Try this:
aggregate(TEMP ~ Year + Month + Day, DF, mean)
On Tue, Nov 16, 2010 at 4:48 PM, facehappywy <yiw010@gmail.com> wrote:
>
> Thanks every one first.
>
> I have a dataset like this
>
> Year Month Day Hour DIR SPD (m/s) SKYCOVER
> TEMP (C) RH(%)
> 2009 1 1 0 310 13.85824 3 -5 23
> 2009 1 1 1 330 14.30528 3
> -7.222222222 26
> 2009 1 1 2 320 10.72896 3
> -7.222222222 24
> 2009 1 1 3 320 10.72896 3
> -6.666666667 23
> 2009 1 1 4 320 10.28192 3
> -7.222222222 26
> 2009 1 1 5 330 10.28192 3
> -7.222222222 26
> 2009 1 1 6 330 10.28192 3
> -7.222222222 25
> 2009 1 1 6 320 12.96416 3
> -7.222222222 26
> 2009 1 1 7 330 11.176 3 -7.222222222 26
> 2009 1 1 8 330 10.72896 3
> -7.777777778 28
> 2009 1 1 9 330 10.72896 3
> -7.777777778 27
> 2009 1 1 9 320 11.176 3 -7.222222222 26
> 2009 1 1 10 320 12.51712 3
> -7.777777778 24
> 2009 1 1 11 310 9.83488 3 -7.777777778 24
> 2009 1 1 12 310 9.83488 3 -8.333333333 25
> 2009 1 1 12 310 10.72896 3
> -8.888888889 26
> 2009 1 1 13 320 9.83488 3 -7.777777778 26
> 2009 1 1 14 310 9.83488 3 -7.222222222 23
> 2009 1 1 15 310 9.83488 3 -7.222222222 23
> 2009 1 1 15 320 10.72896 0
> -7.222222222 23
> 2009 1 1 16 320 8.04672 0 -6.111111111 21
> 2009 1 1 17 300 9.83488 0 -3.888888889 18
> 2009 1 1 18 300 9.83488 0 -4.444444444 19
> 2009 1 1 18 310 9.38784 0 -2.777777778 16
> 2009 1 1 19 320 7.59968 3 -2.777777778 16
> 2009 1 1 20 310 6.25856 3 -2.777777778 18
> 2009 1 1 21 310 6.25856 3 -2.777777778 18
> 2009 1 1 21 310 7.15264 3 -2.777777778 16
> 2009 1 1 22 310 7.59968 3 -2.777777778 16
> 2009 1 1 23 300 5.81152 3 -3.888888889 16
>
>
> It is a one year (2009), 12 month, every day, every hour data. Notice that
> there are sometimes several readings within one hour. I want to calculate
> the hourly avg for each day in each month. Anyone could help me on this.
> --
> View this message in context:
>
http://r.789695.n4.nabble.com/Please-help-me-on-a-simple-avg-question-tp3045440p3045440.html
> Sent from the R help mailing list archive at Nabble.com.
>
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>
--
Henrique Dallazuanna
Curitiba-Paraná-Brasil
25° 25' 40" S 49° 16' 22" O
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