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From: Greg <heath@alumni.brown.edu>
Newsgroups: comp.soft-sys.matlab
Subject: Re: FFT
Date: Sat, 4 Jul 2009 12:10:26 -0700 (PDT)
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On Jul 1, 2:02 am, "guj " <gulatiaks...@gmail.com> wrote:
> I was doing an experiment, and find thatFFTand NDFT are giving little different results when i implement it on uniform sampled sin signal with 101 samples.
>
> Although results are same. Only difference is the some noise near the spike. Noise is zero in case of NDFT but little noise can be seen inFFT Should i expect the same results from both of them

Since floating point calculations are used, you will have to
quantify
your statement. What is the normalized mean-squared error

mean(abs(X2-X1).^2)/mean(abs(X1-mean(X1)))

Hope this helps.

Greg

> Any comments will be appreciated. I have some images for what i have done, if some body interested in seeing. Drop me a  mail at pinkfloydin...@yahoo.com

If your error is sisnificant and I have some time, I will look at it.