How to use library to create a power spectrum

[Glowlink_Glowlink]

Hi,
I'm new to the Math Kernal Library.
Are there any examples that show how to to take a set to complex data and convert it to a power spectrum
thx

[ArturGuzik]

Hi,

I might be wrong but in MKL itself you'll need to use FFT routines and obtain it yourself. However, as far as I can remember, in IPP library there is PowerSpectr function which takes complex vector and computes its power spectrum in single call.

A.

[Gennady_F_Intel]

as usual Artur is right. :). Yes. Please see into IPP signal processing domain / Conversion Functions:

you can find such functions for double, float and short complex data types:

as an example

IppStatus ippsPowerSpectr_64fc(const Ipp64fc* pSrc, Ipp64f* pDst, int len);

where 64fc ( in IPP notation) == double complex ( MKL notation).

--Gennady

[Dmitry_B_Intel]

Hi,

Given the spectrum y=fft(x), power spectrum of x is ps=y*conj(y), the computation can be done with a simple loop readily vectorizable bycompiler, or with a call to MKL VML function, like this:
vcMulByConj(n,y,y,ps)

Thanks
Dima