i/polars.exceptions.DuplicateError.html)
    * [ polars.exceptions.InvalidOperationError ](../../api/polars.exceptions.InvalidOperationError.html)
    * [ polars.exceptions.NoDataError ](../../api/polars.exceptions.NoDataError.html)
    * [ polars.exceptions.NoRowsReturnedError ](../../api/polars.exceptions.NoRowsReturnedError.html)
    * [ polars.exceptions.PolarsError ](../../api/polars.exceptions.PolarsError.html)
    * [ polars.exceptions.PolarsPanicError ](../../api/polars.exceptions.PolarsPanicError.html)
    * [ polars.exceptions.RowsError ](../../api/polars.exceptions.RowsError.html)
    * [ polars.exceptions.SchemaError ](../../api/polars.exceptions.SchemaError.html)
    * [ polars.exceptions.SchemaFieldNotFoundError ](../../api/polars.exceptions.SchemaFieldNotFoundError.html)
    * [ polars.exceptions.ShapeError ](../../api/polars.exceptions.ShapeError.html)
    * [ polars.exceptions.StructFieldNotFoundError ](../../api/polars.exceptions.StructFieldNotFoundError.html)
    * [ polars.exceptions.TooManyRowsReturnedError ](../../api/polars.exceptions.TooManyRowsReturnedError.html)

  * [ Testing ](../../testing.html) __
    * [ polars.testing.assert_frame_equal ](../../api/polars.testing.assert_frame_equal.html)
    * [ polars.testing.assert_frame_not_equal ](../../api/polars.testing.assert_frame_not_equal.html)
    * [ polars.testing.assert_series_equal ](../../api/polars.testing.assert_series_equal.html)
    * [ polars.testing.assert_series_not_equal ](../../api/polars.testing.assert_series_not_equal.html)
    * [ polars.testing.parametric.dataframes ](../../api/polars.testing.parametric.dataframes.html)
    * [ polars.testing.parametric.series ](../../api/polars.testing.parametric.series.html)
    * [ polars.testing.parametric.column ](../../api/polars.testing.parametric.column.html)
    * [ polars.testing.parametric.columns ](../../api/polars.testing.parametric.columns.html)
    * [ polars.testing.parametric.create_list_strategy ](../../api/polars.testing.parametric.create_list_strategy.html)
    * [ polars.testing.parametric.load_profile ](../../api/polars.testing.parametric.load_profile.html)
    * [ polars.testing.parametric.set_profile ](../../api/polars.testing.parametric.set_profile.html)

  * [ Metadata ](../../metadata.html) __
    * [ polars.build_info ](../../api/polars.build_info.html)
    * [ polars.get_index_type ](../../api/polars.get_index_type.html)
    * [ polars.show_versions ](../../api/polars.show_versions.html)
    * [ polars.thread_pool_size ](../../api/polars.thread_pool_size.html)
    * [ polars.threadpool_size ](../../api/polars.threadpool_size.html)

  * [ __ ](../../../index.html)
  * [ Python API reference ](../../index.html)
  * __
  * [ Manipulation/selection ](../modify_select.html)
  * polars.LazyF... 

#  polars.LazyFrame.inspect  #

LazyFrame.  inspect  (  _ fmt  :  [ str
](https://docs.python.org/3/library/stdtypes.html#str "\(in Python v3.12\)") =
'{}'  _ )  →  Self  [ [source]  ](https://github.com/pola-
rs/polars/blob/main/py-polars/polars/lazyframe/frame.py#L1079-L1103) #

    

Inspect a node in the computation graph.

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

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 ...>
    

[ __ previous  polars.LazyFrame.head  ](polars.LazyFrame.head.html "previous
page") [ next  polars.LazyFrame.interpolate  __
](polars.LazyFrame.interpolate.html "next page")

__ On this page

  * ` LazyFrame.inspect()  `

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