • hypot(-infinity, (anything including NaN)) = +infinity
  • hypot((anything including NaN), +infinity) = +infinity
  • hypot((anything including NaN), -infinity) = +infinity
  • hypot(NaN, NaN) = NaN

Parameters
x a double number.
y a double number.
Returns
  • the sqrt(x2+ y2) value of the arguments.

public static double log (double d)

Returns the closest double approximation of the natural logarithm of the argument.

Special cases:

  • log(+0.0) = -infinity
  • log(-0.0) = -infinity
  • log((anything < 0) = NaN
  • log(+infinity) = +infinity
  • log(-infinity) = NaN
  • log(NaN) = NaN

Parameters
d the value whose log has to be computed.
Returns
  • the natural logarithm of the argument.

public static double log10 (double d)

Returns the closest double approximation of the base 10 logarithm of the argument.

Special cases:

  • log10(+0.0) = -infinity
  • log10(-0.0) = -infinity
  • log10((anything < 0) = NaN
  • log10(+infinity) = +infinity
  • log10(-infinity) = NaN
  • log10(NaN) = NaN

Parameters
d the value whose base 10 log has to be computed.
Returns
  • the natural logarithm of the argument.

public static double log1p (double d)

Returns the closest double approximation of the natural logarithm of the sum of the argument and 1. If the argument is very close to 0, it is much more accurate to use log1p(d) than log(1.0+d) (due to numerical cancellation).

Special cases:

  • log1p(+0.0) = +0.0
  • log1p(-0.0) = -0.0
  • log1p((anything < 1)) = NaN
  • log1p(-1.0) = -infinity
  • log1p(+infinity) = +infinity
  • log1p(-infinity) = NaN
  • log1p(NaN) = NaN

Parameters
d the value to compute the ln(1+d) of.
Returns
  • the natural logarithm of the sum of the argument and 1.

public static double max (double d1, double d2)

Returns the most positive (closest to positive infinity) of the two arguments.

Special cases:

  • max(NaN, (anything)) = NaN
  • max((anything), NaN) = NaN
  • max(+0.0, -0.0) = +0.0
  • max(-0.0, +0.0) = +0.0

Parameters
d1 the first argument.
d2 the second argument.
Returns
  • the larger of d1 and d2.

public static int max (int i1, int i2)

Returns the most positive (closest to positive infinity) of the two arguments.

Parameters
i1 the first argument.
i2 the second argument.
Returns
  • the larger of i1 and i2.

public static float max (float f1, float f2)

Returns the most positive (closest to positive infinity) of the two arguments.

Special cases:

  • max(NaN, (anything)) = NaN
  • max((anything), NaN) = NaN
  • max(+0.0, -0.0) = +0.0
  • max(-0.0, +0.0) = +0.0

Parameters
f1 the first argument.
f2 the second argument.
Returns
  • the larger of f1 and f2.

public static long max (long l1, long l2)

Returns the most positive (closest to positive infinity) of the two arguments.

Parameters
l1 the first argument.
l2 the second argument.
Returns
  • the larger of l1 and l2.

public static double min (double d1, double d2)

Returns the most negative (closest to negative infinity) of the two arguments.

Special cases:

  • min(NaN, (anything)) = NaN
  • min((anything), NaN) = NaN
  • min(+0.0, -0.0) = -0.0
  • min(-0.0, +0.0) = -0.0

Parameters
d1 the first argument.
d2 the second argument.
Returns
  • the smaller of d1 and d2.

public static long min (long l1, long l2)

Returns the most negative (closest to negative infinity) of the two arguments.

Parameters
l1 the first argument.
l2 the second argument.
Returns
  • the smaller of l1 and l2.

public static float min (float f1, float f2)

Returns the most negative (closest to negative infinity) of the two arguments.

Special cases:

  • min(NaN, (anything)) = NaN
  • min((anything), NaN) = NaN
  • min(+0.0, -0.0) = -0.0
  • min(-0.0, +0.0) = -0.0

Parameters
f1 the first argument.
f2 the second argument.
Returns
  • the smaller of f1 and f2.

public static int min (int i1, int i2)

Returns the most negative (closest to negative infinity) of the two arguments.

Parameters
i1 the first argument.
i2 the second argument.
Returns
  • the smaller of i1 and i2.

public static double pow (double x, double y)

Returns the closest double approximation of the result of raising x to the power of y.

