Displaying 1 result from an estimated 1 matches for "tp1566260p1566801".
2010 Feb 23
4
First. Last. Data row selection
I am in the process of switching from SAS over to R. I am working on very
large CSV datasets that contain vehicle information. As I am processing the
data, I need to select the first (or sometimes the second) record (by date)
for any records that have the same license plate number. In SAS, there is a
function called 'first.' that can be used on sorted datasets to pull out
those first