pandas.Series.str.startswith — pandas 2.3.0 documentation (original) (raw)

Series.str.startswith(pat, na=<no_default>)[source]#

Test if the start of each string element matches a pattern.

Equivalent to str.startswith().

Parameters:

patstr or tuple[str, …]

Character sequence or tuple of strings. Regular expressions are not accepted.

nascalar, optional

Object shown if element tested is not a string. The default depends on dtype of the array. For object-dtype, numpy.nan is used. For the nullable StringDtype, pandas.NA is used. For the "str" dtype, False is used.

Returns:

Series or Index of bool

A Series of booleans indicating whether the given pattern matches the start of each string element.

Examples

s = pd.Series(['bat', 'Bear', 'cat', np.nan]) s 0 bat 1 Bear 2 cat 3 NaN dtype: object

s.str.startswith('b') 0 True 1 False 2 False 3 NaN dtype: object

s.str.startswith(('b', 'B')) 0 True 1 True 2 False 3 NaN dtype: object

Specifying na to be False instead of NaN.

s.str.startswith('b', na=False) 0 True 1 False 2 False 3 False dtype: bool