Class: java.lang.StrictMath

  • public final class StrictMath
The class StrictMath contains methods for performing basic numeric operations such as the elementary exponential, logarithm, square root, and trigonometric functions.

To help ensure portability of Java programs, the definitions of some of the numeric functions in this package require that they produce the same results as certain published algorithms. These algorithms are available from the well-known network library netlib as the package "Freely Distributable Math Library," fdlibm. These algorithms, which are written in the C programming language, are then to be understood as executed with all floating-point operations following the rules of Java floating-point arithmetic.

The Java math library is defined with respect to fdlibm version 5.3. Where fdlibm provides more than one definition for a function (such as acos), use the "IEEE 754 core function" version (residing in a file whose name begins with the letter e). The methods which require fdlibm semantics are sin, cos, tan, asin, acos, atan, exp, log, log10, cbrt, atan2, pow, sinh, cosh, tanh, hypot, expm1, and log1p.

Authors:
@author unascribed
@author Joseph D. Darcy
Since:
@since 1.3

Inheritance

Superclass tree:

Methods

  • IEEEremaindertop

    public static native double IEEEremainder(double f1, double f2)
    Computes the remainder operation on two arguments as prescribed by the IEEE 754 standard. The remainder value is mathematically equal to f1 - f2 × n, where n is the mathematical integer closest to the exact mathematical value of the quotient f1/f2, and if two mathematical integers are equally close to f1/f2, then n is the integer that is even. If the remainder is zero, its sign is the same as the sign of the first argument. Special cases:
    • If either argument is NaN, or the first argument is infinite, or the second argument is positive zero or negative zero, then the result is NaN.
    • If the first argument is finite and the second argument is infinite, then the result is the same as the first argument.
    Parameters:
    @param f1 the dividend.
    @param f2 the divisor.
    Return:
    @return the remainder when f1 is divided by f2 .
    Related Links:
    Google Code Search
    Stack Overflow

  • abstop

    public static double abs(double a)
    Returns the absolute value of a double value. If the argument is not negative, the argument is returned. If the argument is negative, the negation of the argument is returned. Special cases:
    • If the argument is positive zero or negative zero, the result is positive zero.
    • If the argument is infinite, the result is positive infinity.
    • If the argument is NaN, the result is NaN.
    In other words, the result is the same as the value of the expression:

    Double.longBitsToDouble((Double.doubleToLongBits(a)<<1)>>>1)

    Parameters:
    @param a the argument whose absolute value is to be determined
    Return:
    @return the absolute value of the argument.
    Related Links:
    Google Code Search
    Stack Overflow

  • abstop

    public static float abs(float a)
    Returns the absolute value of a float value. If the argument is not negative, the argument is returned. If the argument is negative, the negation of the argument is returned. Special cases:
    • If the argument is positive zero or negative zero, the result is positive zero.
    • If the argument is infinite, the result is positive infinity.
    • If the argument is NaN, the result is NaN.
    In other words, the result is the same as the value of the expression:

    Float.intBitsToFloat(0x7fffffff & Float.floatToIntBits(a))

    Parameters:
    @param a the argument whose absolute value is to be determined
    Return:
    @return the absolute value of the argument.
    Related Links:
    Google Code Search
    Stack Overflow

  • abstop

    public static int abs(int a)
    Returns the absolute value of an int value.. If the argument is not negative, the argument is returned. If the argument is negative, the negation of the argument is returned.

    Note that if the argument is equal to the value of Integer.MIN_VALUE, the most negative representable int value, the result is that same value, which is negative.

    Parameters:
    @param a the argument whose absolute value is to be determined.
    Return:
    @return the absolute value of the argument.
    Related Links:
    Google Code Search
    Stack Overflow

  • abstop

    public static long abs(long a)
    Returns the absolute value of a long value. If the argument is not negative, the argument is returned. If the argument is negative, the negation of the argument is returned.

    Note that if the argument is equal to the value of Long.MIN_VALUE, the most negative representable long value, the result is that same value, which is negative.

