java.lang
Class StrictMath

java.lang.Object
  |
  +--java.lang.StrictMath

public final class StrictMath
extends Object

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 many 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 network library may be found on the World Wide Web at:

   http://metalab.unc.edu/
 

The Java math library is defined with respect to the version of fdlibm dated January 4, 1995. 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).

Since:
1.3

Field Summary
static double E
copy->  E
The double value that is closer than any other to e, the base of the natural logarithms.
static double PI
copy->  PI
The double value that is closer than any other to pi, the ratio of the circumference of a circle to its diameter.
 
Method Summary
static double abs(double a)
copy->  StrictMath.abs( )
copy->  <double var>=StrictMath.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 equal to the value of the expression:

Double.longBitsToDouble((Double.doubleToLongBits(a)<<1)>>>1)
Parameters:
a - a double value.
Returns:
the absolute value of the argument.
static float abs(float a)
copy->  StrictMath.abs( )
copy->  <float var>=StrictMath.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 equal to the value of the expression:

Float.intBitsToFloat(0x7fffffff & Float.floatToIntBits(a))
Parameters:
a - a float value.
Returns:
the absolute value of the argument.
static int abs(int a)
copy->  StrictMath.abs( )
copy->  <int var>=StrictMath.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:
a - the int argument whose absolute value is to be determined.
Returns:
the absolute value of the argument.
See Also:
Integer.MIN_VALUE
static long abs(long a)
copy->  StrictMath.abs( )
copy->  <long var>=StrictMath.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:
a - a long value.
Returns:
the absolute value of the argument.
See Also:
Long.MIN_VALUE
static double acos(double a)
copy->  StrictMath.acos( )
copy->  <double var>=StrictMath.acos(<double a>);
Returns the arc cosine of an angle, in the range of 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:
a - the double value whose arc cosine is to be returned.
Returns:
the arc cosine of the argument.
static double asin(double a)
copy->  StrictMath.asin( )
copy->  <double var>=StrictMath.asin(<double a>);
Returns the arc sine of an angle, in the range of -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 positive zero, then the result is positive zero; if the argument is negative zero, then the result is negative zero.
Parameters:
a - the double value whose arc sine is to be returned.
Returns:
the arc sine of the argument.
static double atan(double a)
copy->  StrictMath.atan( )
copy->  <double var>=StrictMath.atan(<double a>);
Returns the arc tangent of an angle, in the range of -pi/2 through pi/2. Special cases:
  • If the argument is NaN, then the result is NaN.
  • If the argument is positive zero, then the result is positive zero; if the argument is negative zero, then the result is negative zero.
Parameters:
a - the double value whose arc tangent is to be returned.
Returns:
the arc tangent of the argument.
static double atan2(double a, double b)
copy->  StrictMath.atan2(, )
copy->  <double var>=StrictMath.atan2(<double a>, <double b>);
Converts rectangular coordinates (ba) to polar (r, theta). This method computes the phase theta by computing an arc tangent of a/b 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:
a - a double value.
b - a double value.
Returns:
the theta component of the point (rtheta) in polar coordinates that corresponds to the point (ba) in Cartesian coordinates.
static double ceil(double a)
copy->  StrictMath.ceil( )
copy->  <double var>=StrictMath.ceil(<double a>);
Returns the smallest (closest to negative infinity) double value that is not less than 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 Math.ceil(x) is exactly the value of -Math.floor(-x).
Parameters:
a - a double value.
Returns:
the smallest (closest to negative infinity) double value that is not less than the argument and is equal to a mathematical integer.
static double cos(double a)
copy->  StrictMath.cos( )
copy->  <double var>=StrictMath.cos(<double a>);
Returns the trigonometric cosine of an angle. Special case:
  • If the argument is NaN or an infinity, then the result is NaN.
Parameters:
a - an angle, in radians.
Returns:
the cosine of the argument.
static double exp(double a)
copy->  StrictMath.exp( )
copy->  <double var>=StrictMath.exp(<double a>);
Returns the exponential number e (i.e., 2.718...) 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:
a - a double value.
Returns:
the value ea, where e is the base of the natural logarithms.
static double floor(double a)
copy->  StrictMath.floor( )
copy->  <double var>=StrictMath.floor(<double a>);
Returns the largest (closest to positive infinity) double value that is not greater than 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:
a - a double value.
Returns:
the largest (closest to positive infinity) double value that is not greater than the argument and is equal to a mathematical integer.
static double IEEEremainder(double f1, double f2)
copy->  StrictMath.IEEEremainder(, )
copy->  <double var>=StrictMath.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:
f1 - the dividend.
f2 - the divisor.
Returns:
the remainder when f1 is divided by f2.
static double log(double a)
copy->  StrictMath.log( )
copy->  <double var>=StrictMath.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:
a - a number greater than 0.0.
Returns:
the value ln a, the natural logarithm of a.
static double max(double a, double b)
copy->  StrictMath.max(, )
copy->  <double var>=StrictMath.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 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:
a - a double value.
b - a double value.
Returns:
the larger of a and b.
static float max(float a, float b)
copy->  StrictMath.max(, )
copy->  <float var>=StrictMath.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 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:
a - a float value.
b - a float value.
Returns:
the larger of a and b.
static int max(int a, int b)
copy->  StrictMath.max(, )
copy->  <int var>=StrictMath.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:
a - an int value.
b - an int value.
Returns:
the larger of a and b.
See Also:
Long.MAX_VALUE
static long max(long a, long b)
copy->  StrictMath.max(, )
copy->  <long var>=StrictMath.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 argumens have the same value, the result is that same value.
Parameters:
a - a long value.
b - a long value.
Returns:
the larger of a and b.
See Also:
Long.MAX_VALUE
static double min(double a, double b)
copy->  StrictMath.min(, )
copy->  <double var>=StrictMath.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 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:
a - a double value.
b - a double value.
Returns:
the smaller of a and b.
static float min(float a, float b)
copy->  StrictMath.min(, )
copy->  <float var>=StrictMath.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 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:
a - a float value.
b - a float value.
Returns:
the smaller of a and b.
static int min(int a, int b)
copy->  StrictMath.min(, )
copy->  <int var>=StrictMath.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:
a - an int value.
b - an int value.
Returns:
the smaller of a and b.
See Also:
Long.MIN_VALUE
static long min(long a, long b)
copy->  StrictMath.min(, )
copy->  <long var>=StrictMath.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:
a - a long value.
b - a long value.
Returns:
the smaller of a and b.
See Also:
Long.MIN_VALUE
static double pow(double a, double b)
copy->  StrictMath.pow(, )
copy->  <double var>=StrictMath.pow(<double a>, <double b>);
Returns of 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 less than zero and the second argument is a finite even integer, then 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 first argument is less than zero and the second argument is a finite odd integer, then 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 first argument is finite and less than zero and 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 a fixed point of the method ceil or, which is the same thing, 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:
a - a double value.
b - a double value.
Returns:
the value ab.
static double random()
copy->  StrictMath.random()
copy->  <double var>=StrictMath.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.

