I have started putting my various PD functions together in an R package (PDcalc). You can find a development version of the package here:
I will keep all current versions of the functions available for download from this site for as long as I can but they will not be updated. All future development will be for the R package.
Thanks to everyone who has been using (and providing feedback on) my functions. I hope you find PDcalc as least as useful.