polars.Expr.str.count_match

Expr.str.count_match(pattern: str) → Expr

Count all successive non-overlapping regex matches.

Parameters:

pattern

A valid regular expression pattern, compatible with the regex crate.

Returns:

Expr

Expression of data type UInt32. Contains null values if the original value is null or the regex captures nothing.

Examples

>>> df = pl.DataFrame({"foo": ["123 bla 45 asd", "xyz 678 910t"]})
>>> df.select(
...     pl.col("foo").str.count_match(r"\d").alias("count_digits"),
... )
shape: (2, 1)
┌──────────────┐
│ count_digits │
│ ---          │
│ u32          │
╞══════════════╡
│ 5            │
│ 6            │
└──────────────┘