Return the number of elements in the column
Description
Null values are counted in the total.
Usage
<Expr>$len()
Value
A polars expression
Examples
#> shape: (1, 2)
#> ┌─────┬─────┐
#> │ a ┆ b │
#> │ --- ┆ --- │
#> │ u32 ┆ u32 │
#> ╞═════╪═════╡
#> │ 3 ┆ 3 │
#> └─────┴─────┘