Hi, I'm a bit stuck and need some help with R code to code a variable F_R based on a combination of conditions.
The first condition would code F_R as "F" and would be based on the min(Date) and Min(Time) for each combination of UniqueID & Reason. The second condition would code the variable as "R" as it would be the rest of the data that dont meet the first condition. For example: for "UID 1" & "Reason 1" the first record would be coded "F" and the 4th record would be coded "R". UniqueID Reason Date Time 1 UID 1 Reason 1 19/12/2010 15:00 2 UID 1 Reason 2 19/12/2010 16:00 3 UID 1 Reason 3 19/12/2010 16:30 4 UID 1 Reason 1 20/12/2010 08:00 5 UID 1 Reason 2 20/12/2010 10:01 6 UID 1 Reason 3 20/12/2010 11:30 7 UID 1 Reason 1 21/12/2010 12:45 8 UID 1 Reason 2 21/12/2010 18:44 9 UID 1 Reason 3 21/12/2010 19:29 10 UID 2 Reason 1 19/12/2010 17:00 11 UID 2 Reason 2 19/12/2010 18:00 12 UID 2 Reason 3 19/12/2010 18:10 13 UID 2 Reason 1 20/12/2010 13:00 14 UID 2 Reason 2 20/12/2010 13:30 15 UID 2 Reason 3 20/12/2010 16:15 Is a loop the most efficient way to do this or is there some pre-existing function that can help me with this? The sample dataset is what is given below. Thanks in advance, Raoul -- View this message in context: http://r.789695.n4.nabble.com/Coding-a-new-variable-based-on-criteria-in-a-dataset-tp3145176p3145176.html Sent from the R help mailing list archive at Nabble.com. ______________________________________________ R-help@r-project.org mailing list https://stat.ethz.ch/mailman/listinfo/r-help PLEASE do read the posting guide http://www.R-project.org/posting-guide.html and provide commented, minimal, self-contained, reproducible code.