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From:  Benj <bjacoby@iwaynet.net>
Newsgroups: comp.soft-sys.matlab,sci.math.num-analysis,comp.dsp,sci.math,sci.physics
Subject: Re: How to zoom into a certain part of FFT?
Date: Tue, 26 Jun 2007 23:57:41 -0700
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Vista wrote:
> Hi all,
>
> Suppose I have a signal f(t), t is in [0, +infinity).

> Which part of f(t) does this inverse FFT f_hat represent?

The part with frequencies inside the bandpass you selected.

> If I want to zoom into a certain part of f(t), how can I use inverse FFT to
> do that?

If you want to zoom in on f(t), did you ever think of just zooming in
on f(t)?
No FT required! Duh!

Methinks you have no idea what you are doing.