Re: fourier ( FFT )
- To: mathgroup at smc.vnet.net
- Subject: [mg52103] Re: [mg52077] fourier ( FFT )
- From: yehuda ben-shimol <benshimo at bgu.ac.il>
- Date: Thu, 11 Nov 2004 04:52:02 -0500 (EST)
- References: <200411100945.EAA11193@smc.vnet.net>
- Sender: owner-wri-mathgroup at wolfram.com
I assume the followings:
1) you already have a list of pairs such as
myData={{x1,f[x1]},{x2,f[x2]},...}
2) x2-x1=x3-x2=..., that is, equal spaced samples.
under this all you need to do is to take the last value of each pair and
use Fourier
Fourier[Last /@ myData]
will do the trick.
yehuda
bar at ANTYSPAM.ap.krakow.pl wrote:
>Hi
>
>My file has form:
>x1 f(x1)
>x2 f(x2) ....
>
>How can I use Mathematica to obtain frequencies ?
>
>Fourier[] works on only one list!
>
>When i tested with f(x)=Sin[a x] sometimes
>i obtained wrong result.
>
>
>regards, Olaf
>
>
>
- References:
- fourier ( FFT )
- From: bar@ANTYSPAM.ap.krakow.pl
- fourier ( FFT )