mirror of
https://github.com/autc04/Retro68.git
synced 2024-11-24 07:31:32 +00:00
46 lines
857 B
C
46 lines
857 B
C
|
|
/* @(#)z_atanf.c 1.0 98/08/13 */
|
|
/******************************************************************
|
|
* Arctangent
|
|
*
|
|
* Input:
|
|
* x - floating point value
|
|
*
|
|
* Output:
|
|
* arctan of x
|
|
*
|
|
* Description:
|
|
* This routine returns the arctan of x.
|
|
*
|
|
*****************************************************************/
|
|
|
|
#include "fdlibm.h"
|
|
#include "zmath.h"
|
|
|
|
float
|
|
_DEFUN (atanf, (float),
|
|
float x)
|
|
{
|
|
switch (numtestf (x))
|
|
{
|
|
case NAN:
|
|
errno = EDOM;
|
|
return (x);
|
|
case INF:
|
|
/* this should check to see if neg NaN or pos NaN... */
|
|
return (__PI_OVER_TWO);
|
|
case 0:
|
|
return (0.0);
|
|
default:
|
|
return (atangentf (x, 0, 0, 0));
|
|
}
|
|
}
|
|
|
|
#ifdef _DOUBLE_IS_32BITS
|
|
double atan (double x)
|
|
{
|
|
return (double) atangentf ((float) x, 0, 0, 0);
|
|
}
|
|
|
|
#endif /* defined(_DOUBLE_IS_32BITS) */
|