pandas.Series.str.count — pandas 3.0.0.dev0+2106.gb2b2d04e41 documentation (original) (raw)
Series.str.count(pat, flags=0)[source]#
Count occurrences of pattern in each string of the Series/Index.
This function is used to count the number of times a particular regex pattern is repeated in each of the string elements of theSeries.
Parameters:
patstr
Valid regular expression.
flagsint, default 0, meaning no flags
Flags for the re module. For a complete list, see here.
Returns:
Series or Index
Same type as the calling object containing the integer counts.
See also
Standard library module for regular expressions.
Standard library version, without regular expression support.
Notes
Some characters need to be escaped when passing in pat. eg. '$'
has a special meaning in regex and must be escaped when finding this literal character.
Examples
s = pd.Series(["A", "B", "Aaba", "Baca", np.nan, "CABA", "cat"]) s.str.count("a") 0 0.0 1 0.0 2 2.0 3 2.0 4 NaN 5 0.0 6 1.0 dtype: float64
Escape '$'
to find the literal dollar sign.
s = pd.Series(["$", "B", "Aab$", "$$ca", "C$B$", "cat"]) s.str.count("\$") 0 1 1 0 2 1 3 2 4 2 5 0 dtype: int64
This is also available on Index
pd.Index(["A", "A", "Aaba", "cat"]).str.count("a") Index([0, 0, 2, 1], dtype='int64')