[R] Counting the occurences of a charater within a string

Hadley Wickham hadley at rice.edu
Sat Dec 3 20:10:04 CET 2011


On Thu, Dec 1, 2011 at 10:32 AM, Douglas Esneault
<Douglas.Esneault at mecglobal.com> wrote:
> I am new to R but am experienced SAS user and I was hoping to get some help on counting the occurrences of a character within a string at a row level.
>
> My dataframe, x,  is structured as below:
>
> Col1
> abc/def
> ghi/jkl/mno
>
> I found this code on the board but it counts all occurrences of "/" in the dataframe.
>
> chr.pos <- which(unlist(strsplit(x,NULL))=='/')
> chr.count <- length(chr.pos)
> chr.count
> [1] 3
>
> I'd like to append a column, say cnt, that has the count of "/" for each row.

Here's an easy way from stringr:

library(stringr)
str_count( c("abc/def", "ghi/jkl/mno"), "/")
# [1] 1 2

Hadley

-- 
Assistant Professor / Dobelman Family Junior Chair
Department of Statistics / Rice University
http://had.co.nz/



More information about the R-help mailing list