Merge Dataframe
In [1]:
# Inner Join
import pandas as pd
df1 = pd.DataFrame({
'A': ['A0', 'A1', 'A2'],
'B': ['B0', 'B1', 'B2'],
'key': ['K0', 'K1', 'K2']
})
df2 = pd.DataFrame({
'C': ['C0', 'C1', 'C2'],
'D': ['D0', 'D1', 'D2'],
'key': ['K0', 'K1', 'K2']
})
result = pd.merge(df1, df2, on='key')
print(result)
A B key C D 0 A0 B0 K0 C0 D0 1 A1 B1 K1 C1 D1 2 A2 B2 K2 C2 D2
In [2]:
# Left Join
import pandas as pd
df1 = pd.DataFrame({
'A': ['A0', 'A1', 'A2'],
'B': ['B0', 'B1', 'B2'],
'key': ['K0', 'K1', 'K2']
})
df2 = pd.DataFrame({
'C': ['C0', 'C1', 'C2'],
'D': ['D0', 'D1', 'D2'],
'key': ['K0', 'K1', 'K3']
})
result = pd.merge(df1, df2, on='key', how='left')
print(result)
A B key C D 0 A0 B0 K0 C0 D0 1 A1 B1 K1 C1 D1 2 A2 B2 K2 NaN NaN
In [3]:
# Right Join
import pandas as pd
df1 = pd.DataFrame({
'A': ['A0', 'A1', 'A2'],
'B': ['B0', 'B1', 'B2'],
'key': ['K0', 'K1', 'K2']
})
df2 = pd.DataFrame({
'C': ['C0', 'C1', 'C2'],
'D': ['D0', 'D1', 'D2'],
'key': ['K0', 'K1', 'K3']
})
result = pd.merge(df1, df2, on='key', how='right')
print(result)
A B key C D 0 A0 B0 K0 C0 D0 1 A1 B1 K1 C1 D1 2 NaN NaN K3 C2 D2
In [4]:
# Outer Join
import pandas as pd
df1 = pd.DataFrame({
'A': ['A0', 'A1', 'A2'],
'B': ['B0', 'B1', 'B2'],
'key': ['K0', 'K1', 'K2']
})
df2 = pd.DataFrame({
'C': ['C0', 'C1', 'C2'],
'D': ['D0', 'D1', 'D2'],
'key': ['K0', 'K1', 'K3']
})
result = pd.merge(df1, df2, on='key', how='outer')
print(result)
A B key C D 0 A0 B0 K0 C0 D0 1 A1 B1 K1 C1 D1 2 A2 B2 K2 NaN NaN 3 NaN NaN K3 C2 D2