Why are lubridate functions so slow when compared with as.POSIXct?

Question

As the title goes. Why is the lubridate function so much slower?

library(lubridate)
library(microbenchmark)

Dates <- sample(c(dates = format(seq(ISOdate(         


        

Answer 1

@Tyler's answer is correct. Here's some more info including a tip on making lubridate faster - from the help file:

" Lubridate has an inbuilt very fast POSIX parser, ported from the fasttime package by Simon Urbanek. This functionality is as yet optional and could be activated with options(lubridate.fasttime = TRUE). Lubridate will automatically detect POSIX strings and use fast parser instead of the default strptime utility. "