Hi again, Let say I have below 2 data frames.
OriginalData = data.frame('Value1' = 1:12, 'Value2' = 11:22, 'AA1' = c('AA4', 'AA3', 'AA4', 'AA1', 'AA2', 'AA1', 'AA6', 'AA6', 'AA3', 'AA3', 'AA4', 'AA3'), 'Value' = NA) TargetValue = data.frame('AA' = c('AA1', 'AA2', 'AA3', 'AA4', 'AA5', 'AA6'), 'BB' = c('B', 'B', 'B', 'B', 'CC', 'CC'), 'Value' = c(5, 10, 25, 7, 35, 21)) OriginalData TargetValue Now I need to replace OriginalData's 'AA1' column with TargetValue's 'BB' column, based on matched values between 'AA1' & 'AA' columns of OriginalData & TargetValue respectively. With this same law, I need to update 'Value' column of OriginalData with that of TargetValue. As an example, after replacement by above rule, 1st row of OriginalData should look like : > OriginalData Value1 Value2 AA1 Value 1 1 11 B 7 Values of TargetValue's 'AA' column are unique i.e. no duplication Previously I have implemented a 'for' loop to implement above, however since both of my data.frames are quite big, it is taking long time to execute. Is there any 'R' way to implement this quickly. Appreciate for any pointer. Thanks, ______________________________________________ R-help@r-project.org mailing list -- To UNSUBSCRIBE and more, see 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.