Find out the number of days of a month in R

Question

I have a date in P

 date = as.Date("2011-02-23", "%Y-%m-%d") 

Is it possible to find out the number of days of the month of that particular date? (With respect to leapyears). In PHP it would look similar to this (http://www.php.net/manual/en/function.date.php):

days = format(date, "%t") 

but "%t" seems to have a different meaning in R. Is there a solution for this problem?

Answer 1

lubridate package has required function "days_in_month" with respect to leapyears.

Your example:

    date <- as.Date("2011-02-23", "%Y-%m-%d")     lubridate::days_in_month(date)     # Feb     # 28 

Leap year (2016):

    date_leap <- as.Date("2016-02-23", "%Y-%m-%d")     lubridate::days_in_month(date_leap)     # Feb      # 29 

Answer 2

The Hmisc library has a couple of helpful functions for doing this:

require(Hmisc) monthDays(as.Date('2010-01-01'))