mutate

pydiverse.transform.mutate(**kwargs: ColExpr) → Pipeable

Adds new columns to the table.

Parameters:

kwargs – Each key is the name of a new column, and its value is the column expression defining the new column.

Examples

>>> t1 = pdt.Table(
...     dict(a=[3, 1, 4, 1, 5, 9], b=[2.465, 0.22, -4.477, 10.8, -81.2, 0.0])
... )
>>> t1 >> mutate(u=t1.a * t1.b) >> show()
shape: (6, 3)
┌─────┬────────┬─────────┐
│ a   ┆ b      ┆ u       │
│ --- ┆ ---    ┆ ---     │
│ i64 ┆ f64    ┆ f64     │
╞═════╪════════╪═════════╡
│ 3   ┆ 2.465  ┆ 7.395   │
│ 1   ┆ 0.22   ┆ 0.22    │
│ 4   ┆ -4.477 ┆ -17.908 │
│ 1   ┆ 10.8   ┆ 10.8    │
│ 5   ┆ -81.2  ┆ -406.0  │
│ 9   ┆ 0.0    ┆ 0.0     │
└─────┴────────┴─────────┘