polars.Expr.count#
- Expr.count() Expr [source]#
Return the number of non-null elements in the column.
- Returns:
- Expr
Expression of data type
UInt32
.
See also
Examples
>>> df = pl.DataFrame({"a": [1, 2, 3], "b": [None, 4, 4]}) >>> df.select(pl.all().count()) shape: (1, 2) ┌─────┬─────┐ │ a ┆ b │ │ --- ┆ --- │ │ u32 ┆ u32 │ ╞═════╪═════╡ │ 3 ┆ 2 │ └─────┴─────┘