[R] count occurrence and distance of characters in string

[Nordlund, Dan (DSHS/RDA)]

> -----Original Message-----
> From: r-help-bounces at r-project.org [mailto:r-help-bounces at r-
> project.org] On Behalf Of Immanuel
> Sent: Thursday, November 04, 2010 3:42 PM
> To: r-help at r-project.org
> Subject: [R] count occurrence and distance of characters in string
> 
> Hello all,
> 
> I want to know how often one character occurs in a given string
> and the distance from between every two occurences. (distance = other
> characters between them).
> 
> thanks
> 

Without a reproducible example, I can only guess.  But this should get you started.

s <- 'abcdeabcxdeabcdeaxabcdeabcdeabcdxeabc'
chr.pos <- which(unlist(strsplit(s,NULL)) == 'x')
chr.count <- length(chr.pos)
chr.dist <- diff(chr.pos)-1
chr.pos 
chr.count 
chr.dist

Hope this is helpful,

Dan

Daniel J. Nordlund
Washington State Department of Social and Health Services
Planning, Performance, and Accountability
Research and Data Analysis Division
Olympia, WA 98504-5204