polars.LazyFrame.std#

LazyFrame.std(ddof: int = 1) → Self[source]#

Aggregate the columns in the LazyFrame to their standard deviation 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

>>> lf = pl.LazyFrame(
...     {
...         "a": [1, 2, 3, 4],
...         "b": [1, 2, 1, 1],
...     }
... )
>>> lf.std().collect()
shape: (1, 2)
┌──────────┬─────┐
│ a        ┆ b   │
│ ---      ┆ --- │
│ f64      ┆ f64 │
╞══════════╪═════╡
│ 1.290994 ┆ 0.5 │
└──────────┴─────┘
>>> lf.std(ddof=0).collect()
shape: (1, 2)
┌──────────┬──────────┐
│ a        ┆ b        │
│ ---      ┆ ---      │
│ f64      ┆ f64      │
╞══════════╪══════════╡
│ 1.118034 ┆ 0.433013 │
└──────────┴──────────┘