polars.Series.rle

Series.rle() → Series

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 len of data type UInt32 and value 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)
┌─────┬───────┐
│ len ┆ value │
│ --- ┆ ---   │
│ u32 ┆ i64   │
╞═════╪═══════╡
│ 2   ┆ 1     │
│ 1   ┆ 2     │
│ 1   ┆ 1     │
│ 1   ┆ null  │
│ 1   ┆ 1     │
│ 2   ┆ 3     │
└─────┴───────┘