加载中...
The Wayback Machine - https://sup1a9wrlpyh5li9ro.vcoronado.top/web/20090405184402/http://developer.android.com:80/reference/java/lang/Math.html
public final class

Math

extends Object
java.lang.Object
   ↳ java.lang.Math

Class Overview

Class math provides various floating point support routines and some standard constants.

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 d1, double d2)
Returns the remainder of dividing the first argument by the second 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
static double asin(double d)
Returns the closest double approximation of the arc sine of the argument
static double atan(double d)
Returns the closest double approximation of the arc tangent of the argument
static double atan2(double d1, double d2)
Returns the closest double approximation of the arc tangent of the result of dividing the first argument by the second argument.
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 (i.e.
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 ed - 1.
static double floor(double d)
Returns the double conversion of the most positive (i.e.
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 (i.e.
static int max(int i1, int i2)
Returns the most positive (i.e.
static float max(float f1, float f2)
Returns the most positive (i.e.
static long max(long l1, long l2)
Returns the most positive (i.e.
static double min(double d1, double d2)
Returns the most negative (i.e.
static long min(long l1, long l2)
Returns the most negative (i.e.
static float min(float f1, float f2)
Returns the most negative (i.e.
static int min(int i1, int i2)
Returns the most negative (i.e.
static double pow(double d1, double d2)
Returns the closest double approximation of the result of raising the first argument to the power of the second.
static double random()
Returns a pseudo-random number between 0.0 and 1.0.
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.
static double ulp(double d)
Returns the argument's ulp.
[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 d1, double d2)

Returns the remainder of dividing the first argument by the second using the IEEE 754 rules.

Parameters
d1 the numerator of the operation
d2 the denominator of the operation
Returns
  • the result of d1/d2.

public static float abs (float f)

Returns the absolute value of the argument.

Parameters
f the value to be converted
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.

Parameters
l the value to be converted
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.

Parameters
i the value to be converted
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.

Parameters
d the value to be converted
Returns
  • the argument if it is positive, otherwise the negation of the argument.

public static double acos (double d)

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

Parameters
d the value to compute acos 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

Parameters
d the value to compute asin of
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

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

public static double atan2 (double d1, double d2)

Returns the closest double approximation of the arc tangent of the result of dividing the first argument by the second argument.

Parameters
d1 the numerator of the value to compute atan of
d2 the denominator of the value to compute atan of
Returns
  • the arc tangent of d1/d2.

public static double cbrt (double d)

Returns the closest double approximation of the cube root of the argument. The final result should be within 1ulp of the real result.

Parameters
d the value to compute cube root of
Returns
  • the cube root of the argument.

public static double ceil (double d)

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

Parameters
d the value to be converted
Returns
  • the ceiling of the argument.

public static double cos (double d)

Returns the closest double approximation of the cosine of the argument

Parameters
d the angle to compute the cosine of, 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. The final result should be within 2.5ulps of the real result.

Parameters
d the value to compute hyperbolic cosine of
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

Parameters
d the value to compute the exponential of
Returns
  • the exponential of the argument.

public static double expm1 (double d)

Returns the closest double approximation of ed - 1. If the argument is very close to 0, it is much more accurate to use expm1(d)+1 than exp(d). The final result should be within 1 ulp of the real result. For any finite input, the result should be no less than -1.0. If the real result is within 0.5 ulp of -1, -1.0 should be answered.

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 (i.e. closest to positive infinity) integer value which is less than the argument.

Parameters
d the value to be converted
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. The final result should be within 1 ulp of the real result. If one parameter remains constant, the result should be semi-monotonic.

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

Parameters
d the value to compute the log of
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

Parameters
d the value to compute the log10 of
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). The final result should be within 1 ulp of the real result and be semi-monotonic.

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 (i.e. closest to positive infinity) of the two arguments.

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

public static int max (int i1, int i2)

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

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

public static float max (float f1, float f2)

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

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

public static long max (long l1, long l2)

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

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

public static double min (double d1, double d2)

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

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

public static long min (long l1, long l2)

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

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

public static float min (float f1, float f2)

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

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

public static int min (int i1, int i2)

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

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

public static double pow (double d1, double d2)

Returns the closest double approximation of the result of raising the first argument to the power of the second.

Parameters
d1 the base of the operation.
d2 the exponent of the operation.
Returns
  • d1 to the power of d2

public static double random ()

Returns a pseudo-random number between 0.0 and 1.0.

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.

Parameters
d the value to be converted
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.

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

public static int round (float f)

Returns the result of rounding the argument to an integer.

Parameters
f the value to be converted
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 greater than zero, 1.0 is returned. It returns zero if the argument is also zero.

Parameters
d the value to compute signum function of
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 greater than zero, 1.0 is returned. It returns zero if the argument is also zero.

Parameters
f the value to compute signum function of
Returns
  • the value of the signum function.

public static double sin (double d)

Returns the closest double approximation of the sine of the argument

Parameters
d the angle to compute the sine of, 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. The final result should be within 2.5ulps of the real result.

Parameters
d the value to compute hyperbolic sine of
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

Parameters
d the value to compute sqrt of
Returns
  • the square root of the argument.

public static double tan (double d)

Returns the closest double approximation of the tangent of the argument

Parameters
d the angle to compute the tangent of, 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. The final result should be within 2.5ulps of the real result. If the real result is within 0.5ulp of 1 or -1, it should answer exactly +1 or -1.

Parameters
d the value to compute hyperbolic tangent of
Returns
  • the hyperbolic tangent of the argument.

public static double toDegrees (double angrad)

Returns the measure in degrees of the supplied radian angle

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

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

public static float ulp (float f)

Returns the argument's ulp. 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).

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. 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).

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