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<math.h>: Mathematics

Detailed Description

 #include <math.h>

This header file declares basic mathematics constants and functions.

Note:
In order to access the functions delcared herein, it is usually also required to additionally link against the library libm.a. See also the related FAQ entry.


Defines

#define M_PI   3.141592653589793238462643
#define M_SQRT2   1.4142135623730950488016887

Functions

double cos (double __x) __ATTR_CONST__
double fabs (double __x) __ATTR_CONST__
double fmod (double __x, double __y) __ATTR_CONST__
double modf (double __value, double *__iptr)
double sin (double __x) __ATTR_CONST__
double sqrt (double __x) __ATTR_CONST__
double tan (double __x) __ATTR_CONST__
double floor (double __x) __ATTR_CONST__
double ceil (double __x) __ATTR_CONST__
double frexp (double __value, int *__exp)
double ldexp (double __x, int __exp) __ATTR_CONST__
double exp (double __x) __ATTR_CONST__
double cosh (double __x) __ATTR_CONST__
double sinh (double __x) __ATTR_CONST__
double tanh (double __x) __ATTR_CONST__
double acos (double __x) __ATTR_CONST__
double asin (double __x) __ATTR_CONST__
double atan (double __x) __ATTR_CONST__
double atan2 (double __y, double __x) __ATTR_CONST__
double log (double __x) __ATTR_CONST__
double log10 (double __x) __ATTR_CONST__
double pow (double __x, double __y) __ATTR_CONST__
int isnan (double __x) __ATTR_CONST__
int isinf (double __x) __ATTR_CONST__
double square (double __x) __ATTR_CONST__

Define Documentation

#define M_PI   3.141592653589793238462643
 

The constant pi.

#define M_SQRT2   1.4142135623730950488016887
 

The square root of 2.

Function Documentation

double acos (  double  __x  ) 
 

The acos() function computes the principal value of the arc cosine of x. The returned value is in the range [0, pi] radians. A domain error occurs for arguments not in the range [-1, +1].

double asin (  double  __x  ) 
 

The asin() function computes the principal value of the arc sine of x. The returned value is in the range [0, pi] radians. A domain error occurs for arguments not in the range [-1, +1].

double atan (  double  __x  ) 
 

The atan() function computes the principal value of the arc tangent of x. The returned value is in the range [0, pi] radians. A domain error occurs for arguments not in the range [-1, +1].

double atan2 (  double  __y,
double  __x
) 
 

The atan2() function computes the principal value of the arc tangent of y / x, using the signs of both arguments to determine the quadrant of the return value. The returned value is in the range [-pi, +pi] radians. If both x and y are zero, the global variable errno is set to EDOM.

double ceil (  double  __x  ) 
 

The ceil() function returns the smallest integral value greater than or equal to x, expressed as a floating-point number.

double cos (  double  __x  ) 
 

The cos() function returns the cosine of x, measured in radians.

double cosh (  double  __x  ) 
 

The cosh() function returns the hyperbolic cosine of x.

double exp (  double  __x  ) 
 

The exp() function returns the exponential value of x.

double fabs (  double  __x  ) 
 

The fabs() function computes the absolute value of a floating-point number x.

double floor (  double  __x  ) 
 

The floor() function returns the largest integral value less than or equal to x, expressed as a floating-point number.

double fmod (  double  __x,
double  __y
) 
 

The function fmod() returns the floating-point remainder of x / y.

double frexp (  double  __value,
int *  __exp
) 
 

The frexp() function breaks a floating-point number into a normalized fraction and an integral power of 2. It stores the integer in the int object pointed to by exp.

The frexp() function returns the value x, such that x is a double with magnitude in the interval [1/2, 1) or zero, and value equals x times 2 raised to the power *exp. If value is zero, both parts of the result are zero.

int isinf (  double  __x  ) 
 

The function isinf() returns 1 if the argument x is either positive or negative infinity, otherwise 0.

int isnan (  double  __x  ) 
 

The function isnan() returns 1 if the argument x represents a "not-a-number" (NaN) object, otherwise 0.

double ldexp (  double  __x,
int  __exp
) 
 

The ldexp() function multiplies a floating-point number by an integral power of 2.

The ldexp() function returns the value of x times 2 raised to the power exp.

If the resultant value would cause an overflow, the global variable errno is set to ERANGE, and the value NaN is returned.

double log (  double  __x  ) 
 

The log() function returns the natural logarithm of argument x.

If the argument is less than or equal 0, a domain error will occur.

double log10 (  double  __x  ) 
 

The log10() function returns the logarithm of argument x to base 10.

If the argument is less than or equal 0, a domain error will occur.

double modf (  double  __value,
double *  __iptr
) 
 

The modf() function breaks the argument value into integral and fractional parts, each of which has the same sign as the argument. It stores the integral part as a double in the object pointed to by iptr.

The modf() function returns the signed fractional part of value.

double pow (  double  __x,
double  __y
) 
 

The function pow() returns the value of x to the exponent y.

double sin (  double  __x  ) 
 

The sin() function returns the sine of x, measured in radians.

double sinh (  double  __x  ) 
 

The sinh() function returns the hyperbolic sine of x.

double sqrt (  double  __x  ) 
 

The sqrt() function returns the non-negative square root of x.

double square (  double  __x  ) 
 

The function square() returns x * x.

Note:
This function does not belong to the C standard definition.

double tan (  double  __x  ) 
 

The tan() function returns the tangent of x, measured in radians.

double tanh (  double  __x  ) 
 

The tanh() function returns the hyperbolic tangent of x.

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