    Parameters:
    @param a the argument whose absolute value is to be determined.
    Return:
    @return the absolute value of the argument.
    Related Links:
    Google Code Search
    Stack Overflow

  • acostop

    public static native double acos(double a)
    Returns the arc cosine of a value; the returned angle is in the range 0.0 through pi. Special case:
    • If the argument is NaN or its absolute value is greater than 1, then the result is NaN.
    Parameters:
    @param a the value whose arc cosine is to be returned.
    Return:
    @return the arc cosine of the argument.
    Related Links:
    Google Code Search
    Stack Overflow

  • asintop

    public static native double asin(double a)
    Returns the arc sine of a value; the returned angle is in the range -pi/2 through pi/2. Special cases:
    • If the argument is NaN or its absolute value is greater than 1, then the result is NaN.
    • If the argument is zero, then the result is a zero with the same sign as the argument.
    Parameters:
    @param a the value whose arc sine is to be returned.
    Return:
    @return the arc sine of the argument.
    Related Links:
    Google Code Search
    Stack Overflow

  • atantop

    public static native double atan(double a)
    Returns the arc tangent of a value; the returned angle is in the range -pi/2 through pi/2. Special cases:
    • If the argument is NaN, then the result is NaN.
    • If the argument is zero, then the result is a zero with the same sign as the argument.
    Parameters:
    @param a the value whose arc tangent is to be returned.
    Return:
    @return the arc tangent of the argument.
    Related Links:
    Google Code Search
    Stack Overflow

  • atan2top

    public static native double atan2(double y, double x)
    Returns the angle theta from the conversion of rectangular coordinates (x, y) to polar coordinates (r, theta). This method computes the phase theta by computing an arc tangent of y/x in the range of -pi to pi. Special cases:
    • If either argument is NaN, then the result is NaN.
    • If the first argument is positive zero and the second argument is positive, or the first argument is positive and finite and the second argument is positive infinity, then the result is positive zero.
    • If the first argument is negative zero and the second argument is positive, or the first argument is negative and finite and the second argument is positive infinity, then the result is negative zero.
    • If the first argument is positive zero and the second argument is negative, or the first argument is positive and finite and the second argument is negative infinity, then the result is the double value closest to pi.
    • If the first argument is negative zero and the second argument is negative, or the first argument is negative and finite and the second argument is negative infinity, then the result is the double value closest to -pi.
    • If the first argument is positive and the second argument is positive zero or negative zero, or the first argument is positive infinity and the second argument is finite, then the result is the double value closest to pi/2.
    • If the first argument is negative and the second argument is positive zero or negative zero, or the first argument is negative infinity and the second argument is finite, then the result is the double value closest to -pi/2.
    • If both arguments are positive infinity, then the result is the double value closest to pi/4.
    • If the first argument is positive infinity and the second argument is negative infinity, then the result is the double value closest to 3*pi/4.
    • If the first argument is negative infinity and the second argument is positive infinity, then the result is the double value closest to -pi/4.
    • If both arguments are negative infinity, then the result is the double value closest to -3*pi/4.
    Parameters:
    @param y the ordinate coordinate
    @param x the abscissa coordinate
    Return:
    @return the theta component of the point (r, theta) in polar coordinates that corresponds to the point (x, y) in Cartesian coordinates.
    Related Links:
    Google Code Search
    Stack Overflow

  • cbrttop

    public static native double cbrt(double a)
    Returns the cube root of a double value. For positive finite x, cbrt(-x) == -cbrt(x); that is, the cube root of a negative value is the negative of the cube root of that value's magnitude. Special cases:
    • If the argument is NaN, then the result is NaN.
    • If the argument is infinite, then the result is an infinity with the same sign as the argument.
    • If the argument is zero, then the result is a zero with the same sign as the argument.
    Parameters:
    @param a a value.
    Return:
    @return the cube root of a .
    Since:
    @since 1.5
    Related Links:
    Google Code Search
    Stack Overflow

  • ceiltop

    public static native double ceil(double a)
    Returns the smallest (closest to negative infinity) double value that is greater than or equal to the argument and is equal to a mathematical integer. Special cases:
    • If the argument value is already equal to a mathematical integer, then the result is the same as the argument.
    • If the argument is NaN or an infinity or positive zero or negative zero, then the result is the same as the argument.
    • If the argument value is less than zero but greater than -1.0, then the result is negative zero.
    Note that the value of StrictMath.ceil(x) is exactly the value of -StrictMath.floor(-x).
    Parameters:
    @param a a value.
    Return:
    @return the smallest (closest to negative infinity) floating-point value that is greater than or equal to the argument and is equal to a mathematical integer.
    Related Links:
    Google Code Search
    Stack Overflow

  • copySigntop

    public static double copySign(double magnitude, double sign)
    Returns the first floating-point argument with the sign of the second floating-point argument. For this method, a NaN sign argument is always treated as if it were positive.
    Parameters:
    @param magnitude the parameter providing the magnitude of the result
    @param sign the parameter providing the sign of the result
    Return:
    @return a value with the magnitude of magnitude and the sign of sign .
    Since:
    @since 1.6
    Related Links:
    Google Code Search
    Stack Overflow

