[R] data.frame into list by columns; merge and row.names

[Tiago R Magalhaes]

Hi

a)
I want to make a list out of a data.frame, where each element of the 
list is a column of the data.frame.
I looked in the archives and saw a lot of postings but surprsingly 
none elucidated me. I also tried the split, aggregate help files and 
counldn't see any easy way to do this. I wouldn't be surprised if 
it's there, but I really didn't see it.

I solved the problem using a very convoluted way:

x <- data.frame(a=sample(10), b=sample(10), c=sample(10))
f <- factor(names(x), levels=names(x))
xx <- data.frame(f=f, t(x))
xlist.transpose <- split(xx, xx$f)
xlist <- lapply(xlist, function(x) x=t(x))

I am very convinced there's a much easier way, so if any of you 
people enlighten me I would appreciate

b)
In terms of my own personal use, it would be much better that merge 
when using 'row.names' as the by argument would output a data.frame 
with the merged row.names and not a column 'Row.names'.

Also it would be great if it would be possible to choose wich sorting 
would be the final one - right now the default is argument y, but 
sometimes argument x is much more useful
Of course these are minor points and can be dealt very easily after 
calling merge, but here it goes my comment anyway.