ACOS(3) | Library Functions Manual | ACOS(3) |
acos
— arc cosine
function
#include
<math.h>
double
acos
(double
x);
long double
acosl
(long
double x);
float
acosf
(float
x);
The
acos
()
function computes the principle value of the arc cosine of
x. The result is in the range [0, pi].
acos
(1) returns
+0.
acos
(x)
returns a NAN and raises the "invalid" floating-point exception
for |x| > 1.
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);
sin(3), cos(3), tan(3), asin(3), atan(3), atan2(3), sinh(3), cosh(3), tanh(3), math(3)
The acos
() function conforms to ISO/IEC
9899:2011.
December 11, 2006 | macOS 14.6 |