pandas.Series.cummax

Series.cummax(axis=0, skipna=True, *args, **kwargs)

Return cumulative maximum over a Series.

Returns a Series of the same size containing the cumulative maximum.

Parameters:

axis{0 or ‘index’}, default 0

This parameter is unused and defaults to 0.

skipnabool, default True

Exclude NA/null values. If the series is NA, the result is NA.

*args, **kwargs

Additional keywords have no effect but might be accepted for compatibility with NumPy.

Returns:

Series

Return cumulative maximum of Series.

See also

core.window.expanding.Expanding.max

Similar functionality but ignores NaN values.

Series.max

Return the maximum over a Series.

Series.cummin

Return cumulative minimum.

Series.cumsum

Return cumulative sum.

Series.cumprod

Return cumulative product.

Examples

>>> s = pd.Series([2, np.nan, 5, -1, 0])
>>> s
0    2.0
1    NaN
2    5.0
3   -1.0
4    0.0
dtype: float64

By default, NA values are ignored.

>>> s.cummax()
0    2.0
1    NaN
2    5.0
3    5.0
4    5.0
dtype: float64

To include NA values in the operation, use skipna=False

>>> s.cummax(skipna=False)
0    2.0
1    NaN
2    NaN
3    NaN
4    NaN
dtype: float64