Embedded Software and Motor Control Libraries for PXR40xx

Function GFLIB_Atan_FLT
4.32.5 Re-entrancy
The function is re-entrant.
4.32.6 Code Example
#include "gflib.h"
tFrac16 f16Input;
tFrac16 f16Angle;
void main(void)
{
// input ratio = 0x7FFF => 1
f16Input = FRAC16 (1);
}
// output angle should be 0x1FFF = 0.249999 => pi/4
f16Angle = GFLIB_Atan_F16 (f16Input, GFLIB_ATAN_DEFAULT_F16);
// output angle should be 0x1FFF = 0.249999 => pi/4
f16Angle = GFLIB_Atan (f16Input, GFLIB_ATAN_DEFAULT_F16, Define F16);
// ##############################################################
// Available only if 16-bit fractional implementation selected
// as default
// ##############################################################
// output angle should be 0x1FFF = 0.249999 => pi/4
f16Angle = GFLIB_Atan (f16Input);
4.33 Function GFLIB_Atan_FLT
This function implements rational polynomial approximation of arctangent function.
4.33.1 Declaration
tFloat GFLIB_Atan_FLT(tFloat fltIn, const GFLIB_ATAN_T_FLT *const pParam);
4.33.2 Arguments
Table 4-42. GFLIB_Atan_FLT arguments
Type Name Direction Description
tFloat fltIn input Input argument is a single precision floating point number
between (-2 128 , 2 128 ).
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Embedded Software and Motor Control Libraries for PXR40xx, Rev. 1.0
242 Freescale Semiconductor, Inc.