[R] Data frames questions

[Jonathan Greenberg]

Hi there, couple of questions on data frames:

1) Is there a way to build an empty data frame, containing nothing but the
data frame variable names?
2) Is there a way to reorder the variables in a data frame, e.g. When I go
to write out a data frame using write.table or write.matrix, I want the
output in a certain order...
3) How to I "append" to the bottom of a dataframe?

Thanks!

--j

-- 
Jonathan A. Greenberg, PhD
NRC Research Associate
NASA Ames Research Center
MS 242-4
Moffett Field, CA 94035-1000
Office: 650-604-5896
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