[R] Spectral analysis

[Gavin Simpson]

On Wed, 2007-06-06 at 13:55 -0700, David LEDU wrote:
> Hi all,
> 
> I am dealing with paleoceanographic data and I have a C14 time serie
> and one other variable. I would like to perform a spectral analysis
> (fft or wavelet) and plot it. Unfortunately I don't know the exact
> script to do this. Does anybody could send me an example to perform my
> spectral analysis ?
> 
> I Thank you
> 
> David

Invariably data of this nature are irregularly sampled in time, so you
should check whether the in-built spectrum() function is suitable for
your core data. I'm not aware of much else available in R, but one thing
I am aware of is a paper and R code by Mathias et al in the Journal of
Statistical Software:

http://www.jstatsoft.org/index.php?vol=11

It is issue 2 in that volume. This might be more suitable given your
data. The code is a few years old now and there isn't a ready built
package on CRAN so you'll have to compile it yourself.

HTH

G

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Gavin Simpson                     [t] +44 (0)20 7679 0522
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