Special cases:

  • pow((anything), +0.0) = 1.0
  • pow((anything), -0.0) = 1.0
  • pow(x, 1.0) = x
  • pow((anything), NaN) = NaN
  • pow(NaN, (anything except 0)) = NaN
  • pow(+/-(|x| > 1), +infinity) = +infinity
  • pow(+/-(|x| > 1), -infinity) = +0.0
  • pow(+/-(|x| < 1), +infinity) = +0.0
  • pow(+/-(|x| < 1), -infinity) = +infinity
  • pow(+/-1.0 , +infinity) = NaN
  • pow(+/-1.0 , -infinity) = NaN
  • pow(+0.0, (+anything except 0, NaN)) = +0.0
  • pow(-0.0, (+anything except 0, NaN, odd integer)) = +0.0
  • pow(+0.0, (-anything except 0, NaN)) = +infinity
  • pow(-0.0, (-anything except 0, NAN, odd integer)) = +infinity
  • pow(-0.0, (odd integer)) = -pow( +0 , (odd integer) )
  • pow(+infinity, (+anything except 0, NaN)) = +infinity
  • pow(+infinity, (-anything except 0, NaN)) = +0.0
  • pow(-infinity, (anything)) = -pow(0, (-anything))
  • pow((-anything), (integer)) = pow(-1,(integer))*pow(+anything,integer)
  • pow((-anything except 0 and infinity), (non-integer)) = NAN

Parameters
x the base of the operation.
y the exponent of the operation.
Returns
  • x to the power of y.

public static double random ()

Returns a pseudo-random number between 0.0 (inclusive) and 1.0 (exclusive).

Returns
  • a pseudo-random number.

public static double rint (double d)

Returns the double conversion of the result of rounding the argument to an integer. Tie breaks are rounded towards even.

Special cases:

  • rint(+0.0) = +0.0
  • rint(-0.0) = -0.0
  • rint(+infinity) = +infinity
  • rint(-infinity) = -infinity
  • rint(NaN) = NaN

Parameters
d the value to be rounded.
Returns
  • the closest integer to the argument (as a double).

public static long round (double d)

Returns the result of rounding the argument to an integer. The result is equivalent to (long) Math.floor(d+0.5).

Special cases:

  • round(+0.0) = +0.0
  • round(-0.0) = +0.0
  • round((anything > Long.MAX_VALUE) = Long.MAX_VALUE
  • round((anything < Long.MIN_VALUE) = Long.MIN_VALUE
  • round(+infinity) = Long.MAX_VALUE
  • round(-infinity) = Long.MIN_VALUE
  • round(NaN) = +0.0

Parameters
d the value to be rounded.
Returns
  • the closest integer to the argument.

public static int round (float f)

Returns the result of rounding the argument to an integer. The result is equivalent to (int) Math.floor(f+0.5).

Special cases:

  • round(+0.0) = +0.0
  • round(-0.0) = +0.0
  • round((anything > Integer.MAX_VALUE) = Integer.MAX_VALUE
  • round((anything < Integer.MIN_VALUE) = Integer.MIN_VALUE
  • round(+infinity) = Integer.MAX_VALUE
  • round(-infinity) = Integer.MIN_VALUE
  • round(NaN) = +0.0

Parameters
f the value to be rounded.
Returns
  • the closest integer to the argument.

public static double signum (double d)

Returns the signum function of the argument. If the argument is less than zero, it returns -1.0. If the argument is greater than zero, 1.0 is returned. If the argument is either positive or negative zero, the argument is returned as result.

Special cases:

  • signum(+0.0) = +0.0
  • signum(-0.0) = -0.0
  • signum(+infinity) = +1.0
  • signum(-infinity) = -1.0
  • signum(NaN) = NaN

Parameters
d the value whose signum has to be computed.
Returns
  • the value of the signum function.

public static float signum (float f)

Returns the signum function of the argument. If the argument is less than zero, it returns -1.0. If the argument is greater than zero, 1.0 is returned. If the argument is either positive or negative zero, the argument is returned as result.

