Dear all, I am having some difficulties understanding how the .combine option in the foreach function of the "foreach" package works.
I think I understand the examples in the manual using rbind, cbind and c. However if I write my own function (no particular purpose in mind, just to figure out how the .combine option works): cfun <- function(a,b) sqrt(a**2 + b**2) I don't understand the output of the function: For example : x <- foreach(i=1:3, .combine='cfun') %do% seq(5) Produces: > x [1] 1.732051 3.464102 5.196152 6.928203 8.660254 Now so far as I understand these are in order: sqrt(1+1+1), sqrt(4 + 4 + 4) [ = sqrt(2**2 + 2**2 + 2**2) ], sqrt(27) [ = sqrt(3**2 + 3**2 + 3**2)] and so on... But really I don't understand how cfun is used to produced these results, what is passed to a and b in this case??? Thanks a lot you all, Cheers, Luca ______________________________________________ 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.
