1.4.3.19 _LIBQ_Q2_29_atan_Q16 Function

Calculates the value of atan(x).

Description

_Q2_29 _LIBQ_Q2_29_atan_Q16 (_Q16 x);

Calculates the atan(x), where x is of type _Q16 and the resulting value is of type _Q2_29. The output value will be radians in the range pi >= result >= -pi.

Preconditions

None.

Parameters

x The _Q16 input value from which to calculate atan(x).

Returns

_LIBQ_Q2_29_atan_Q16 returns the _Q2_29 fixed point result from the calculation atan(x).

Remarks

The function _LIBQ_Q2_29_atan2_Q16 is called by this routine and thus must be linked into the executable image.

Execution Time (cycles): 354 typical (178 to 360)

Program Memory 16 bytes

Error <= 0.000000003 (accurate within one least significant _Q2_29 bit)

Example

_Q2_29 resultAtan;

resultAtan = _LIBQ_Q2_29_atan_Q16 ((_Q16)0x00098b31); 

_// _LIBQ_Q2_29_atan_Q16(9.543716) =_ _1.466396 (0x2eecb7ee)_

C

_Q2_29 _LIBQ_Q2_29_atan_Q16 (_Q16 x );