DataFrameComparison.fraction_same

DataFrameComparison.fraction_same(column: Literal[None] = None, /) → dict[str, float]

DataFrameComparison.fraction_same(column: str, /) → float

Compute the fraction of matching values.

Parameters:

column – The column to compute the fraction of matching values for. If None (default), compute the fraction for all columns.

Returns:

A single float for the fraction or a mapping from column name to fraction, depending on the value of column. The mapping contains all common columns. It is empty in case there are no common (non-primary key) columns.

Examples

>>> import polars as pl
>>> from diffly import compare_frames
>>> left = pl.DataFrame({"id": [1, 2, 3], "status": ["a", "b", "c"], "value": [10.0, 20.0, 30.0]})
>>> right = pl.DataFrame({"id": [1, 2, 3], "status": ["a", "x", "x"], "value": [10.0, 25.0, 30.0]})
>>> comparison = compare_frames(left, right, primary_key="id")
>>> comparison.fraction_same("value")
0.6666666666666666
>>> comparison.fraction_same()
{'status': 0.3333333333333333, 'value': 0.6666666666666666}