Returns:
a pseudorandom double greater than or equal to 0.0 and less than 1.0.
See Also:
Random.nextDouble()
static double rint(double a)
copy->  StrictMath.rint( )
copy->  <double var>=StrictMath.rint(<double a>);
Returns the double value that is closest in value to a 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:
a - a double value.
Returns:
the closest double value to a that is equal to a mathematical integer.
static long round(double a)
copy->  StrictMath.round( )
copy->  <long var>=StrictMath.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:
a - a double value.
Returns:
the value of the argument rounded to the nearest long value.
See Also:
Long.MAX_VALUE, Long.MIN_VALUE
static int round(float a)
copy->  StrictMath.round( )
copy->  <int var>=StrictMath.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:
a - a float value.
Returns:
the value of the argument rounded to the nearest int value.
See Also:
Integer.MAX_VALUE, Integer.MIN_VALUE
static double sin(double a)
copy->  StrictMath.sin( )
copy->  <double var>=StrictMath.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 positive zero, then the result is positive zero; if the argument is negative zero, then the result is negative zero.
Parameters:
a - an angle, in radians.
Returns:
the sine of the argument.
static double sqrt(double a)
copy->  StrictMath.sqrt( )
copy->  <double var>=StrictMath.sqrt(<double a>);
Returns the 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 mathetmatical square root of the argument value.
Parameters:
a - a double value.
Returns:
the positive square root of a.
static double tan(double a)
copy->  StrictMath.tan( )
copy->  <double var>=StrictMath.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 positive zero, then the result is positive zero; if the argument is negative zero, then the result is negative zero
Parameters:
a - an angle, in radians.
Returns:
the tangent of the argument.
static double toDegrees(double angrad)
copy->  StrictMath.toDegrees( )
copy->  <double var>=StrictMath.toDegrees(<double angrad>);
Converts an angle measured in radians to the equivalent angle measured in degrees.
Parameters:
angrad - an angle, in radians
Returns:
the measurement of the angle angrad in degrees.
static double toRadians(double angdeg)
copy->  StrictMath.toRadians( )
copy->  <double var>=StrictMath.toRadians(<double angdeg>);
Converts an angle measured in degrees to the equivalent angle measured in radians.
Parameters:
angdeg - an angle, in degrees
Returns:
the measurement of the angle angdeg in radians.
 
Methods inherited from class java.lang.Object
clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait