Something like this...untested
I think cbind recicles the last value(31) since nov and dec are of different length
nov <- kuantan.dt[(kuantan.dt$Bulan >=11);nov
dec <- kuantan.dt[(kuantan.dt$Bulan >=12);dec
both <- cbind(nov,dec)
# get the first 30 records
both <- head(both,30);both


Felipe D. Carrillo
Supervisory Fishery Biologist
Department of the Interior
US Fish & Wildlife Service
California, USA
http://www.fws.gov/redbluff/rbdd_jsmp.aspx


From: Roslina Zakaria <zroslina@yahoo.com>
>To: "r-help@r-project.org" <r-help@r-project.org> 
>Sent: Sunday, November 11, 2012 6:39 PM
>Subject: [R] arrange data
>
>Dear r-users,
> 
>I have daily rainfall data from 1971 to 2000.  I would like to extract november and december data only.  I would also like to do column bind for november and december, therefore I would like to delete 31 December from december data so that the length of november and december are the same.  Hope somebody can help me.  I tried this below:
> 
>> kuantan.dt.1 <- kuantan.dt[(kuantan.dt$Bulan >=11) & (kuantan.dt$Bulan <= 12),]
>> head(kuantan.dt.1) ; tail(kuantan.dt.1)
>    Tahun Bulan Hari Jumlah.Hujan.mm.
>305    71    11    1              0.0
>306    71    11    2             16.3
>307    71    11    3              0.0
>308    71    11    4              0.0
>309    71    11    5             12.2
>310    71    11    6              4.6
>      Tahun Bulan Hari Jumlah.Hujan.mm.
>10953     0    12   26              0.0
>10954     0    12   27              0.0
>10955     0    12   28             20.0
>10956     0    12   29             15.5
>10957     0    12   30              6.4
>10958     0    12   31              9.3
>    [[alternative HTML version deleted]]
>
>
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