First day of the month from a POSIXct date time using lubridate

Question

Given a POSIXct date time, how do you extract the first day of the month for aggregation?

library(lubridate)

full.date <- ymd_hms(\"2013-01-01 00:00:21\"         


        

Answer 1

first.of.month <- ymd(format(full.date, "%Y-%m-01"))
first.of.month

[1] "2013-01-01 UTC"