polars.LazyFrame.inspect

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

Inspect a node in the computation graph.

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

Examples

>>> lf = pl.LazyFrame({"foo": [1, 1, -2, 3]})
>>> (
...     lf.select(pl.col("foo").cumsum().alias("bar"))
...     .inspect()  # print the node before the filter
...     .filter(pl.col("bar") == pl.col("foo"))
... )  
<LazyFrame [1 col, {"bar": Int64}] at ...>