polars.Expr.sub

Expr.sub(other: Any) → Self

Method equivalent of subtraction operator expr - other.

Parameters:

other

Numeric literal or expression value.

Examples

>>> df = pl.DataFrame({"x": [0, 1, 2, 3, 4]})
>>> df.with_columns(
...     pl.col("x").sub(2).alias("x-2"),
...     pl.col("x").sub(pl.col("x").cum_sum()).alias("x-expr"),
... )
shape: (5, 3)
┌─────┬─────┬────────┐
│ x   ┆ x-2 ┆ x-expr │
│ --- ┆ --- ┆ ---    │
│ i64 ┆ i64 ┆ i64    │
╞═════╪═════╪════════╡
│ 0   ┆ -2  ┆ 0      │
│ 1   ┆ -1  ┆ 0      │
│ 2   ┆ 0   ┆ -1     │
│ 3   ┆ 1   ┆ -3     │
│ 4   ┆ 2   ┆ -6     │
└─────┴─────┴────────┘