R Extract Hours from Time in factor Format

Question

I have a vector of time that is in the format of factor. For instance, Time[1] is 8:01:01, class(Time[1]) is factor.

Now I want to extract hours and minute from this vector. What is the most computational efficient way of doing it? My vector is very large. Thank you so much,

Answer 1

Try this:

format(strptime(Time,"%H:%M:%S"),'%H:%M') [1] "08:01" 

Answer 2

One way with the lubridate package would be:

Time <- factor("08:01:01")
lubridate::hms(as.character(Time))

Edit

To extract hours and minutes:

library(lubridate)
Time <- factor("08:01:01")

# parese date
a <- hms(as.character(Time))

# get hours
hour(a)

# get minutes
minute(a)