Converting timestamp in seconds to a date format in R

Question

I have a table (tags) with a column for timestamp (ts), which is formatted as seconds since 1 Jan, 1970 GMT. I'm trying to create a date column that converts the timestamp from seconds to date and time EST.

The suggested code for R was:

tags$date<-strptime(tags$ts, "%Y-%m-%d")
tags$date<-as.POSIXct(tags$date)

But when I do this, tags$date comes up as NA. Any suggestions for what I might be doing wrong? Thanks.

welcome to stackoverflow. please read [how to write a good R question](https://stackoverflow.com/q/5963269/3250126). Use `dput(head(tags))` to share a sample of your data. — loki, Oct 04 '17 at 11:48

Pop · Answer 1 · 2017-10-04T11:59:15.757

4

You should us as.POSIXct function instead:

tags$date <- as.POSIXct(tags$ts, origin="1970-01-01", tz="US/New York")

strptime converts between character representations and dates not between timestamp and dates.

edited Oct 04 '17 at 11:59

answered Oct 04 '17 at 11:47

Pop

11,817
4
53
67

1

Also required the time in timezone EST so would be something like tags$date – ngamita Oct 04 '17 at 11:57
You're right I forgot the timezone. Just edited my answer. Thanks – Pop Oct 04 '17 at 11:59

score 1 · Answer 2 · answered Oct 04 '17 at 12:24

1

Here's a lubridate version. When we use as_datetime we don't need to explicitly specify an origin as it defaults to the desired origin.

lubridate::as_datetime(1507119276, tz='EST')
# [1] "2017-10-04 07:14:36 EST"

answered Oct 04 '17 at 12:24

Paul

7,801
1
22
34

Converting timestamp in seconds to a date format in R

2 Answers2