polars.Expr.sum# Expr.sum() → Expr[source]# Get sum value. Notes Dtypes in {Int8, UInt8, Int16, UInt16} are cast to Int64 before summing to prevent overflow issues. Examples >>> df = pl.DataFrame({"a": [-1, 0, 1]}) >>> df.select(pl.col("a").sum()) shape: (1, 1) ┌─────┐ │ a │ │ --- │ │ i64 │ ╞═════╡ │ 0 │ └─────┘