Getting previous month start date and end date from current date in R

Question

Is there any easy way for getting start date and end date of previous month from the current date in R?

I have only the current date. From it, i want to get the previous month, start date of previous month, end date of previous month.

currentDate<-Sys.Date() #return today's date as "2012-11-07" 

I want the previous month start date as 2012-10-01 and end date as 2012-10-31 from today's date.

Answer 1

A number of packages have handy date functions, but to roll your own:

A start of month function:

som <- function(x) {   as.Date(format(x, "%Y-%m-01")) } 

and an end of month function (although you won't need this here):

eom <- function(x) {   som(som(x) + 35) - 1 } 

That should get you going. For example, to get the end of the previous month:

som(Sys.Date()) - 1 [1] "2012-10-31" 

and the start of the month:

som(som(Sys.Date()) - 1) [1] "2012-10-01"