[R] subtract 2 columns in a data.frame

[Ulrich Leopold]

Dear list,

could someone point me to the right command to subtract 2 columns in a
data.frame. Might be a bit embarrassing question. But I cannot figure
out how to do this simple command in R.

Thanks, Ulrich
-- 
__________________________________________________

Ulrich Leopold MSc.

Department of Physical Geography
Institute for Biodiversity and Ecosystem Dynamics
Faculty of Science
University of Amsterdam
Nieuwe Achtergracht 166
NL-1018WV Amsterdam

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Email:	uleopold at science.uva.nl
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