r - Change day of the month in a Date to first day (01)

Question

I want to set the day of month in a Date to start date of current month (01). Now I use the following:

currentDate <- Sys.Date()  #for getting current system date eg:2012-11-06
formatDate <- format(currentDate, "%Y-%m")  #it return 2012-11
startDate <- as.Date(paste(formatDate, "-01", sep = ""))
# 2012-11-01 

Is there any easy way to do this?

Answer 1

Yes, there is a one-liner for that using function cut:

cut(Sys.Date(), "month")
[1] 2012-11-01
Levels: 2012-11-01