Numpy interop

Polars expressions support NumPy ufuncs. See here for a list on all supported numpy functions.

This means that if a function is not provided by Polars, we can use NumPy and we still have fast columnar operation through the NumPy API.

Example

import polars as pl
import numpy as np

df = pl.DataFrame({"a": [1, 2, 3], "b": [4, 5, 6]})

out = df.select(
    [
        np.log(pl.all()).suffix("_log"),
    ]
)
print(out)

shape: (3, 2)
┌──────────┬──────────┐
│ a_log    ┆ b_log    │
│ ---      ┆ ---      │
│ f64      ┆ f64      │
╞══════════╪══════════╡
│ 0.0      ┆ 1.386294 │
├╌╌╌╌╌╌╌╌╌╌┼╌╌╌╌╌╌╌╌╌╌┤
│ 0.693147 ┆ 1.609438 │
├╌╌╌╌╌╌╌╌╌╌┼╌╌╌╌╌╌╌╌╌╌┤
│ 1.098612 ┆ 1.791759 │
└──────────┴──────────┘

Gotcha's

Read more about the gotcha's here.