polars.Expr.name.to_uppercase#

Expr.name.to_uppercase() Expr[source]#

Make the root column name uppercase.

Notes

This will undo any previous renaming operations on the expression.

Due to implementation constraints, this method can only be called as the last expression in a chain. Only one name operation per expression will work. Consider using .name.map for advanced renaming.

Examples

>>> df = pl.DataFrame(
...     {
...         "ColX": [1, 2, 3],
...         "ColY": ["x", "y", "z"],
...     }
... )
>>> df.with_columns(pl.all().name.to_uppercase())
shape: (3, 4)
┌──────┬──────┬──────┬──────┐
│ ColX ┆ ColY ┆ COLX ┆ COLY │
│ ---  ┆ ---  ┆ ---  ┆ ---  │
│ i64  ┆ str  ┆ i64  ┆ str  │
╞══════╪══════╪══════╪══════╡
│ 1    ┆ x    ┆ 1    ┆ x    │
│ 2    ┆ y    ┆ 2    ┆ y    │
│ 3    ┆ z    ┆ 3    ┆ z    │
└──────┴──────┴──────┴──────┘