  • copySigntop

    public static float copySign(float magnitude, float sign)
    Returns the first floating-point argument with the sign of the second floating-point argument. For this method, a NaN sign argument is always treated as if it were positive.
    Parameters:
    @param magnitude the parameter providing the magnitude of the result
    @param sign the parameter providing the sign of the result
    Return:
    @return a value with the magnitude of magnitude and the sign of sign .
    Since:
    @since 1.6
    Related Links:
    Google Code Search
    Stack Overflow

  • costop

    public static native double cos(double a)
    Returns the trigonometric cosine of an angle. Special cases:
    • If the argument is NaN or an infinity, then the result is NaN.
    Parameters:
    @param a an angle, in radians.
    Return:
    @return the cosine of the argument.
    Related Links:
    Google Code Search
    Stack Overflow

  • coshtop

    public static native double cosh(double x)
    Returns the hyperbolic cosine of a double value. The hyperbolic cosine of x is defined to be (ex + e-x)/2 where e is Euler's number.

    Special cases:

    • If the argument is NaN, then the result is NaN.
    • If the argument is infinite, then the result is positive infinity.
    • If the argument is zero, then the result is 1.0.
    Parameters:
    @param x The number whose hyperbolic cosine is to be returned.
    Return:
    @return The hyperbolic cosine of x .
    Since:
    @since 1.5
    Related Links:
    Google Code Search
    Stack Overflow

  • exptop

    public static native double exp(double a)
    Returns Euler's number e raised to the power of a double value. Special cases:
    • If the argument is NaN, the result is NaN.
    • If the argument is positive infinity, then the result is positive infinity.
    • If the argument is negative infinity, then the result is positive zero.
    Parameters:
    @param a the exponent to raise e to.
    Return:
    @return the value e a , where e is the base of the natural logarithms.
    Related Links:
    Google Code Search
    Stack Overflow

  • expm1top

    public static native double expm1(double x)
    Returns ex -1. Note that for values of x near 0, the exact sum of expm1(x) + 1 is much closer to the true result of ex than exp(x).

    Special cases:

    • If the argument is NaN, the result is NaN.
    • If the argument is positive infinity, then the result is positive infinity.
    • If the argument is negative infinity, then the result is -1.0.
    • If the argument is zero, then the result is a zero with the same sign as the argument.
    Parameters:
    @param x the exponent to raise e to in the computation of e x  -1.
    Return:
    @return the value e x  - 1.
    Since:
    @since 1.5
    Related Links:
    Google Code Search
    Stack Overflow

  • floortop

    public static native double floor(double a)
    Returns the largest (closest to positive infinity) double value that is less than or equal to the argument and is equal to a mathematical integer. Special cases:
    • If the argument value is already equal to a mathematical integer, then the result is the same as the argument.
    • If the argument is NaN or an infinity or positive zero or negative zero, then the result is the same as the argument.
    Parameters:
    @param a a value.
    Return:
    @return the largest (closest to positive infinity) floating-point value that less than or equal to the argument and is equal to a mathematical integer.
    Related Links:
    Google Code Search
    Stack Overflow

  • getExponenttop

    public static int getExponent(double d)
    Returns the unbiased exponent used in the representation of a double. Special cases:
    Parameters:
    @param d a double value
    Since:
    @since 1.6
    Related Links:
    Google Code Search
    Stack Overflow

  • getExponenttop

    public static int getExponent(float f)
    Returns the unbiased exponent used in the representation of a float. Special cases:
    Parameters:
    @param f a float value
    Since:
    @since 1.6
    Related Links:
    Google Code Search
    Stack Overflow

  • hypottop

    public static native double hypot(double x, double y)
    Returns sqrt(x2 +y2) without intermediate overflow or underflow.

    Special cases:

    • If either argument is infinite, then the result is positive infinity.
    • If either argument is NaN and neither argument is infinite, then the result is NaN.
    Parameters:
    @param x a value
    @param y a value
    Return:
    @return sqrt(x2 +y2) without intermediate overflow or underflow
    Since:
    @since 1.5
    Related Links:
    Google Code Search
    Stack Overflow

  • logtop

    public static native double log(double a)
    Returns the natural logarithm (base e) of a double value. Special cases:
    • If the argument is NaN or less than zero, then the result is NaN.
    • If the argument is positive infinity, then the result is positive infinity.
    • If the argument is positive zero or negative zero, then the result is negative infinity.
    Parameters:
    @param a a value
    Return:
    @return the value ln  a , the natural logarithm of a .
    Related Links:
    Google Code Search
    Stack Overflow

  • log10top

    public static native double log10(double a)
    Returns the base 10 logarithm of a double value. Special cases:
    • If the argument is NaN or less than zero, then the result is NaN.
    • If the argument is positive infinity, then the result is positive infinity.
    • If the argument is positive zero or negative zero, then the result is negative infinity.
    • If the argument is equal to 10n for integer n, then the result is n.
    Parameters:
    @param a a value
    Return:
    @return the base 10 logarithm of a .
    Since:
    @since 1.5
    Related Links:
    Google Code Search
    Stack Overflow

  • log1ptop

    public static native double log1p(double x)
    Returns the natural logarithm of the sum of the argument and 1. Note that for small values x, the result of log1p(x) is much closer to the true result of ln(1 + x) than the floating-point evaluation of log(1.0+x).

