用于与pandas.DataFrame.reset_index做对比
DataFrame.
set_index
(
keys,
drop=True,
append=False,
inplace=False,
verify_integrity=False
)
[source]
Set the DataFrame index (row labels) using one or more existing columns. By default yields a new object.
| Parameters: | keys : column label or list of column labels / arrays drop : boolean, default True
append : boolean, default False
inplace : boolean, default False
verify_integrity : boolean, default False
|
|---|---|
| Returns: | dataframe : DataFrame |
Examples
>>> df = pd.DataFrame({'month': [1, 4, 7, 10],
... 'year': [2012, 2014, 2013, 2014],
... 'sale':[55, 40, 84, 31]})
month sale year
0 1 55 2012
1 4 40 2014
2 7 84 2013
3 10 31 2014
Set the index to become the ‘month’ column:
>>> df.set_index('month')
sale year
month
1 55 2012
4 40 2014
7 84 2013
10 31 2014
Create a multi-index using columns ‘year’ and ‘month’:
>>> df.set_index(['year', 'month'])
sale
year month
2012 1 55
2014 4 40
2013 7 84
2014 10 31
Create a multi-index using a set of values and a column:
>>> df.set_index([[1, 2, 3, 4], 'year'])
month sale
year
1 2012 1 55
2 2014 4 40
3 2013 7 84
4 2014 10 31
