pandas replace rows from another dataframe code example

Example 1: change dataframe value by index

x    y
A  NaN  NaN
B  NaN  NaN
C  NaN  NaN

df.at['C', 'x'] = 10

Example 2: pandas replace values from another dataframe

In [36]:
df['Group'] = df['Group'].map(df1.set_index('Group')['Hotel'])
df

Out[36]:
         Date  Group  Family  Bonus
0  2011-06-09  Jamel  Laavin    456
1  2011-07-09  Frank  Grendy    679
2  2011-09-10   Luxy  Fantol    431
3  2011-11-02  Frank  Gondow    569