as.character() will enable me to do this in a loop (so thanks!). It looks like you guys are suggesting I accomplish this in some kind of vectorized fashion (David: yes, the number of rows are not equal - and I need to compare ALL pairs, not just adjacent pairs, so to vectorize, I suppose I'd have to use the dyadic(?).
But I have a rather complicated conditional, so if my dataframes were huge or I had to do this many, many times, I would think about how to vectorize this, but in my case, just running through in a loop suits my needs. Thanks! Jonathan On Thu, May 5, 2011 at 6:39 PM, Ista Zahn <iz...@psych.rochester.edu> wrote: > Hi Jonathan, > > On Thu, May 5, 2011 at 6:28 PM, J <jonsle...@gmail.com> wrote: > > Hi, I'm requesting you don't berate me for asking this question: > > > > I clearly don't have the gist of factors. > > > > I have two dataframes, A and B. > > > > Each of them has a column containing strings (they're labels). > > > > I want to, one-by-one in a loop, compare the particular string in an > entry from dataframe A to an entry in B, to see if they're the same. > > This is probably not the best way. Much easier to compare them all in one > go. > > > > > The problem, when posing the question: > > searchID1 <- A[['label']][i] > > possMatch1 <- B[['label']][j] > > searchID1 == possMatch1 > > > > I get the error: > > Error in Ops.factor(searchID1, possMatch1) : > > level sets of factors are different > > > > I presume this is because the set of possible values in the 'labels' > columns, respectively in A and B, differ. In my case, I'm not interested in > this at all; I just want to compare individual entries from the two > dataframes in a pair-wise fashion. > > > > Can I strip the "factors" associated with the entries? Is there a better > way? > > Yes, you can "strip the factors" using as.character(). Alternatively, > you could use set the factor levels using factor() or levels. Either > way, I would just do > > A$label == B$label > > Instead of a loop. > > Best, > Ista > > > > Jonathan > > > > > > [[alternative HTML version deleted]] > > > > ______________________________________________ > > 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. > > > > > > -- > Ista Zahn > Graduate student > University of Rochester > Department of Clinical and Social Psychology > http://yourpsyche.org > [[alternative HTML version deleted]] ______________________________________________ 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.
