polars.LazyFrame.inspect

LazyFrame.inspect(
    fmt: str = '{}',
) → LazyFrame

Inspect a node in the computation graph.

Print the value that this node in the computation graph evaluates to and pass on the value.

engine:In Memory

Examples

>>> lf = pl.LazyFrame({"foo": [1, 1, -2, 3]})
>>> (
...     lf.with_columns(pl.col("foo").cum_sum().alias("bar"))
...     .inspect()  # print the node before the filter
...     .filter(pl.col("bar") == pl.col("foo"))
... )
<LazyFrame at ...>