    Special cases:

    • If the argument is NaN or less than -1, then the result is NaN.
    • If the argument is positive infinity, then the result is positive infinity.
    • If the argument is negative one, then the result is negative infinity.
    • If the argument is zero, then the result is a zero with the same sign as the argument.
    Parameters:
    @param x a value
    Return:
    @return the value ln( x  + 1), the natural log of x  + 1
    Since:
    @since 1.5
    Related Links:
    Google Code Search
    Stack Overflow

  • maxtop

    public static double max(double a, double b)
    Returns the greater of two double values. That is, the result is the argument closer to positive infinity. If the arguments have the same value, the result is that same value. If either value is NaN, then the result is NaN. Unlike the numerical comparison operators, this method considers negative zero to be strictly smaller than positive zero. If one argument is positive zero and the other negative zero, the result is positive zero.
    Parameters:
    @param a an argument.
    @param b another argument.
    Return:
    @return the larger of a and b .
    Related Links:
    Google Code Search
    Stack Overflow

  • maxtop

    public static float max(float a, float b)
    Returns the greater of two float values. That is, the result is the argument closer to positive infinity. If the arguments have the same value, the result is that same value. If either value is NaN, then the result is NaN. Unlike the numerical comparison operators, this method considers negative zero to be strictly smaller than positive zero. If one argument is positive zero and the other negative zero, the result is positive zero.
    Parameters:
    @param a an argument.
    @param b another argument.
    Return:
    @return the larger of a and b .
    Related Links:
    Google Code Search
    Stack Overflow

  • maxtop

    public static int max(int a, int b)
    Returns the greater of two int values. That is, the result is the argument closer to the value of Integer.MAX_VALUE. If the arguments have the same value, the result is that same value.
    Parameters:
    @param a an argument.
    @param b another argument.
    Return:
    @return the larger of a and b .
    Related Links:
    Google Code Search
    Stack Overflow

  • maxtop

    public static long max(long a, long b)
    Returns the greater of two long values. That is, the result is the argument closer to the value of Long.MAX_VALUE. If the arguments have the same value, the result is that same value.
    Parameters:
    @param a an argument.
    @param b another argument.
    Return:
    @return the larger of a and b .
    Related Links:
    Google Code Search
    Stack Overflow

  • mintop

    public static double min(double a, double b)
    Returns the smaller of two double values. That is, the result is the value closer to negative infinity. If the arguments have the same value, the result is that same value. If either value is NaN, then the result is NaN. Unlike the numerical comparison operators, this method considers negative zero to be strictly smaller than positive zero. If one argument is positive zero and the other is negative zero, the result is negative zero.
    Parameters:
    @param a an argument.
    @param b another argument.
    Return:
    @return the smaller of a and b .
    Related Links:
    Google Code Search
    Stack Overflow

  • mintop

    public static float min(float a, float b)
    Returns the smaller of two float values. That is, the result is the value closer to negative infinity. If the arguments have the same value, the result is that same value. If either value is NaN, then the result is NaN. Unlike the numerical comparison operators, this method considers negative zero to be strictly smaller than positive zero. If one argument is positive zero and the other is negative zero, the result is negative zero.
    Parameters:
    @param a an argument.
    @param b another argument.
    Return:
    @return the smaller of a and b.
    Related Links:
    Google Code Search
    Stack Overflow

  • mintop

    public static int min(int a, int b)
    Returns the smaller of two int values. That is, the result the argument closer to the value of Integer.MIN_VALUE. If the arguments have the same value, the result is that same value.
    Parameters:
    @param a an argument.
    @param b another argument.
    Return:
    @return the smaller of a and b .
    Related Links:
    Google Code Search
    Stack Overflow

  • mintop

    public static long min(long a, long b)
    Returns the smaller of two long values. That is, the result is the argument closer to the value of Long.MIN_VALUE. If the arguments have the same value, the result is that same value.
    Parameters:
    @param a an argument.
    @param b another argument.
    Return:
    @return the smaller of a and b .
    Related Links:
    Google Code Search
    Stack Overflow

  • nextAftertop

    public static double nextAfter(double start, double direction)
    Returns the floating-point number adjacent to the first argument in the direction of the second argument. If both arguments compare as equal the second argument is returned.

