set first column as index in dataframe code example

Example 1: how to change indeces in pandas dataframe

>>> df.set_index('month')
       year  sale
month
1      2012    55
4      2014    40
7      2013    84
10     2014    31

Example 2: change index to dataframe pandas

#cree un indice par defaut sur la base de donnee
df.reset_index()