R help - Sep 2009 - Is there any performance difference between subset() and list comprehension?

Hello,

Suppose that you have a data frame 'df' with variables 'V1',
'V2', 'V3',
etc.
Is there any (performance) difference (except the difference of the return
types)
between the following two computations?


subset(df, V1 > 0, V2)

and

df$V2[df$V1 > 0]


Best Regards,
hyunjo

	[[alternative HTML version deleted]]

On Sat, 26 Sep 2009 15:26:12 +0900 You Hyun Jo <youhyunjo at gmail.com>
wrote:

YHJ> Is there any (performance) difference (except the difference of
YHJ> the return types)
YHJ> between the following two computations?

Try it yourself. 
?system.time
is useful for that purpose.

Stefan