Computes an out-of-place radix-3 complex Fourier transform, either forward or inverse. The number of input and output values processed equals 3 times the power of 2 specified by parameter Log2N
; single precision.
SDKs
- iOS 4.0–9.0Deprecated
- macOS 10.2–10.11Deprecated
- Mac Catalyst 13.0–13.0Deprecated
- tvOS 9.0–9.0Deprecated
- watchOS 2.0–2.0Deprecated
Framework
- Accelerate
Declaration
void vDSP_fft3_zop(FFTSetup __Setup, const DSPSplit Complex *__A, v DSP _Stride __IA, const DSPSplit Complex *__C, v DSP _Stride __IC, v DSP _Length __Log2N, FFTDirection __Direction);
Parameters
__Setup
A setup object as returned by a call to
v
.DSP _create _fftsetup k
must be specified in the call toFFTRadix3 v
.DSP _create _fftsetup Setup
is preserved for reuse.__A
Complex input vector.
Note
The input data may be modified.
__IA
Stride between elements in
A
. The value ofIA
should be 1 for best performance.__C
Complex output vector.
__IC
Stride between elements in
C
. The value ofIC
should be 1 for best performance.__Log2N
The base 2 exponent of the number of elements to process in a single input signal.
Log2N
must be between 3 and 15, inclusive.__Direction
A forward/inverse directional flag, which must specify
k
(+1) orFFTDirection _Forward k
(-1)for an inverse transform.FFTDirection _Inverse
Discussion
This performs the following operation:

where F is Direction
, C is A
, j is the square root of -1
, and N is two raised to the power of Log2N
.
See also functions v
, v
, and vDSP Programming Guide.