[R] Q about strsplit and regexp

Liaw, Andy andy_liaw at merck.com
Wed Oct 20 14:15:40 CEST 2004

Dear R-help,

This one is probably a piece of cake for regexp masters.  I'd like to split
a character vector (for simplicity, say of length one for now) that contains
fields that are delimited by arbitrary number of white spaces (e.g., "  a b
c ").  How do I get the character vector that contain the fields?  In the
example I gave, I've tried:

> strsplit("  a b    c ", " +")
[1] ""  "a" "b" "c"

I do not want that empty character in the beginning, but couldn't figure out
how to strip the starting white spaces, other than something ugly like:

> strsplit(sub("^ +", "", "  a b    c "), " +")
[1] "a" "b" "c"

Can some kind soul point me to a simpler way?  TIA!!


Andy Liaw, PhD
Biometrics Research      PO Box 2000, RY33-300     
Merck Research Labs           Rahway, NJ 07065
andy_liaw <at> merck.com          732-594-0820

More information about the R-help mailing list