[R] subtract 2 columns in a data.frame

[Ko-Kang Kevin Wang]

On 4 Sep 2003, Ulrich Leopold wrote:

> 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.

Suppose your data frame is called foo, and you want the first column minus 
the second:
  foo[,1] - foo[,2]


-- 
Cheers,

Kevin

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Ko-Kang Kevin Wang
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