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From: heath@ll.mit.edu (Greg Heath)
Newsgroups: comp.dsp,comp.soft-sys.matlab
Subject: Re: DFT of an irregular time-spacing signal
Date: 22 Oct 2002 17:11:09 -0700
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"Chia C Chong" <Chia.Chong@ee.ed.ac.uk> wrote in message news:<ap23dq$94e$1@scotsman.ed.ac.uk>...
> Hi Greg,
> 
> It seems like no such a function in Matlab(dft)??

Sorry Chia,

The dft.m on our local network was written by a former employee.
The code looks like a straightforward implementation of the equations 
given in "help fft".

There are dft algorithms around (in Fortran I think) that are fast. 
I have a list somewhere that I got from a recent google search.
I think it led me to some old newsgroup posts on either comp.dsp or 
sci.math.num-analysis.

I will relay the info if I can find it(my office mate got tired of my
mess and "reorganized" the office).

I think I used the word "nonequidistant" as a search keyword.

Hope this helps.

Greg

> "Greg Heath" <heath@ll.mit.edu> wrote in message
> news:9e910d7a.0210211421.4fcf9eb@posting.google.com...
> > "Chia C Chong" <Chia.Chong@ee.ed.ac.uk> wrote in message
>  news:<ap102a$6ce$1@scotsman.ed.ac.uk>...
> > > Hi there!
> > >
> > > I have a signal, y which has irregular time-spacing. I would like to
>  find
> > > the power spectrum of this signal. Since the signal has irregular
> > > time-spacing, I guess I can't simply perform the DFT using the fft
>  command
> > > in Matlab?? If so, what method should I used in order to find the power
> > > spectrum of y?
> >
> > help dft