Reputation: 621
Lets say I have a dataframe like this one:
Col1 Col2 Tag_history New_tag Col5 created
0 Name1 Value1 Tag10 Tag10 Rank4 2021-03-21 12:58:09
1 Name1 Value2 Tag10 Tag10 Rank4 2021-03-21 13:58:09
2 Name1 Value3 Tag10 Tag10 Rank4 2021-03-21 14:58:09
3 Name2 Value1 Tag8 Tag9 Rank1 2021-03-21 10:58:09
4 Name2 Value2 Tag8 Tag9 Rank1 2021-03-21 11:58:09
5 Name2 Value4 Tag8 Tag9 Rank1 2021-03-21 12:58:09
6 Name2 Value5 Tag8 Tag9 Rank1 2021-03-21 13:58:09
So, i want to compare columns Tag_history and New tag and if the tag has changed, i want to add a new row that shows in the Tag_history also the new Tag. E.g for For Name2, the tag has changed from Tag8 to Tag9, so i want my df to look like this:
Col1 Col2 Tag_history New_tag Col5 created
0 Name1 Value1 Tag10 Tag10 Rank4 2021-03-21 12:58:09
1 Name1 Value2 Tag10 Tag10 Rank4 2021-03-21 13:58:09
2 Name1 Value3 Tag10 Tag10 Rank4 2021-03-21 14:58:09
3 Name2 Value1 Tag8 Tag9 Rank1 2021-03-21 10:58:09
4 Name2 Value2 Tag8 Tag9 Rank1 2021-03-21 11:58:09
5 Name2 Value4 Tag8 Tag9 Rank1 2021-03-21 12:58:09
6 Name2 Value5 Tag8 Tag9 Rank1 2021-03-21 13:58:09
7 Name2 IDLE Tag9 Tag9 Rank1 2022-01-24 16:50:00 (current datetime)
Upvotes: 1
Views: 64
Reputation: 156
First of all, I don't recommend using any loops because they are not very effective.
different_value = df[~(df['Tag_history'] == df['New_tag'])] #First check and search for rows that contains different "Tag_history" and "New_tag"
different_value.loc[:,'New_tag'] = different_value['Tag_history'] #Create the new rows
df = df.append(different_value, ignore_index = True) # append dataframes
Upvotes: 2