converting datetime string to POSIXct date/time format in R

25
votes

Consider a string in the format 

test <- "YYYY-MM-DDT00:00:00.000-08:00"

My goal is to convert those strings to POSIXct format so that I can plot the data. my initial thought was to use

as.POSIXct(test)

...but that seems to truncate the datetime to just date. Any thoughts? The help info for as.POSIXct seems to imply that the input should be date and time separated by a space, not by a "T". Is this my issue?

1
stringrdatetimeposixct
Since the XML extraction part works, and the question has nothing to do with that, I suggest editing the title of this question and removing the xml tag. - Ista

1 Answers

46
votes

You need to specify a format for your conversion. Take a read of ?strptime to see all of the options for date formats.

#YYYY-MM-DDT00:00:00.000-08:00
test <- "2013-12-25T04:32:16.500-08:00"
z <- as.POSIXct(test,format="%Y-%m-%dT%H:%M:%OS")
op <- options(digits.secs = 3)
z
#[1] "2013-12-25 04:32:16.5 EST"