[FIXED] Compare two dataframes and write the differences to another dataframe

Issue

I have two dataframes. df1 and df2

import pandas as pd

df1 = pd.DataFrame({
'Buyer': ['Carl', 'Alex', 'Lauren'],
'Quantity': [18, 3, 8]})

df2 = pd.DataFrame({
'Buyer': ['Carl', 'Alex', 'Maya', 'Emily'],
'Quantity': [18, 3, 5, 5]})

I was wondering if there was a way to compare df1 with df2 and append whatver is in not df1 to df2 so I will have an end result like

df2 = pd.DataFrame({
'Buyer': ['Carl', 'Alex', 'Maya', 'Emily', 'Lauren'],
'Quantity': [18, 3, 5, 5, 8]})

Solution

You just need to concat the two dfs and then drop dupes

df2 = pd.concat([df1,df2]).drop_duplicates()

>>> df2
    Buyer  Quantity
0    Carl        18
1    Alex         3
2  Lauren         8
2    Maya         5
3   Emily         5

Answered By - Boskosnitch