You can use names insteed: DF <- data.frame(a=1:3, b=2:4) lapply(names(DF), function(x){ print(x) DF[x] })
On Mon, Sep 28, 2009 at 8:22 AM, Heinz Tuechler <tuech...@gmx.at> wrote: > Dear All, > > to produce output of several columns of a data frame, I tried to use lapply > and also l_ply. In both cases, I would like to print a header line > containing also the name of the respective column in the data frame. > > For example, I would like the following > > lapply(data.frame(a=1:3, b=2:4), function(x) print(deparse(substitute(x)))) > > to produce: > [1] "a" > [1] "b" > > and not, what it actually does: > [1] "X[[1L]]" > [1] "X[[2L]]" > $a > [1] "X[[1L]]" > > $b > [1] "X[[2L]]" > > or with l_ply (plyr package) > l_ply(data.frame(a=1:3, b=2:4), function(x) print(deparse(substitute(x)))) > > to produce: > [1] "a" > [1] "b" > > and not, what it actually does: > [1] ".data[[i]]" > [1] ".data[[i]]" > > Is this possible? > > Thanks, > Heinz > > ______________________________________________ > 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. > -- Henrique Dallazuanna Curitiba-Paraná-Brasil 25° 25' 40" S 49° 16' 22" O ______________________________________________ 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.