Creates a double-precision Hanning window.
SDKs
- iOS 4.0+
- macOS 10.4+
- Mac Catalyst 13.0+Beta
- tvOS 9.0+
- watchOS 2.0+
Framework
- Accelerate
Declaration
func vDSP_hann_windowD(_ __C: UnsafeParameters
__CDouble-precision real output vector.
__NThe desired window length.
__FlagThe
Flagparameter can have the following values:vcreates a denormalized window.DSP _HANN _DENORM v|DSP _HANN _DENORM vcreates a denormalized window with only the first (N+1)/2 points.DSP _HALF _WINDOW vcreates a normalized window.DSP _HANN _NORM v|DSP _HANN _NORM vcreates a normalized window with only the first (N+1)/2 points.DSP _HALF _WINDOW
Discussion
The v and v functions create a Hanning window vector, and write the result to C, which can be multiplied by a vector using v.
If Flag & vDSP_HANN_NORM:
W = .8165;
Else
W = .5;
for (n = 0; n < Length; ++n)
C[n] = W * (1 - cos(2*pi*n/N));
The following code shows how to generate a Hann window.
let n = vDSP_Length(1024)
var c = [Float](repeating: 0,
count: Int(n))
vDSP_hann_window(&c,
n,
Int32(vDSP_HANN_DENORM))
The following illustrates the values of the output vector, c:
