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From:  Srikanth <skt@xdtech.com>
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: Wed, 27 Jun 2007 07:09:13 -0000
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when you say you want to zoom in on certain parts of f(t), what do you
mean? The data is already in form of samples, you really can't get new
data, since all the information is already in the samples. For example
if your samples represent the signal at T,2T etc, there is no way you
can exactly know what happened at 1.5 T - that data is lost. For your
application, the easiest way would be to display every 10th sample,
for example, to start with. Then, if the user selects a region,
display every 5th sample in that region. If he zooms in further,
display every sample. If he goes closer than this, you need to do some
interpolation.