Why do you need to use a data frame? A list will give you the flexibility you want:
d <- list( x=list( c(1,2), c(5,2), c(9,1) ), y=c( 1, -1, -1) ) Then you can access the individual elements > d$x [[1]] [1] 1 2 [[2]] [1] 5 2 [[3]] [1] 9 1 > d$y [1] 1 -1 -1 > d$x[[1]] [1] 1 2 -Christos > -----Original Message----- > From: [EMAIL PROTECTED] > [mailto:[EMAIL PROTECTED] On Behalf Of > Christian Convey > Sent: Monday, February 12, 2007 11:29 PM > To: r-help@stat.math.ethz.ch > Subject: [R] Can a data.frame column contain lists/arrays? > > I'd like to have a data.frame structured something like the following: > > d <- data.frame ( > x=list( c(1,2), c(5,2), c(9,1) ), > y=c( 1, -1, -1) > ) > > The reason is this: 'd' is the training data for a machine > learning algorithm. d$x is the independent data, and d$y is > the dependent data. > > In general my machine learning code will work where each > element of d$x is a vector of one or more real numbers. So > for instance, the same code should work when d$x[1] = 42, or > when d$x[1] = (42, 3, 5). > All that matters is that all element within d$x are > lists/vectors of the same length. > > Does anyone know if/how I can get a data.frame set up like that? > > Thanks, > Christian > > ______________________________________________ > 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 > and provide commented, minimal, self-contained, reproducible code. > > ______________________________________________ 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 and provide commented, minimal, self-contained, reproducible code.