[Rd] calculating means per group
RFTW
l.temarvelde at nioo.knaw.nl
Thu Sep 4 09:06:44 CEST 2008
Hi all
I have a very basic question, yet i have not found how to do it.
Suppose my dataset looks like this:
Year Area value
1 a 20
1 a 25
1 a 28
1 a 31
1 a 23
1 b 25
1 b 28
1 b 23
1 b 19
2 a 25
2 a 23
2 a 24
2 a 26
2 b 27
2 b 28
2 b 20
2 b 25
2 b 28
Now, i want to calculate a MEAN per year per area. How do i do that?
With mean(value) i calculate the mean of all values of course. I just need
to know how to group year and area correctly.
I assume that i can use this grouping in other calculations too, right?
Cheers,
Luc
--
View this message in context: http://www.nabble.com/calculating-means-per-group-tp19271479p19271479.html
Sent from the R devel mailing list archive at Nabble.com.
More information about the R-devel
mailing list