pandas.DataFrame.apply

DataFrame.apply(func, axis=0, broadcast=False, raw=False, reduce=True, args=(), **kwds)

Applies function along input axis of DataFrame.

Objects passed to functions are Series objects having index either the DataFrame’s index (axis=0) or the columns (axis=1). Return type depends on whether passed function aggregates

Parameters :

func : function

Function to apply to each column/row

axis : {0, 1}

• 0 : apply function to each column
• 1 : apply function to each row

broadcast : boolean, default False

For aggregation functions, return object of same size with values propagated

reduce : boolean, default True

Try to apply reduction procedures

raw : boolean, default False

If False, convert each row or column into a Series. If raw=True the passed function will receive ndarray objects instead. If you are just applying a NumPy reduction function this will achieve much better performance

args : tuple

Positional arguments to pass to function in addition to the array/series

Additional keyword arguments will be passed as keywords to the function

Returns :

applied : Series or DataFrame

See also

DataFrame.applymap

For elementwise operations

Examples

>>> df.apply(numpy.sqrt) # returns DataFrame
>>> df.apply(numpy.sum, axis=0) # equiv to df.sum(0)
>>> df.apply(numpy.sum, axis=1) # equiv to df.sum(1)