how to calculate recency(RFM) from a given date attribute in R

Question

custid  tot_prod       tot_rev          Last_tran   total_trans

1 1002 13 1465.25 11/23/2011 4 2 1003 2 353.25 1/1/2011 1 3 1004 12 2466.5 11/25/2011 12

Above is the Retail dataset of customer. I need to calculate recency(a new attribute when the customer is last seen) from last transaction(last_tran) in terms of month.i.e. he purchased in last 3 months or last 6 months or may be one year in R. please suggest.

Answer 1

Try this

as.POSIXct(Sys.Date(), format= "%Y-%m-%d", tz="UCT") - as.POSIXct("11/25/2011", format = "%m/%d/%Y",tz="UCT")

More vectorized operation in your situation

as.POSIXct(Sys.Date(), format= "%Y-%m-%d", tz="UCT") - as.POSIXct(Last_tran, format = "%m/%d/%Y",tz="UCT")