converting datetime string to POSIXct date/time format in R

Question

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?

Solution

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"

Comments

[Ista]

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.

[Dan]

Hey, thanks for your answer here. I have a Question too...chr [1:10000] "2016-05-30 23:39:51 UTC" "2016-05-30 23:52:34 UTC" is my data. So i get it to convert with as.POSIXct: as.POSIXct(df$event_ts_utc,format="%Y-%m-%d %H:%M:%OS") working fine, except for the TIMECODE "2016-05-30 23:39:51 CEST"! Any Ideas?

[Dan]

did it! as.POSIXct(df$event_ts_utc,format="%Y-%m-%d %H:%M:%S", tz = "UTC")

[stevec]

I had a slightly differently formatted date time stamp, so for me what worked was: as.POSIXct("2019-03-15 16:17:42" , format="%Y-%m-%d %H:%M:%OS")