    Special cases:

    • If either argument is a NaN, then NaN is returned.
    • If both arguments are signed zeros, direction is returned unchanged (as implied by the requirement of returning the second argument if the arguments compare as equal).
    • If start is ±Double.MIN_VALUE and direction has a value such that the result should have a smaller magnitude, then a zero with the same sign as start is returned.
    • If start is infinite and direction has a value such that the result should have a smaller magnitude, Double.MAX_VALUE with the same sign as start is returned.
    • If start is equal to ± Double.MAX_VALUE and direction has a value such that the result should have a larger magnitude, an infinity with same sign as start is returned.
    Parameters:
    @param start starting floating-point value
    @param direction value indicating which of start 's neighbors or start should be returned
    Return:
    @return The floating-point number adjacent to start in the direction of direction .
    Since:
    @since 1.6
    Related Links:
    Google Code Search
    Stack Overflow

  • nextAftertop

    public static float nextAfter(float start, double direction)
    Returns the floating-point number adjacent to the first argument in the direction of the second argument. If both arguments compare as equal a value equivalent to the second argument is returned.

    Special cases:

    • If either argument is a NaN, then NaN is returned.
    • If both arguments are signed zeros, a value equivalent to direction is returned.
    • If start is ±Float.MIN_VALUE and direction has a value such that the result should have a smaller magnitude, then a zero with the same sign as start is returned.
    • If start is infinite and direction has a value such that the result should have a smaller magnitude, Float.MAX_VALUE with the same sign as start is returned.
    • If start is equal to ± Float.MAX_VALUE and direction has a value such that the result should have a larger magnitude, an infinity with same sign as start is returned.
    Parameters:
    @param start starting floating-point value
    @param direction value indicating which of start 's neighbors or start should be returned
    Return:
    @return The floating-point number adjacent to start in the direction of direction .
    Since:
    @since 1.6
    Related Links:
    Google Code Search
    Stack Overflow

  • nextUptop

    public static double nextUp(double d)
    Returns the floating-point value adjacent to d in the direction of positive infinity. This method is semantically equivalent to nextAfter(d, Double.POSITIVE_INFINITY); however, a nextUp implementation may run faster than its equivalent nextAfter call.

    Special Cases:

    • If the argument is NaN, the result is NaN.
    • If the argument is positive infinity, the result is positive infinity.
    • If the argument is zero, the result is Double.MIN_VALUE
    Parameters:
    @param d starting floating-point value
    Return:
    @return The adjacent floating-point value closer to positive infinity.
    Since:
    @since 1.6
    Related Links:
    Google Code Search
    Stack Overflow

  • nextUptop

    public static float nextUp(float f)
    Returns the floating-point value adjacent to f in the direction of positive infinity. This method is semantically equivalent to nextAfter(f, Float.POSITIVE_INFINITY); however, a nextUp implementation may run faster than its equivalent nextAfter call.

    Special Cases:

    • If the argument is NaN, the result is NaN.
    • If the argument is positive infinity, the result is positive infinity.
    • If the argument is zero, the result is Float.MIN_VALUE
    Parameters:
    @param f starting floating-point value
    Return:
    @return The adjacent floating-point value closer to positive infinity.
    Since:
    @since 1.6
    Related Links:
    Google Code Search
    Stack Overflow

