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.hodg...@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.hodg...@gmail.com > > [[alternative HTML version deleted]] > > ______________________________________________ > R-help@r-project.org mailing list > https://stat.ethz.ch/mailman/listinfo/r-help > PLEASE do read the posting guide http://www.R-project.org/posting-guide.html > and provide commented, minimal, self-contained, reproducible code. ______________________________________________ R-help@r-project.org mailing list https://stat.ethz.ch/mailman/listinfo/r-help PLEASE do read the posting guide http://www.R-project.org/posting-guide.html and provide commented, minimal, self-contained, reproducible code.