On Fri, Feb 17, 2012 at 11:06:23PM +0300, Naser Albalwi wrote: > > Thank, thats what I need, using> the built-in help system and R's capability > to allow you to view source code for functions, but how???
Hi. First, type "cov" without quotation marks to R's prompt. The printed code calls .Internal(cov(...)), which means that the main part is done in C code. Then, it is probably the best to download R sources and unpack. The code for cov() is in the file R/src/main/cov.c. The call goes first to function do_cov(). Then you have to search a bit. The main part is computed in one of the functions cov_pairwise1(), cov_pairwise2(), cov_complete1(), or cov_complete2(). Probably, other members of the list may correct me, if this is not correct. Basic formulas for the covariance are at Wikipedia http://en.wikipedia.org/wiki/Covariance Hope this helps. Petr Savicky. ______________________________________________ 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.
