Message-ID: <CABdHhvGC8ryWVaJnH=S5-gt-SBMD=bxPwzxA_Dxq+yW=HDBwGQ@mail.gmail.com>
Date: 2011-12-24T02:22:18Z
From: Hadley Wickham
Subject: cast in reshape and reshape2
In-Reply-To: <CAOHtMfUG3SgHTZM+wkOTzb0oqaXeYFas_DYYw1_8-unv2d3pdw@mail.gmail.com>
On Fri, Dec 23, 2011 at 1:58 PM, Kaiyin Zhong <kindlychung at gmail.com> wrote:
>> library(reshape2)
>> x = melt(airquality, id=c('month', 'day'))
>
> With reshape I can cast with multiple functions:
>
>> library(reshape)
>> cast(x, month+variable~., c(mean,sd))
> ? month variable ? ? ? mean ? ? ? ? sd
> 1 ? ? ?5 ? ?ozone ?23.615385 ?22.224449
> 2 ? ? ?5 ?solar.r 181.296296 115.075499
> 3 ? ? ?5 ? ? wind ?11.622581 ? 3.531450
> 4 ? ? ?5 ? ? temp ?65.548387 ? 6.854870
> 5 ? ? ?6 ? ?ozone ?29.444444 ?18.207904
> 6 ? ? ?6 ?solar.r 190.166667 ?92.882975
> 7 ? ? ?6 ? ? wind ?10.266667 ? 3.769234
> 8 ? ? ?6 ? ? temp ?79.100000 ? 6.598589
> 9 ? ? ?7 ? ?ozone ?59.115385 ?31.635837
> 10 ? ? 7 ?solar.r 216.483871 ?80.568344
> 11 ? ? 7 ? ? wind ? 8.941935 ? 3.035981
> 12 ? ? 7 ? ? temp ?83.903226 ? 4.315513
> 13 ? ? 8 ? ?ozone ?59.961538 ?39.681210
> 14 ? ? 8 ?solar.r 171.857143 ?76.834943
> 15 ? ? 8 ? ? wind ? 8.793548 ? 3.225930
> 16 ? ? 8 ? ? temp ?83.967742 ? 6.585256
> 17 ? ? 9 ? ?ozone ?31.448276 ?24.141822
> 18 ? ? 9 ?solar.r 167.433333 ?79.118280
> 19 ? ? 9 ? ? wind ?10.180000 ? 3.461254
> 20 ? ? 9 ? ? temp ?76.900000 ? 8.355671
>
> Is there a way to do the same job with reshape2?
No, this is something that reshape2 does not support.
Hadley
--
Assistant Professor / Dobelman Family Junior Chair
Department of Statistics / Rice University
http://had.co.nz/