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From: Greg Heath <heath@alumni.brown.edu>
Newsgroups: comp.soft-sys.matlab
Subject: Re: time and frequency domain
Date: Sun, 11 May 2008 05:30:42 -0700 (PDT)
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Corrected for the unforgivable sin of TOP-POSTING!

On May 11, 7:00=A0am, "Chen Sagiv" <chensagiv...@gmail.com> wrote:
> Greg Heath <he...@alumni.brown.edu> wrote in message
>
> <3c59d7c3-618b-44c2-816a-
> b58be9319...@24g2000hsh.googlegroups.com>...
>
> > On May 10, 3:58=3DA0pm, "Chen Sagiv"
> <chensagiv...@gmail.com> wrote:
> > > Hi,
>
> > > It is not important when you plot the abs of the FT, but
> > > shouldn't you use instead:
>
> > > > f1 =3D3D zeros(1,512);
> > > > f1(128:383) =3D3D hamming(256);
>
> > > > f2 =3D3D zeros(1,512);
> > > > f2(128:383) =3D3D 1;
>
> > > > fft_f1 =3D3D fftshift(fft(ifftshift(f1),2048));
> > > > fft_f2 =3D3D fftshift(fft(ifftshift(f2),2048));
>
> > Absolutely not!
>
> > Hope this helps.

> Hi Greg,
>
> No, it doesn't help. Can you explain your very short
> response ?

There is no point to using ifftshift.

When I ran your code the spectra exhibted hashy
artifacts.

Did you cut what you wrote,  paste it into a command
 line, and compare the plots with the originals??

The results are obviously incorrect.

Hope this helps.

Greg