Hi all, I'm trying to write a function that will search and extract from a long character string, but with a twist: I want to use the characters before and the characters after what I want to extract as reference points. For example, say I'm working with data entries that looks like this:
Drink=Coffee:Location=Office:Time=Morning:Market=Flat Drink=Water:Location=Office:Time=Afternoon:Market=Up Drink=Water:Location=Gym:Time=Evening:Market=Closed Drink=Wine:Location=Restaurant:Time=LateEvening:Market=Closed ... For my function, I'd like to find what's located between "Location=", and ":Time=" in every instance, and extract it, to return something like "Office, Office, Gym, Restaurant". In a previous discussion I found (http://tolstoy.newcastle.edu.au/R/help/05/03/0344.html), someone wrote a function where you could find and substitute characters in a string, based on "pre" and "post" variables: interp <- function(x, e = parent.frame(), pre = "\\$", post = "" ) { for(el in ls(e)) { tag <- paste(pre, el, post, sep = "") if (length(grep(tag, x))) x <- gsub(tag, eval(parse(text = el), e), x) } x } I'm not sure how to modify it, however, to do what I want it to do. Any suggestions? Thanks in advance, Andrew -- View this message in context: http://r.789695.n4.nabble.com/Search-and-extract-string-function-tp2290268p2290268.html Sent from the R help mailing list archive at Nabble.com. ______________________________________________ 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.
