polars unpivot

For dataframe.

warning This command requires a plugin The polars unpivot command resides in the polars plugin. To use this command, you must install and register nu_plugin_polars. See the Plugins chapter in the book for more information.

Command Type

plugin

Signature

> polars unpivot {flags}

Flags

• --index, -i {list<any>}: Column names for unpivoting.
• --on, -o {list<any>}: Column names used as value columns.
• --variable-name, -r {string}: Optional name for variable column.
• --value-name, -l {string}: Optional name for value column.

Input/output types:

Examples

unpivot on an eager dataframe

> [[a b c d]; [x 1 4 a] [y 2 5 b] [z 3 6 c]] | polars into-df | polars unpivot -i [b c] -o [a d]
╭───┬───┬───┬──────────┬───────╮
│ # │ b │ c │ variable │ value │
├───┼───┼───┼──────────┼───────┤
│ 0 │ 1 │ 4 │ a        │ x     │
│ 1 │ 2 │ 5 │ a        │ y     │
│ 2 │ 3 │ 6 │ a        │ z     │
│ 3 │ 1 │ 4 │ d        │ a     │
│ 4 │ 2 │ 5 │ d        │ b     │
│ 5 │ 3 │ 6 │ d        │ c     │
╰───┴───┴───┴──────────┴───────╯

unpivot on a lazy dataframe

> [[a b c d]; [x 1 4 a] [y 2 5 b] [z 3 6 c]] | polars into-lazy | polars unpivot -i [b c] -o [a d] | polars collect
╭───┬───┬───┬──────────┬───────╮
│ # │ b │ c │ variable │ value │
├───┼───┼───┼──────────┼───────┤
│ 0 │ 1 │ 4 │ a        │ x     │
│ 1 │ 2 │ 5 │ a        │ y     │
│ 2 │ 3 │ 6 │ a        │ z     │
│ 3 │ 1 │ 4 │ d        │ a     │
│ 4 │ 2 │ 5 │ d        │ b     │
│ 5 │ 3 │ 6 │ d        │ c     │
╰───┴───┴───┴──────────┴───────╯

Ported from nushell/nushell.github.io. Copyright (c) 2021 Nushell Project. MIT License.