问题
I'm trying to convert a timestamp in microseconds to the following format in R:
YYYY-MM-DD HH:MM:SS
I've tried different approaches, but couldn't succeed. Following my code:
options(digits=16)
value = 1521222492687300
as.POSIXct(value, tz = "UTC", origin="1970-01-01 00:00:00")
And I get this as return:
[1] "48207591-10-13 12:15:00 UTC"
Even divided by 1000, as some posts suggested, I'm still getting a non sense result:
as.POSIXct(value/1000, tz = "UTC", origin="1970-01-01 00:00:00")
[1] "50175-08-15 19:31:27.300048 UTC"
Any suggestion to solve this problem?
回答1:
As Gabor hinted you need to divide by 1e6, not 1e3:
R> v <- 1521222492687300
R> v
[1] 1.52122e+15
R> anytime::anytime(v / 1e6)
[1] "2018-03-16 12:48:12.6872 CDT"
R>
Same of course with as.POSIXct etc but you nee to supply the redundant origin:
R> as.POSIXct(v / 1e6, origin="1970-01-01")
[1] "2018-03-16 12:48:12.6872 CDT"
R>
One way to see your scale is to convert current time:
R> w <- as.numeric(Sys.time())
R> c(v, w)
[1] 1.52122e+15 1.52346e+09
R>
which makes the scaling difference more obvious.
来源：https://stackoverflow.com/questions/49776854/converting-timestamp-in-microseconds-to-data-and-time-in-r