[R] Time data
jholtman at gmail.com
Thu Apr 14 13:18:17 CEST 2011
It depends on how you want to work with the data. Here is an example
of converting both to POSIXct and a numeric value:
> x <- c('1:24', '13:46')
> # convert to POSIXct
> x.POSIXct <- as.POSIXct(x, format = '%H:%M')
 "2011-04-14 01:24:00 EDT" "2011-04-14 13:46:00 EDT"
> # to get a numeric value representing the hour
> x.hour <- do.call(rbind, strsplit(x, ":")) # create matrix
> # convert to numeric
> mode(x.hour) <- 'numeric'
> # convert to hour
> x.hour %*% c(1, 1/60)
On Wed, Apr 13, 2011 at 5:29 PM, Gregory Pierce
<pierce.gregory at gmail.com> wrote:
> Hello fellow R-users,
> I have a data set that includes times in the hh:mm format. I am uncertain
> how to tell R that it is time data. Currently when I try to calculate a mean
> with this time subset, I get an error message:
>  NA
> Warning message:
> In mean.default(mar2011stats$TT) :
> argument is not numeric or logical: returning NA
> TT is the column label under which I have stored my time data: (for example,
> 1:24 to represent one hour and twenty four minutes).
> Do I have to convert everything to minutes so that R can deal with it as it
> would other numerical values?
> [[alternative HTML version deleted]]
> R-help at r-project.org mailing list
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> and provide commented, minimal, self-contained, reproducible code.
Data Munger Guru
What is the problem that you are trying to solve?
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