[R] indexing via a character matrix?

From: Roger Levy <rlevy_at_inf.ed.ac.uk>
Date: Tue 14 Feb 2006 - 05:29:03 EST


Is it possible to index via a character matrix? For example, I would like to do the following:

cont.table <- table(df1$A,df1$B) # df1 a data frame with factors A and B cont.table[cbind(df2$A,df2$B)] # df2 a smaller data frame with some

                                  # pairings of values for A and B

but the second step does not work -- I guess that matrices to be used for indexing this way must be numeric. Is there a way to index multiple character tuples out of a contingency table without resorting to writing loops?

Many thanks,

Roger Levy

R-help@stat.math.ethz.ch mailing list
https://stat.ethz.ch/mailman/listinfo/r-help PLEASE do read the posting guide! http://www.R-project.org/posting-guide.html Received on Tue Feb 14 05:38:46 2006

This archive was generated by hypermail 2.1.8 : Fri 03 Mar 2006 - 03:42:29 EST