polars.DataFrame.var#
- DataFrame.var(ddof: int = 1) DataFrame [source]#
Aggregate the columns of this DataFrame to their variance value.
- Parameters:
- ddof
“Delta Degrees of Freedom”: the divisor used in the calculation is N - ddof, where N represents the number of elements. By default ddof is 1.
Examples
>>> df = pl.DataFrame( ... { ... "foo": [1, 2, 3], ... "bar": [6, 7, 8], ... "ham": ["a", "b", "c"], ... } ... ) >>> df.var() shape: (1, 3) ┌─────┬─────┬──────┐ │ foo ┆ bar ┆ ham │ │ --- ┆ --- ┆ --- │ │ f64 ┆ f64 ┆ str │ ╞═════╪═════╪══════╡ │ 1.0 ┆ 1.0 ┆ null │ └─────┴─────┴──────┘ >>> df.var(ddof=0) shape: (1, 3) ┌──────────┬──────────┬──────┐ │ foo ┆ bar ┆ ham │ │ --- ┆ --- ┆ --- │ │ f64 ┆ f64 ┆ str │ ╞══════════╪══════════╪══════╡ │ 0.666667 ┆ 0.666667 ┆ null │ └──────────┴──────────┴──────┘