polars.Series.str.zfill#

Series.str.zfill(length: int | IntoExprColumn) → Series[source]#

Pad the start of the string with zeros until it reaches the given length.

A sign prefix (-) is handled by inserting the padding after the sign character rather than before.

Parameters:

length: Pad the string until it reaches this length. Strings with length equal to or greater than this value are returned as-is.

See also

pad_start

Notes

This method is intended for padding numeric strings. If your data contains non-ASCII characters, use pad_start() instead.

Examples

>>> s = pl.Series([-1, 123, 999999, None])
>>> s.cast(pl.String).str.zfill(4)
shape: (4,)
Series: '' [str]
[
        "-001"
        "0123"
        "999999"
        null
]