Incorrect Conversion of Date as a Factor to a Date

Question

I am having trouble calculating a date that is imported in from a .csv file. What I want to do is take that date in the factor DateClosed and generate a date in a date fie

Answer 1

DateClosed <- factor(c("7/30/2007","12/12/2007", "5/8/2009"))
as.Date(DateClosed, format="%m/%d/%Y")

Produces:

[1] "2007-07-30" "2007-12-12" "2009-05-08"

Notice the capital "Y" in the format param. The lower case "y" is for 2 digit years, so as.Date reads the first two digits of the year token ("20"), and then assumes that refers to just the last two digits of the year, and adds the current date's century (also "20"), so you end up with dates in 2020.