DataFrameComparison.left_only

DataFrameComparison.left_only(

*,

lazy: Literal[True],

) → LazyFrame

DataFrameComparison.left_only(

*,

lazy: Literal[False] = False,

) → DataFrame

The rows in the left data frame which cannot be joined with a row in the right data frame.

Parameters:

lazy – If True, return a lazy frame. Otherwise, return an eager frame (default).

Returns:

A data frame or lazy frame containing the rows that are only in the left data frame.

Examples

>>> import polars as pl
>>> from diffly import compare_frames
>>> left = pl.DataFrame({"id": [1, 2, 3, 4], "value": [10.0, 20.0, 30.0, 40.0]})
>>> right = pl.DataFrame({"id": [1, 2, 3, 5], "value": [10.0, 25.0, 30.0, 50.0]})
>>> comparison = compare_frames(left, right, primary_key="id")
>>> comparison.left_only()
shape: (1, 2)
┌─────┬───────┐
│ id  ┆ value │
│ --- ┆ ---   │
│ i64 ┆ f64   │
╞═════╪═══════╡
│ 4   ┆ 40.0  │
└─────┴───────┘