Deleting rows that are duplicated in one column based on the conditions of another column
date, duplicates, r
Solution
Lets say you have data in df
df = df[order(df[,'Date'],-df[,'Depth']),]
df = df[!duplicated(df$Date),]
Problem
Here is an example of my data set; ``` Date Time(GMT) Depth Temp Salinity Density Phosphate 24/06/2002 1000 1 33.855 0.01 24/06/2002 1000 45 33.827 0.01 01/07/2002 1000 10 13.26 33.104 24.873 0.06 01/07/2002 1000 30 12.01 33.787 25.646 0.13 08/07/2002 1000 5 13.34 33.609 25.248 0.01 08/07/2002 1000 40 12.01 34.258 26.011 1.33 15/07/2002 1000 30 12.04 34.507 26.199 0.01 22/07/2002 1000 5 13.93 33.792 25.269 0.01 22/07/2002 1000 30 11.9 34.438 26.172 0.08 29/07/2002 1000 5 13.23 34.09 25.642 0.01 ``` I want to delete duplicate rows so that I only have one row per date, I want to do this based on the Depth, I would like to keep the row with the greatest (deepest) depth. Any ideas?