У Срд, 09/03/2011 у 23:29 -0800, Dennis Murphy піша: > Hi: > > Here's one approach, although I imagine there are more efficient ways. > > # A function to strip spaces and return the first three non-blank elements > of a string > keyset <- function(x) substr(gsub(' ', '', x)[1], 1, 3)
Hello to everybody How to make a function which would find and cut off last free elements of a string (including blank elements)? Thank you in advance P.S. Chemotherapy studying pitfall (if someone would be interested). I've recently performed some crazy data transformations to study chemotherapy cycles. Million thanks to all who helped with advises in this mail-list (especially to Henrique Dallazuanna :)! So after help of [R] list my data were looked like id cycle1 cycle2 cycle3 cycle4 … cyclej 555 ac ac cmf ac NA After 'aggregate' approach I've got id regimen NUMcycles 555 ac->cmf 4->1 which is not true (but it turn out that it didn't really matter, because the majority were treated without such repeats in my study). This pitfall was not obvious for me (probably because of my ignorance) and maybe this hint will helpful for somebody who deals with similar stuff. However, after 'paste rle' approach I've got something like id regimen NUMcycles 555 ac->cmf->ac-> 2->1->1->20 where last number in 'NUMcycles' is the number of blanks (some patients received up to 24 cycles) That's why I am actually asking a question above Denis ______________________________________________ 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.