> -----Original Message----- > From: r-help-boun...@r-project.org > [mailto:r-help-boun...@r-project.org] On Behalf Of Martin D. Lepage > Sent: Thursday, September 24, 2009 7:38 AM > To: r-help@r-project.org > Subject: [R] Access to conditioning variables (lattice) > > [using R version 2.8.1 (2008-12-22)] > > Hello, > > I'm trying to access the conditioning variables of an xyplot within a > 'panel' function but I have not been able to figure out how to do so. > Here is a simple example that describes what I wish to do (the problem > lies with the commented line): > > dataset <- data.frame(x = c(1,2), y = c(4,5), Type = > factor(c("a","b"))) > xyplot( y ~ x | Type, dataset, > panel = function(...) { > panel.xyplot(...) > # do_something_with(conditioning_variables[which.packet()]) > }) > > The problem I am facing is that I do not know how to > generically access > the conditioning variables within the panel function. In this simple > case, I can achieve what I want to do with the following call : > > do_something_with(Type[which.packet()])
If your panel function has an argument called 'subscripts' then xyplot will pass it the row numbers of the data argument that correspond this the current panel. E.g., > xyplot( y ~ x | Type, dataset, + panel = function(..., subscripts) { + panel.xyplot(...) + cat("subscripts=", deparse(subscripts), ":\n") + print(dataset[subscripts,]) + }) subscripts= 1L : x y Type 1 1 4 a subscripts= 2L : x y Type 2 2 5 b You can use that information to add panel-specific information to the plot. Bill Dunlap TIBCO Software Inc - Spotfire Division wdunlap tibco.com > > but that requires the panel function call to have prior > knowledge of the > object used as the conditioning variable, which is not flexible enough > for my needs. > > Thank you, > Martin D. Lepage > > ______________________________________________ > 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.