  • powtop

    public static native double pow(double a, double b)
    Returns the value of the first argument raised to the power of the second argument. Special cases:
    • If the second argument is positive or negative zero, then the result is 1.0.
    • If the second argument is 1.0, then the result is the same as the first argument.
    • If the second argument is NaN, then the result is NaN.
    • If the first argument is NaN and the second argument is nonzero, then the result is NaN.
    • If
      • the absolute value of the first argument is greater than 1 and the second argument is positive infinity, or
      • the absolute value of the first argument is less than 1 and the second argument is negative infinity,
      then the result is positive infinity.
    • If
      • the absolute value of the first argument is greater than 1 and the second argument is negative infinity, or
      • the absolute value of the first argument is less than 1 and the second argument is positive infinity,
      then the result is positive zero.
    • If the absolute value of the first argument equals 1 and the second argument is infinite, then the result is NaN.
    • If
      • the first argument is positive zero and the second argument is greater than zero, or
      • the first argument is positive infinity and the second argument is less than zero,
      then the result is positive zero.
    • If
      • the first argument is positive zero and the second argument is less than zero, or
      • the first argument is positive infinity and the second argument is greater than zero,
      then the result is positive infinity.
    • If
      • the first argument is negative zero and the second argument is greater than zero but not a finite odd integer, or
      • the first argument is negative infinity and the second argument is less than zero but not a finite odd integer,
      then the result is positive zero.
    • If
      • the first argument is negative zero and the second argument is a positive finite odd integer, or
      • the first argument is negative infinity and the second argument is a negative finite odd integer,
      then the result is negative zero.
    • If
      • the first argument is negative zero and the second argument is less than zero but not a finite odd integer, or
      • the first argument is negative infinity and the second argument is greater than zero but not a finite odd integer,
      then the result is positive infinity.
    • If
      • the first argument is negative zero and the second argument is a negative finite odd integer, or
      • the first argument is negative infinity and the second argument is a positive finite odd integer,
      then the result is negative infinity.
    • If the first argument is finite and less than zero
      • if the second argument is a finite even integer, the result is equal to the result of raising the absolute value of the first argument to the power of the second argument
      • if the second argument is a finite odd integer, the result is equal to the negative of the result of raising the absolute value of the first argument to the power of the second argument
      • if the second argument is finite and not an integer, then the result is NaN.
    • If both arguments are integers, then the result is exactly equal to the mathematical result of raising the first argument to the power of the second argument if that result can in fact be represented exactly as a double value.

    (In the foregoing descriptions, a floating-point value is considered to be an integer if and only if it is finite and a fixed point of the method ceil or, equivalently, a fixed point of the method floor. A value is a fixed point of a one-argument method if and only if the result of applying the method to the value is equal to the value.)

    Parameters:
    @param a base.
    @param b the exponent.
    Return:
    @return the value a b .
    Related Links:
    Google Code Search
    Stack Overflow

  • randomtop

    public static double random()
    Returns a double value with a positive sign, greater than or equal to 0.0 and less than 1.0. Returned values are chosen pseudorandomly with (approximately) uniform distribution from that range.

    When this method is first called, it creates a single new pseudorandom-number generator, exactly as if by the expression

    new java.util.Random
    This new pseudorandom-number generator is used thereafter for all calls to this method and is used nowhere else.

    This method is properly synchronized to allow correct use by more than one thread. However, if many threads need to generate pseudorandom numbers at a great rate, it may reduce contention for each thread to have its own pseudorandom number generator.

    Return:
    @return a pseudorandom double greater than or equal to 0.0 and less than 1.0 .
    See:
    @see java.util.Random.nextDouble()
    Related Links:
    Google Code Search
    Stack Overflow

  • rinttop

    public static double rint(double a)
    Returns the double value that is closest in value to the argument and is equal to a mathematical integer. If two double values that are mathematical integers are equally close to the value of the argument, the result is the integer value that is even. Special cases:
    • If the argument value is already equal to a mathematical integer, then the result is the same as the argument.
    • If the argument is NaN or an infinity or positive zero or negative zero, then the result is the same as the argument.
    Parameters:
    @param a a value.
    Return:
    @return the closest floating-point value to a that is equal to a mathematical integer.
    Misc:
    @author Joseph D. Darcy
    Related Links:
    Google Code Search
    Stack Overflow

  • roundtop

    public static long round(double a)
    Returns the closest long to the argument. The result is rounded to an integer by adding 1/2, taking the floor of the result, and casting the result to type long. In other words, the result is equal to the value of the expression:

    (long)Math.floor(a + 0.5d)

    Special cases:

    • If the argument is NaN, the result is 0.
    • If the argument is negative infinity or any value less than or equal to the value of Long.MIN_VALUE, the result is equal to the value of Long.MIN_VALUE.
    • If the argument is positive infinity or any value greater than or equal to the value of Long.MAX_VALUE, the result is equal to the value of Long.MAX_VALUE.
    Parameters:
    @param a a floating-point value to be rounded to a long .
    Return:
    @return the value of the argument rounded to the nearest long value.
    See:
    @see Long.MAX_VALUE
    @see Long.MIN_VALUE
    Related Links:
    Google Code Search
    Stack Overflow

  • roundtop

    public static int round(float a)
    Returns the closest int to the argument. The result is rounded to an integer by adding 1/2, taking the floor of the result, and casting the result to type int. In other words, the result is equal to the value of the expression:

    (int)Math.floor(a + 0.5f)

    Special cases:

