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 -- %~%~%~%~%~%~%~%~%~%~%~%~%~%~%~%~%~%~%~%~%~%~%~%~%~%~%~%~%~%~%~%~%~%~%~% Gavin Simpson [t] +44 (0)20 7679 0522 ECRC [f] +44 (0)20 7679 0565 UCL Department of Geography Pearson Building [e] gavin.simpsonATNOSPAMucl.ac.uk Gower Street London, UK [w] http://www.ucl.ac.uk/~ucfagls/ WC1E 6BT [w] http://www.freshwaters.org.uk/ %~%~%~%~%~%~%~%~%~%~%~%~%~%~%~%~%~%~%~%~%~%~%~%~%~%~%~%~%~%~%~%~%~%~%~% ______________________________________________ R-help@stat.math.ethz.ch mailing list https://stat.ethz.ch/mailman/listinfo/r-help PLEASE do read the posting guide http://www.R-project.org/posting-guide.html and provide commented, minimal, self-contained, reproducible code.