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From: "Mike" <meatheadIV@gmail.com>
Newsgroups: comp.soft-sys.matlab,comp.dsp
Subject: DFT the same as sampled Foureir transform?
Date: Thu, 24 May 2007 00:45:45 -0700
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Hi all,

I have the following question regarding the relation between DFT and Foureir 
Transform.

Suppose I have a sequence of discrete time signal x0, x1, x2, ... xn, ... 
(possibly infinite length), uniformly spaced in time, with spacing T; that's 
to say, x0 is the signal value at time 0, x1 is the signal value at time 
1*T, x2 is the signal value at time 2*T, ...

and the DFT of this sequence is F1(v).

Also, for this sequence of signal, I have an ordinary Foureir Transform 
F2(v), I guess it's called DTFT.

I plan to sample the F2(v) to obtain the discrete version of the F2(v) and 
call it F3(v).

My question is:

Under what condition and for what kind of signal x's do the DFT F1(v) and 
sampled version of ordinary FT F3(v) equate? I want F1(v) and F3(v) to be 
exactly the same... what conditions shall I impose?

Thanks!