Special cases:

  • signum(+0.0) = +0.0
  • signum(-0.0) = -0.0
  • signum(+infinity) = +1.0
  • signum(-infinity) = -1.0
  • signum(NaN) = NaN

Parameters
f the value whose signum has to be computed.
Returns
  • the value of the signum function.

public static double sin (double d)

Returns the closest double approximation of the sine of the argument.

Special cases:

  • sin(+0.0) = +0.0
  • sin(-0.0) = -0.0
  • sin(+infinity) = NaN
  • sin(-infinity) = NaN
  • sin(NaN) = NaN

Parameters
d the angle whose sin has to be computed, in radians.
Returns
  • the sine of the argument.

public static double sinh (double d)

Returns the closest double approximation of the hyperbolic sine of the argument.

Special cases:

  • sinh(+0.0) = +0.0
  • sinh(-0.0) = -0.0
  • sinh(+infinity) = +infinity
  • sinh(-infinity) = -infinity
  • sinh(NaN) = NaN

Parameters
d the value whose hyperbolic sine has to be computed.
Returns
  • the hyperbolic sine of the argument.

public static double sqrt (double d)

Returns the closest double approximation of the square root of the argument.

Special cases:

  • sqrt(+0.0) = +0.0
  • sqrt(-0.0) = -0.0
  • sqrt( (anything < 0) ) = NaN
  • sqrt(+infinity) = +infinity
  • sqrt(NaN) = NaN

Parameters
d the value whose square root has to be computed.
Returns
  • the square root of the argument.

public static double tan (double d)

Returns the closest double approximation of the tangent of the argument.

Special cases:

  • tan(+0.0) = +0.0
  • tan(-0.0) = -0.0
  • tan(+infinity) = NaN
  • tan(-infinity) = NaN
  • tan(NaN) = NaN

Parameters
d the angle whose tangens has to be computed, in radians.
Returns
  • the tangent of the argument.

public static double tanh (double d)

Returns the closest double approximation of the hyperbolic tangent of the argument. The absolute value is always less than 1.

Special cases:

  • tanh(+0.0) = +0.0
  • tanh(-0.0) = -0.0
  • tanh(+infinity) = +1.0
  • tanh(-infinity) = -1.0
  • tanh(NaN) = NaN

Parameters
d the value whose hyperbolic tangent has to be computed.
Returns
  • the hyperbolic tangent of the argument

public static double toDegrees (double angrad)

Returns the measure in degrees of the supplied radian angle. The result is angrad * 180 / pi.

Special cases:

  • toDegrees(+0.0) = +0.0
  • toDegrees(-0.0) = -0.0
  • toDegrees(+infinity) = +infinity
  • toDegrees(-infinity) = -infinity
  • toDegrees(NaN) = NaN

Parameters
angrad an angle in radians.
Returns
  • the degree measure of the angle.

public static double toRadians (double angdeg)

Returns the measure in radians of the supplied degree angle. The result is angdeg / 180 * pi.

Special cases:

  • toRadians(+0.0) = +0.0
  • toRadians(-0.0) = -0.0
  • toRadians(+infinity) = +infinity
  • toRadians(-infinity) = -infinity
  • toRadians(NaN) = NaN

Parameters
angdeg an angle in degrees.
Returns
  • the radian measure of the angle.

public static float ulp (float f)

Returns the argument's ulp (unit in the last place). The size of a ulp of a float value is the positive distance between this value and the float value next larger in magnitude. For non-NaN x, ulp(-x) == ulp(x).

Special cases:

  • ulp(+0.0) = Float.MIN_VALUE
  • ulp(-0.0) = Float.MIN_VALUE
  • ulp(+infintiy) = infinity
  • ulp(-infintiy) = infinity
  • ulp(NaN) = NaN

Parameters
f the floating-point value to compute ulp of.
Returns
  • the size of a ulp of the argument.

public static double ulp (double d)

Returns the argument's ulp (unit in the last place). The size of a ulp of a double value is the positive distance between this value and the double value next larger in magnitude. For non-NaN x, ulp(-x) == ulp(x).

Special cases:

  • ulp(+0.0) = Double.MIN_VALUE
  • ulp(-0.0) = Double.MIN_VALUE
  • ulp(+infintiy) = infinity
  • ulp(-infintiy) = infinity
  • ulp(NaN) = NaN

Parameters
d the floating-point value to compute ulp of.
Returns
  • the size of a ulp of the argument.