Paul Kienzle wrote: > > On Jan 9, 2009, at 6:12 PM, Ryan May wrote: > >> Maybe it's time to refactor here to get routine(s) that operate how we >> want (IMO >> more sanely than Matlab), and we provide wrappers that give >> Matlab-like behavior. >> Maybe we can also get these sane routines upstream into Scipy. At >> that point, >> however, I'm not sure what to do about the plotting functions, since >> there's a >> variety of behavior. > > My policy when working on Octave was to avoid inventing new interfaces > when the existing interfaces are good enough. This doesn't apply to the > same degree in pylab of course because there is little hope of running > matlab code directly off the net, but it still helps users if things > with the same name share the same interface. It would not be good if > importing psd from the matlab compatibility package gave a different > interface than the same function name imported directly from mpl or scipy.
I agree 100%. My thoughts were having a flexible, yet simple and straightforward implementation in scipy/matplotlib, and reimplement psd() on top of that. I don't think psd is a good name anyways, since it is specifically based on the welch method. While general, this is only 1 way of estimating the psd of the signal. > In terms of refactoring, consider having a spectral density object. The > following properties of psd naturally lends itself to an object interface: > > * a number of related functions (psd, csd, transfer function, > coherence) can be calculated from the same internal state > * the state can be fed new inputs and updated frame by frame, > * confidence intervals may or may not be requested, > * data can be plotted in multiple ways > * users may want to extract the data for further processing > > It would be pretty easy to build the matlab interface on top of such an > object. I hadn't thought of an OO interface, but that's not usually my primary way of thinking. It actually sounds like a good way to go, and is, in fact, the way MatLab has gone now. It would also allow making a class hierarchy that uses different methods for doing these calculation (plain periodogram, welch's method, etc.). Some food for thought anyways. Ryan -- Ryan May Graduate Research Assistant School of Meteorology University of Oklahoma ------------------------------------------------------------------------------ This SF.net email is sponsored by: SourcForge Community SourceForge wants to tell your story. http://p.sf.net/sfu/sf-spreadtheword _______________________________________________ Matplotlib-devel mailing list Matplotlib-devel@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/matplotlib-devel
