Here is one approach: (Some steps are intermediary steps to illustrate what is going on)
#create sample strings #repeat each of them 10 times string=rep(c( "Lorem ipsum dolor sit amet", "Lorem ipsum, and lorem ipsum something else", "Foo", "Bar", "Foobar"),10) ##Create a gender variable gender=rep(0:1,each=25) ##Create an index variable index=1:length(string) ##This is the string you want to look for i.am.looking.for="Lorem ipsum" ##Return the indices of the strings ##in which "lorem ipsum" is found? grep(i.am.looking.for,string) ##Return a boolean for each index ##whether "lorem ipsum" is found or not? index%in%grep(i.am.looking.for,string) ##Finally, table the occurrence/absence of ##"lorem ipsum" by gender table(index%in%grep(i.am.looking.for,string),gender) Hope that helps, Daniel ------------------------- cuncta stricte discussurus ------------------------- -----Ursprüngliche Nachricht----- Von: r-help-boun...@r-project.org [mailto:r-help-boun...@r-project.org] Im Auftrag von w_poet Gesendet: Sunday, September 20, 2009 11:58 AM An: r-help@r-project.org Betreff: [R] how to count occurrences of string? Hi everyone, I have an array with a variable called comments. I wish to count the number of subjects whose post-experiment comments contain a string x and then cross tab this with other variables of interest, ex. age. Does anyone have any suggestions on how to count unique occurrences of a string embedded within a variable and cross-tab it with other variables? I've looked through the help files, etc. One method I tried was to use strsplit to split comments. I can use this with table to count the number of occurrences of x, but I can't cross tab this with other variables because comments is a ragged array after being split. Thanks in advance, Stephen -- View this message in context: http://www.nabble.com/how-to-count-occurrences-of-string--tp25530083p2553008 3.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. ______________________________________________ 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.
