add 2 dataframes in panda where they have the same column values code example

Example 1: add two column values of a datframe into one

df["period"] = df["Year"] + df["quarter"]

Example 2: how to add the sum of multiple columns into another column in a dataframe

print(df)
   Apples  Bananas  Grapes  Kiwis
0     2.0      3.0     NaN    1.0
1     1.0      3.0     7.0    NaN
2     NaN      NaN     2.0    3.0

df['Fruit Total']=df.iloc[:,-4:].sum(axis=1)

print(df)
   Apples  Bananas  Grapes  Kiwis  Fruit Total
0     2.0      3.0     NaN    1.0          6.0
1     1.0      3.0     7.0    NaN         11.0
2     NaN      NaN     2.0    3.0          5.0

Example 3: sum two columns pandas

sum_column = df["col1"] + df["col2"]