    • If the argument is NaN, the result is 0.
    • If the argument is negative infinity or any value less than or equal to the value of Integer.MIN_VALUE, the result is equal to the value of Integer.MIN_VALUE.
    • If the argument is positive infinity or any value greater than or equal to the value of Integer.MAX_VALUE, the result is equal to the value of Integer.MAX_VALUE.
    Parameters:
    @param a a floating-point value to be rounded to an integer.
    Return:
    @return the value of the argument rounded to the nearest int value.
    See:
    @see Integer.MAX_VALUE
    @see Integer.MIN_VALUE
    Related Links:
    Google Code Search
    Stack Overflow

  • scalbtop

    public static double scalb(double d, int scaleFactor)
    Return d × 2scaleFactor rounded as if performed by a single correctly rounded floating-point multiply to a member of the double value set. See the Java Language Specification for a discussion of floating-point value sets. If the exponent of the result is between Double.MIN_EXPONENT and Double.MAX_EXPONENT, the answer is calculated exactly. If the exponent of the result would be larger than Double.MAX_EXPONENT, an infinity is returned. Note that if the result is subnormal, precision may be lost; that is, when scalb(x, n) is subnormal, scalb(scalb(x, n), -n) may not equal x. When the result is non-NaN, the result has the same sign as d.

    Special cases:

    • If the first argument is NaN, NaN is returned.
    • If the first argument is infinite, then an infinity of the same sign is returned.
    • If the first argument is zero, then a zero of the same sign is returned.
    Parameters:
    @param d number to be scaled by a power of two.
    @param scaleFactor power of 2 used to scale d
    Return:
    @return d × 2 scaleFactor
    Since:
    @since 1.6
    Related Links:
    Google Code Search
    Stack Overflow

  • scalbtop

    public static float scalb(float f, int scaleFactor)
    Return f × 2scaleFactor rounded as if performed by a single correctly rounded floating-point multiply to a member of the float value set. See the Java Language Specification for a discussion of floating-point value sets. If the exponent of the result is between Float.MIN_EXPONENT and Float.MAX_EXPONENT, the answer is calculated exactly. If the exponent of the result would be larger than Float.MAX_EXPONENT, an infinity is returned. Note that if the result is subnormal, precision may be lost; that is, when scalb(x, n) is subnormal, scalb(scalb(x, n), -n) may not equal x. When the result is non-NaN, the result has the same sign as f.

    Special cases:

    • If the first argument is NaN, NaN is returned.
    • If the first argument is infinite, then an infinity of the same sign is returned.
    • If the first argument is zero, then a zero of the same sign is returned.
    Parameters:
    @param f number to be scaled by a power of two.
    @param scaleFactor power of 2 used to scale f
    Return:
    @return f × 2 scaleFactor
    Since:
    @since 1.6
    Related Links:
    Google Code Search
    Stack Overflow

  • signumtop

    public static double signum(double d)
    Returns the signum function of the argument; zero if the argument is zero, 1.0 if the argument is greater than zero, -1.0 if the argument is less than zero.

    Special Cases:

    • If the argument is NaN, then the result is NaN.
    • If the argument is positive zero or negative zero, then the result is the same as the argument.
    Parameters:
    @param d the floating-point value whose signum is to be returned
    Return:
    @return the signum function of the argument
    Since:
    @since 1.5
    Misc:
    @author Joseph D. Darcy
    Related Links:
    Google Code Search
    Stack Overflow

  • signumtop

    public static float signum(float f)
    Returns the signum function of the argument; zero if the argument is zero, 1.0f if the argument is greater than zero, -1.0f if the argument is less than zero.

    Special Cases:

    • If the argument is NaN, then the result is NaN.
    • If the argument is positive zero or negative zero, then the result is the same as the argument.
    Parameters:
    @param f the floating-point value whose signum is to be returned
    Return:
    @return the signum function of the argument
    Since:
    @since 1.5
    Misc:
    @author Joseph D. Darcy
    Related Links:
    Google Code Search
    Stack Overflow

  • sintop

    public static native double sin(double a)
    Returns the trigonometric sine of an angle. Special cases:
    • If the argument is NaN or an infinity, then the result is NaN.
    • If the argument is zero, then the result is a zero with the same sign as the argument.
    Parameters:
    @param a an angle, in radians.
    Return:
    @return the sine of the argument.
    Related Links:
    Google Code Search
    Stack Overflow

  • sinhtop

    public static native double sinh(double x)
    Returns the hyperbolic sine of a double value. The hyperbolic sine of x is defined to be (ex - e-x)/2 where e is Euler's number.

