tpt_atan2_q15.c File Reference

#include "tpt_math.h"

Include dependency graph for tpt_atan2_q15.c:

Macros
#define	NORM_SH   (15)
#define	CST_1   (1L << NORM_SH)
#define	CST_2   (4L << NORM_SH)
#define	D2Q(F)
#define	MULQ(a, b)
#define	OCTANTIFY(_x, _y, _o)
#define	BRAD_PI   0x2000 /* 32768/4 */

Functions
static q31_t	atan1 (const q31_t x)
q15_t	tpt_atan2_q15 (q15_t y, q15_t x)
	Arc tangent in radian of y/x using sign of x and y to determine right quadrant.

Variables
static q15_t	ga []
static q15_t	gb []

Macro Definition Documentation

BRAD_PI

#define BRAD_PI   0x2000 /* 32768/4 */

CST_1

#define CST_1   (1L << NORM_SH)

CST_2

#define CST_2   (4L << NORM_SH)

D2Q

#define D2Q

(

F

)

Value:

((q15_t)((float)F * (float)CST_1))

MULQ

#define MULQ	(		a,
			b )

Value:

((q15_t)(((q31_t)(a) * (b)) >> 16))

NORM_SH

#define NORM_SH   (15)

OCTANTIFY

#define OCTANTIFY	(		_x,
			_y,
			_o )

Value:

  do                                                                           \
  {                                                                            \
    q31_t _t;                                                                  \
    _o = 0;                                                                    \
    if (_y < 0)                                                                \
    {                                                                          \
      _x = -_x;                                                                \
      _y = -_y;                                                                \
      _o -= 4;                                                                 \
    }                                                                          \
    if (_x <= 0)                                                               \
    {                                                                          \
      _t = _x;                                                                 \
      _x = _y;                                                                 \
      _y = -_t;                                                                \
      _o += 2;                                                                 \
    }                                                                          \
    if (_x <= _y)                                                              \
    {                                                                          \
      _t = _y - _x;                                                            \
      _x = _x + _y;                                                            \
      _y = _t;                                                                 \
      _o += 1;                                                                 \
    }                                                                          \
  } while (0);

Function Documentation

atan1()

q31_t atan1 ( const q31_t x )

inlinestatic

Variable Documentation

ga

q15_t ga[]

static

Initial value:

= {
    D2Q(0.00012894702004 / PI_F32), D2Q(0.00410552202930 / PI_F32),
    D2Q(0.01797827343558 / PI_F32), D2Q(0.04487866261926 / PI_F32),
    D2Q(0.08467202719892 / PI_F32), D2Q(0.13495471234832 / PI_F32),
    D2Q(0.19237801112651 / PI_F32), D2Q(0.25366425315298 / PI_F32)}

gb

q15_t gb[]

static

Initial value:

= {
    D2Q(0.99534894623805 / PI_F32 * 2), D2Q(0.96541373335686 / PI_F32 * 2),
    D2Q(0.91062230899554 / PI_F32 * 2), D2Q(0.83915654988516 / PI_F32 * 2),
    D2Q(0.75963586412685 / PI_F32 * 2), D2Q(0.67915650580081 / PI_F32 * 2),
    D2Q(0.60252898580173 / PI_F32 * 2), D2Q(0.53241718079412 / PI_F32 * 2)}