ILMathifftsym Method (InArraycomplex, NullableUInt32)

public static RetArray<double> ifftsym(
	InArray<complex> A,
	Nullable<uint> dim = null
)

Public Shared Function ifftsym ( 
	A As InArray(Of complex),
	Optional dim As Nullable(Of UInteger) = Nothing
) As RetArray(Of Double)

Dim A As InArray(Of complex)
Dim dim As Nullable(Of UInteger)
Dim returnValue As RetArray(Of Double)

returnValue = ILMath.ifftsym(A, dim)

Parameters

A

Type: ILNumericsInArraycomplex
Complex hermitian input array (frequency domain).

dim (Optional)

Type: SystemNullableUInt32
[Optional] The working dimension. Default: (null) first non-singleton dimension of A or dimension #0.

Return Value

Since a transform of complex hermitian input data results in an output having the imaginary part equal to zero, only the real part is returned for convenience reasons.

No check is made for A being hermitian! If A is not hermitian (by means of round-off errors), the result will be incorrect!

The forward fourier transform and the inverse fourier transform of a given data array A are mathematically equivalent. It's only a scaling factor which is needed to make sure, A equals ifft(fft(A)). That scaling is introduced in the inverse transform.

The transformation is computed by use of the native library which currently is set up for your processor and OS version. The underlying library is automatically choosen at ILNumerics startup and accessed via the static member ILMath.FFT. See the online documentation for more details in how to tune/configure and select dedicated native libraries. Currently supported libraries are: Intel MKL (included), AMD ACML and FFTW3 (prepared, optional modules, not included due to licensing conflicts).

[ILNumerics Computing Engine]

Reference