matching period with perl regular expression
On 13-May-09 23:47:41, Henrique Dallazuanna wrote:
Try this:
gsub("^(\\w*).*$", "\\1", x)
Even simpler:
x
# [1] "wa.w"
gsub("\\..*","",x,perl=TRUE)
# [1] "wa"
x<-"abcde.fghij.klmno"
gsub("\\..*","",x,perl=TRUE)
# [1] "abcde"
(and it doesn't matter whether 'perl' is TRUE or FALSE)
Ted.
On Wed, May 13, 2009 at 8:41 PM, Stephen J. Barr <stephenjbarr at gmail.com>wrote:
Hello, I have several strings where I am trying to eliminate the period and everything after the period, using a regular expression. However, I am having trouble getting this to work.
x = "wa.w" gsub(x, "\..*", "", perl=TRUE)
[1] "" Warning messages: 1: '\.' is an unrecognized escape in a character string 2: unrecognized escape removed from "\..*" In perl, you can match a single period with \. Is this not so even with perl=TRUE. I would like for x to be equal to
x = "wa"
What am I missing here? -stephen ========================================== Stephen J. Barr University of Washington WEB: www.econsteve.com
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--
Henrique Dallazuanna
Curitiba-Paran?-Brasil
25? 25' 40" S 49? 16' 22" O
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