bigframes.pandas.DataFrame.set_index#
- DataFrame.set_index(keys: Hashable | Sequence[Hashable], append: bool = False, drop: bool = True) DataFrame[source]#
Set the DataFrame index using existing columns.
Set the DataFrame index (row labels) using one existing column. The index can replace the existing index.
Examples:
>>> df = bpd.DataFrame({'month': [1, 4, 7, 10], ... 'year': [2012, 2014, 2013, 2014], ... 'sale': [55, 40, 84, 31]}) >>> df month year sale 0 1 2012 55 1 4 2014 40 2 7 2013 84 3 10 2014 31 [4 rows x 3 columns]
Set the ‘month’ column to become the index:
>>> df.set_index('month') year sale month 1 2012 55 4 2014 40 7 2013 84 10 2014 31 [4 rows x 2 columns]
Create a MultiIndex 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 [4 rows x 1 columns]
- Parameters:
keys – A label. This parameter can be a single column key.
drop – Delete columns to be used as the new index.
- Returns:
Changed row labels.
- Return type:
- Raises:
KeyError – If key(s) are not in the columns.