Hello R users, I have successfully created a square (or more generally, rectangular) tophat smoothing routine based on altering the already available KDE2D. I would be keen to implement a circular tophat routine also, however this appears to be much more difficult to write efficiently (I have a routine, but it's very slow). I tried to create one based on using crossdist to create a distance matrix between my data and the sampling grid, but it doesn't take a particularly large amount of data (or hi res grid) for memory to be a big problem. The 2D density routines I have been able to find either don't support a simple tophat, or don't use the absolute distances between the sampling grid and the data. Should anyone know of more general 2D density routines that might support circular tophats, or know of a simple and efficient method for creating them, I would be very grateful.
Aaron [[alternative HTML version deleted]] ______________________________________________ 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.