[R] adding group totals to a table

[Anders Schwartz Corr]

Hi Chris, This is a very rough first conceptual program you could use -- 
double check all the syntax as I know it won't work at first go. It's 
untested but can be jiggered to work! Good luck! Anders

Use unique() to get your unique combinations, then loop or vectorize 
through each unique combination to count the combos.

unique(data)->x
thirdcol<-NULL
for(i in 1:dim(data)[1]){
 	for(k in 1:dim(x)[1]{
 	thirdcol<-cbind(thirdcol,dim(data[data[i,] %in% x[k,]])[1])
}}

newdata<-cbind(data,thirdcol)

On Sun, 9 Dec 2007, christopher snow wrote:

> I have a table with two columns:
>
> A   1
> A   1
> A   2
> B   2
> C   0
>
> I would like to produce a third column that contains the counts of each
> unique combination of col1 and col2:
>
> A   1  2
> A   1  2
> A   2  1
> B   2  1
> C   0  1
>
> How can I do this in R?
>
> Thanks in advance ...
>
>
> -- 
> This message has been scanned for viruses and
> dangerous content by MailScanner, and is
> believed to be clean.
>
> ______________________________________________
> R-help at 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.
>