How to parse milliseconds?

问题

How do I use strptime or any other functions to parse time stamps with milliseconds in R?

time[1]
# [1] \"2010-01-15 13:55:23.975\"
strptime(time[1], format=\"%Y-%m-%d %H:%M:%S.%f\")
# [1] NA
strptime(time[1], format=\"%Y-%m-%d %H:%M:%S\")
# [1] \"2010-01-15 13:55:23\"`

回答1:

Courtesy of the ?strptime help file (with the example changed to your value):

 z <- strptime("2010-01-15 13:55:23.975", "%Y-%m-%d %H:%M:%OS")
 z # prints without fractional seconds
 op <- options(digits.secs=3)
 z
 options(op) #reset options

回答2:

You can also use strptime(time[1], "%OSn") where 0 <= n <= 6, without having to set digits.secs.

来源：https://stackoverflow.com/questions/2150138/how-to-parse-milliseconds