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Pandas merge question - smw10c - May-05-2017
I hope you are all having a good day. I want to know why my merge below is returning the key error that is stated below my code. Any help would be appreciated.
import pandas as pd
import numpy as np
import matplotlib.pyplot as plt
import seaborn as sns
%matplotlib inline
dict1={'eggs':(1,7,44,76,23,56,22,21,20,11,12,81),'month':('jan','feb','mar','apr','may','jun','jul','aug','sep','oct','nov','dec')}
dict2={'bread':(22,43,17,9,22,16,71,82,24,34,54,45),'months':('jan','feb','mar','apr','may','jun','jul','aug','sep','oct','nov','dec')}
df1=pd.DataFrame(dict1)
df2=pd.DataFrame(dict2)
df1.columns.values[1]='months'
pd.merge(left=df1,right=df2,on='months')KeyError: 'months'
RE: Pandas merge question - zivoni - May-05-2017
Your example works for me. Perhaps you forgot to run line 15 (that renames month column as months column), so there was no 'months' key in df1 and merge failed?
RE: Pandas merge question - hussainmujtaba - Jul-02-2020
The code works perfectly with this output
Output: eggs months bread
0 1 jan 22
1 7 feb 43
2 44 mar 17
3 76 apr 9
4 23 may 22
5 56 jun 16
6 22 jul 71
7 21 aug 82
8 20 sep 24
9 11 oct 34
10 12 nov 54
11 81 dec 45Check out this pandas tutorial to know more