ACOS(3) BSD Library Functions Manual ACOS(3)NAME
acos, acosf, acosl -- arc cosine functions
LIBRARY
Math Library (libm, -lm)
SYNOPSIS
#include <math.h>
double
acos(double x);
float
acosf(float x);
long double
acosl(long double x);
DESCRIPTION
The acos(), acosf(), and acosl() functions compute the principal value of the arc cosine of x.
RETURN VALUES
These functions return the arc cosine in the range [0, pi] radians. If:
|x| > 1,
acos(x) raises an invalid exception and returns an NaN.
SEE ALSO asin(3), atan(3), atan2(3), cos(3), cosh(3), fenv(3), math(3), sin(3), sinh(3), tan(3), tanh(3)STANDARDS
The acos(), acosf(), and acosl() functions conform to ISO/IEC 9899:1999 (``ISO C99'').
BSD July 31, 2008 BSD
Check Out this Related Man Page
ACOS(3) BSD Library Functions Manual ACOS(3)NAME
acos -- arc cosine function
SYNOPSIS
#include <math.h>
double
acos(double x);
long double
acosl(long double x);
float
acosf(float x);
DESCRIPTION
The acos() function computes the principle value of the arc cosine of x. The result is in the range [0, pi].
SPECIAL VALUES acos(1) returns +0.
acos(x) returns a NAN and raises the "invalid" floating-point exception for |x| > 1.
VECTOR OPERATIONS
If you need to apply the acos() function to SIMD vectors or arrays, using the following functions provided by the Accelerate.framework may
give significantly better performance:
#include <Accelerate/Accelerate.h>
vFloat vacosf(vFloat x);
void vvacosf(float *y, const float *x, const int *n);
void vvacos(double *y, const double *x, const int *n);
SEE ALSO sin(3), cos(3), tan(3), asin(3), atan(3), atan2(3), sinh(3), cosh(3), tanh(3), math(3)STANDARDS
The acos() function conforms to ISO/IEC 9899:2011.
BSD December 11, 2006 BSD
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