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