[R] Stuck with FFT
seb.brockel at northampton.ac.uk
Mon Oct 27 19:01:57 CET 2008
Before I can get into serious Fourier analysis of Radon time-series I am
practising with 24hour and 24.8hour sinusoids to assist with my
interpretation of signals ittributed to tidal input to Radon time series.
I am stuck. I have tried researching this to no avail. I am awating a book
that should describe fourier transforms in detail and another one that
should discuss the R application.
I know what the command line is but I can't get it to refer to the array.
What is 'z'? If I have a table open entitled '24hsinusoids' with date/ time
column by the hour from January 01 2008 00:00 to January 02 2011 00:00
(X01.06.2008) (time column listed as X00:00) with corresponding sinudoidal
signal value column (X100) to give a complete curve for 24hours spread as
curves over the whole time-span, how can I fft from this table?
fft(z, inverse = FALSE) gives me as; object 'z' not found.
Please help and explain how R recognises the table and does fft's from it.
The time-series is discrete and periodic (or should be, as I need to analyse
my Radon time-series fro exactly this and I am very stuck now).
Thank you with all my heart if you can help.
View this message in context: http://www.nabble.com/Stuck-with-FFT-tp20192942p20192942.html
Sent from the R help mailing list archive at Nabble.com.
More information about the R-help