polars.Series.rle#

Series.rle() → Series[source]#

Compress the Series data using run-length encoding.

Run-length encoding (RLE) encodes data by storing each run of identical values as a single value and its length.

Returns:

Series: Series of data type Struct with fields lengths of data type Int32 and values of the original data type.

Examples

>>> s = pl.Series("s", [1, 1, 2, 1, None, 1, 3, 3])
>>> s.rle().struct.unnest()
shape: (6, 2)
┌─────────┬────────┐
│ lengths ┆ values │
│ ---     ┆ ---    │
│ i32     ┆ i64    │
╞═════════╪════════╡
│ 2       ┆ 1      │
│ 1       ┆ 2      │
│ 1       ┆ 1      │
│ 1       ┆ null   │
│ 1       ┆ 1      │
│ 2       ┆ 3      │
└─────────┴────────┘