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From: "Steve Conahan" <sconahan@mathworks.com>
Newsgroups: comp.dsp,comp.soft-sys.matlab
Subject: Re: DFT of an irregular time-spacing signal
Date: Tue, 22 Oct 2002 10:55:49 -0400
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Hi CCC,

If the other suggested alternatives do not help you (such as first
interpolating the data to make it uniformly spaced before using the DFT
function), then you may need to write your own MATLAB function to compute
the DFT at only the irregularly-spaced points that you are interested in.
Basically, you would need to find a definition of DFT in a textbook and
implement it directly as a function in M.

In addition, I will let me colleagues here know about this need for a new
DFT function for irregularly-spaced data.

Thanks,
Steve
The MathWorks

"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?
>
> Thanks.
> CCC
>
>
>