    Special cases:

    • If the argument is NaN, then the result is NaN.
    • If the argument is infinite, then the result is an infinity with the same sign as the argument.
    • If the argument is zero, then the result is a zero with the same sign as the argument.
    Parameters:
    @param x The number whose hyperbolic sine is to be returned.
    Return:
    @return The hyperbolic sine of x .
    Since:
    @since 1.5
    Related Links:
    Google Code Search
    Stack Overflow

  • sqrttop

    public static native double sqrt(double a)
    Returns the correctly rounded positive square root of a double value. Special cases:
    • If the argument is NaN or less than zero, then the result is NaN.
    • If the argument is positive infinity, then the result is positive infinity.
    • If the argument is positive zero or negative zero, then the result is the same as the argument.
    Otherwise, the result is the double value closest to the true mathematical square root of the argument value.
    Parameters:
    @param a a value.
    Return:
    @return the positive square root of a .
    Related Links:
    Google Code Search
    Stack Overflow

  • tantop

    public static native double tan(double a)
    Returns the trigonometric tangent of an angle. Special cases:
    • If the argument is NaN or an infinity, then the result is NaN.
    • If the argument is zero, then the result is a zero with the same sign as the argument.
    Parameters:
    @param a an angle, in radians.
    Return:
    @return the tangent of the argument.
    Related Links:
    Google Code Search
    Stack Overflow

  • tanhtop

    public static native double tanh(double x)
    Returns the hyperbolic tangent of a double value. The hyperbolic tangent of x is defined to be (ex - e-x)/(ex + e-x), in other words, sinh(x)/cosh(x). Note that the absolute value of the exact tanh is always less than 1.

    Special cases:

    • If the argument is NaN, then the result is NaN.
    • If the argument is zero, then the result is a zero with the same sign as the argument.
    • If the argument is positive infinity, then the result is +1.0.
    • If the argument is negative infinity, then the result is -1.0.
    Parameters:
    @param x The number whose hyperbolic tangent is to be returned.
    Return:
    @return The hyperbolic tangent of x .
    Since:
    @since 1.5
    Related Links:
    Google Code Search
    Stack Overflow

  • toDegreestop

    public static double toDegrees(double angrad)
    Converts an angle measured in radians to an approximately equivalent angle measured in degrees. The conversion from radians to degrees is generally inexact; users should not expect cos(toRadians(90.0)) to exactly equal 0.0.
    Parameters:
    @param angrad an angle, in radians
    Return:
    @return the measurement of the angle angrad in degrees.
    Related Links:
    Google Code Search
    Stack Overflow

  • toRadianstop

    public static double toRadians(double angdeg)
    Converts an angle measured in degrees to an approximately equivalent angle measured in radians. The conversion from degrees to radians is generally inexact.
    Parameters:
    @param angdeg an angle, in degrees
    Return:
    @return the measurement of the angle angdeg in radians.
    Related Links:
    Google Code Search
    Stack Overflow

  • ulptop

    public static double ulp(double d)
    Returns the size of an ulp of the argument. An ulp of a double value is the positive distance between this floating-point value and the double value next larger in magnitude. Note that for non-NaN x, ulp(-x) == ulp(x).

    Special Cases:

    • If the argument is NaN, then the result is NaN.
    • If the argument is positive or negative infinity, then the result is positive infinity.
    • If the argument is positive or negative zero, then the result is Double.MIN_VALUE.
    • If the argument is ±Double.MAX_VALUE, then the result is equal to 2971.
    Parameters:
    @param d the floating-point value whose ulp is to be returned
    Return:
    @return the size of an ulp of the argument
    Since:
    @since 1.5
    Misc:
    @author Joseph D. Darcy
    Related Links:
    Google Code Search
    Stack Overflow

  • ulptop

    public static float ulp(float f)
    Returns the size of an ulp of the argument. An ulp of a float value is the positive distance between this floating-point value and the float value next larger in magnitude. Note that for non-NaN x, ulp(-x) == ulp(x).

    Special Cases:

    • If the argument is NaN, then the result is NaN.
    • If the argument is positive or negative infinity, then the result is positive infinity.
    • If the argument is positive or negative zero, then the result is Float.MIN_VALUE.
    • If the argument is ±Float.MAX_VALUE, then the result is equal to 2104.
    Parameters:
    @param f the floating-point value whose ulp is to be returned
    Return:
    @return the size of an ulp of the argument
    Since:
    @since 1.5
    Misc:
    @author Joseph D. Darcy
    Related Links:
    Google Code Search
    Stack Overflow

Fields

  • E

    public static final double E = 2.718281828459045
    The double value that is closer than any other to e, the base of the natural logarithms.

  • PI

    public static final double PI = 3.141592653589793
    The double value that is closer than any other to pi, the ratio of the circumference of a circle to its diameter.