Hi Erin,
"Best" is subjective, but I like
library(lubridate)
library(plyr)
xb.df <- mutate(xb.df,
time = ymd(time, truncated = 1),
year = year(time),
quarter = quarter(time))
Best,
Ista
On Mon, Feb 17, 2014 at 7:35 PM, Erin Hodgess <erinm.hodgess at gmail.com>
wrote:> Hello!
>
> I generate the following two data frames:
>
>> xa.df <- data.frame(x=rnorm(10),time=2001:2010)
>> xa.df
> x time
> 1 -1.73207086 2001
> 2 -0.84014049 2002
> 3 -0.02332163 2003
> 4 -1.47236670 2004
> 5 -0.17736265 2005
> 6 -1.27134314 2006
> 7 -2.53425374 2007
> 8 0.79132952 2008
> 9 1.16574188 2009
> 10 1.99660600 2010
>> tim1 <-
c("2010-01","2010-02","2010-03","2010-04","2011-01","2011-02",
> + "2011-03","2011-04")
>> xb.df <- data.frame(y=rnorm(8),time=tim1)
>> xb.df
> y time
> 1 -1.5175587 2010-01
> 2 1.2035292 2010-02
> 3 -0.7313063 2010-03
> 4 -1.5544370 2010-04
> 5 -0.5907269 2011-01
> 6 1.0634754 2011-02
> 7 0.9029293 2011-03
> 8 0.5996780 2011-04
>>
>
> What is the best way to turn the time columns into date objects (annual and
> quarterly)?
>
> Thanks,
> Erin
>
>
> --
> Erin Hodgess
> Associate Professor
> Department of Computer and Mathematical Sciences
> University of Houston - Downtown
> mailto: erinm.hodgess at gmail.com
>
> [[alternative HTML version deleted]]
>
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