polars.Expr.str.strptime#

Expr.str.strptime(datatype: PolarsTemporalType, fmt: str | None = None, strict: bool = True, exact: bool = True, cache: bool = True, tz_aware: bool | NoDefault = _NoDefault.no_default, utc: bool = False) → Expr[source]#

Parse a Utf8 expression to a Date/Datetime/Time type.

Parameters:
datatype

Date | Datetime | Time

fmt

Format to use, refer to the chrono strftime documentation for specification. Example: "%y-%m-%d".

strict

Raise an error if any conversion fails.

exact

  • If True, require an exact format match.

  • If False, allow the format to match anywhere in the target string.

cache

Use a cache of unique, converted dates to apply the datetime conversion.

tz_aware

Parse timezone aware datetimes. This may be automatically toggled by the fmt given.

Deprecated since version 0.16.17: This is now auto-inferred from the given fmt. You can safely drop this argument, it will be removed in a future version.

utc

Parse timezone aware datetimes as UTC. This may be useful if you have data with mixed offsets.

Notes

When parsing a Datetime the column precision will be inferred from the format string, if given, eg: “%F %T%.3f” => Datetime(“ms”). If no fractional second component is found then the default is “us”.

Examples

Dealing with a consistent format:

>>> ts = ["2020-01-01 01:00Z", "2020-01-01 02:00Z"]
>>> pl.Series(ts).str.strptime(pl.Datetime, "%Y-%m-%d %H:%M%#z")
shape: (2,)
Series: '' [datetime[μs, +00:00]]
[
        2020-01-01 01:00:00 +00:00
        2020-01-01 02:00:00 +00:00
]

Dealing with different formats.

>>> s = pl.Series(
...     "date",
...     [
...         "2021-04-22",
...         "2022-01-04 00:00:00",
...         "01/31/22",
...         "Sun Jul  8 00:34:60 2001",
...     ],
... )
>>> s.to_frame().with_columns(
...     pl.col("date")
...     .str.strptime(pl.Date, "%F", strict=False)
...     .fill_null(pl.col("date").str.strptime(pl.Date, "%F %T", strict=False))
...     .fill_null(pl.col("date").str.strptime(pl.Date, "%D", strict=False))
...     .fill_null(pl.col("date").str.strptime(pl.Date, "%c", strict=False))
... )
shape: (4, 1)
┌────────────┐
│ date       │
│ ---        │
│ date       │
╞════════════╡
│ 2021-04-22 │
│ 2022-01-04 │
│ 2022-01-31 │
│ 2001-07-08 │
└────────────┘