DataFrame.unstack()

DataFrame.unstack(level=-1, fill_value=None) [source]

Pivot a level of the (necessarily hierarchical) index labels, returning a DataFrame having a new level of column labels whose inner-most level consists of the pivoted index labels. If the index is not a MultiIndex, the output will be a Series (the analogue of stack when the columns are not a MultiIndex). The level involved will automatically get sorted.

Parameters:

Parameters:	level : int, string, or list of these, default -1 (last level) Level(s) of index to unstack, can pass level name fill_value : replace NaN with this value if the unstack produces missing values
Returns:	unstacked : DataFrame or Series

level : int, string, or list of these, default -1 (last level)

Level(s) of index to unstack, can pass level name

fill_value : replace NaN with this value if the unstack produces

missing values

Returns:

unstacked : DataFrame or Series

Examples

>>> index = pd.MultiIndex.from_tuples([('one', 'a'), ('one', 'b'),
...                                    ('two', 'a'), ('two', 'b')])
>>> s = pd.Series(np.arange(1.0, 5.0), index=index)
>>> s
one  a   1.0
     b   2.0
two  a   3.0
     b   4.0
dtype: float64

>>> s.unstack(level=-1)
     a   b
one  1.0  2.0
two  3.0  4.0

>>> s.unstack(level=0)
   one  two
a  1.0   3.0
b  2.0   4.0

>>> df = s.unstack(level=0)
>>> df.unstack()
one  a  1.0
     b  2.0
two  a  3.0
     b  4.0
dtype: float64

Links:

http://pandas.pydata.org/pandas-docs/version/0.19.2/generated/pandas.DataFrame.unstack.html

doc_Pandas

2025-01-10 15:47:30

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