PYTHON

pandas add two string columns

# if both columns are strings, you can concatenate them directly
df["period"] = df["Year"] + df["quarter"]

# If one (or both) of the columns are not string typed, you should convert it 
# (them) first,
df["period"] = df["Year"].astype(str) + df["quarter"]

pandas dataframe add two columns int and string

df = df['Day'].map(str) + '-' + df['Month'].map(str) + '-' + df['Year'].map(str)

pandas dataframe add two columns int and string

df1 = df['1st Column Name'].map(str) + df['2nd Column Name'].map(str) + ...

add values from 2 columns to one pandas

df['Fruit Total']= df.iloc[:, -4:-1].sum(axis=1)
print (df)
   Apples  Bananas  Grapes  Kiwis  Fruit Total
0     2.0      3.0     NaN    1.0          5.0
1     1.0      3.0     7.0    NaN         11.0
2     NaN      NaN     2.0    3.0          2.0