pandas.DataFrame.mode

DataFrame.mode(axis=0, numeric_only=False, dropna=True)

Get the mode(s) of each element along the selected axis.

The mode of a set of values is the value that appears most often. It can be multiple values.

Parameters:

axis{0 or ‘index’, 1 or ‘columns’}, default 0

The axis to iterate over while searching for the mode:

• 0 or ‘index’ : get mode of each column

• 1 or ‘columns’ : get mode of each row.

numeric_onlybool, default False

If True, only apply to numeric columns.

dropnabool, default True

Don’t consider counts of NaN/NaT.

Returns:

DataFrame

The modes of each column or row.

See also

Series.mode

Return the highest frequency value in a Series.

Series.value_counts

Return the counts of values in a Series.

Examples

>>> df = pd.DataFrame(
...     [
...         ("bird", 2, 2),
...         ("mammal", 4, np.nan),
...         ("arthropod", 8, 0),
...         ("bird", 2, np.nan),
...     ],
...     index=("falcon", "horse", "spider", "ostrich"),
...     columns=("species", "legs", "wings"),
... )
>>> df
           species  legs  wings
falcon        bird     2    2.0
horse       mammal     4    NaN
spider   arthropod     8    0.0
ostrich       bird     2    NaN

By default, missing values are not considered, and the mode of wings are both 0 and 2. Because the resulting DataFrame has two rows, the second row of species and legs contains NaN.

>>> df.mode()
  species  legs  wings
0    bird   2.0    0.0
1     NaN   NaN    2.0

Setting dropna=False NaN values are considered and they can be the mode (like for wings).

>>> df.mode(dropna=False)
  species  legs  wings
0    bird     2    NaN

Setting numeric_only=True, only the mode of numeric columns is computed, and columns of other types are ignored.

>>> df.mode(numeric_only=True)
   legs  wings
0   2.0    0.0
1   NaN    2.0

To compute the mode over columns and not rows, use the axis parameter:

>>> df.mode(axis="columns", numeric_only=True)
           0    1
falcon   2.0  NaN
horse    4.0  NaN
spider   0.0  8.0
ostrich  2.0  NaN