pandas.DataFrame.applymap

DataFrame.applymap(func) [source]

Apply a function to a Dataframe elementwise.

This method applies a function that accepts and returns a scalar to every element of a DataFrame.

Parameters:

func : callable

Python function, returns a single value from a single value.

Returns:

DataFrame

Transformed DataFrame.

See also

DataFrame.apply
Apply a function along input axis of DataFrame

Examples

>>> df = pd.DataFrame([[1, 2.12], [3.356, 4.567]])
>>> df
       0      1
0  1.000  2.120
1  3.356  4.567
>>> df.applymap(lambda x: len(str(x)))
   0  1
0  3  4
1  5  5

Note that a vectorized version of func often exists, which will be much faster. You could square each number elementwise.

>>> df.applymap(lambda x: x**2)
           0          1
0   1.000000   4.494400
1  11.262736  20.857489

But it’s better to avoid applymap in that case.

>>> df ** 2
           0          1
0   1.000000   4.494400
1  11.262736  20.857489

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Licensed under the 3-clause BSD License.
https://pandas.pydata.org/pandas-docs/version/0.23.4/generated/pandas.DataFrame.applymap.html