Zitat von Duncan Murdoch <[EMAIL PROTECTED]>: > Oliver Bandel wrote: > > Hello, > > > > > > I'm new to R (using it since about two weeks), > > but absolutely a fan of it from the beginning on. :-) > > > > Best tool for working with data I found. :-) > > > > I tried using the fft() and other funcitons for > > analysing time series. > > > > What I would be glad to have, would be a > > convenient way to display the complex result > > of a fft in a way, that real and imaginary parts > > each use an axis for themselves, and the index of the > > resulting values use the third axe. > > > > When displaying this as a 3D->2D picture, > > it also would be nice, to change the view, > > like it can be done with persp(). > > > > Is there already a package or script for preparing the data > > of an fft to be displayed in this way? > > I don't find this very enlightening, but here you go: > > x <- rnorm(1000) > f <- fft(x) > > library(rgl) > plot3d(1:length(f), Re(f), Im(f)) [...]
Ok, this is a starting point. :-) It would be enlightening, if you have a timeseries that is not noise only, and if the plot would not use dots. So, using a timeseries that is derived from some data could be very interesting. But rnorm creates noise only, and not a deterministic signal. So the resulting fft values look quite boring ;-) Instead of dots, a line from the index-axis at Re=0, Im=0 to the value of the fft at that index should be drawn. BTW: how to change the perspective? I did not found an angle-parameter for the plot3d()-function. Ciao, Oliver ______________________________________________ R-help@r-project.org 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.
