`polars unnest` for dataframe

Decompose struct columns into separate columns for each of their fields. The new columns will be inserted into the dataframe at the location of the struct column.

Signature

> polars unnest {flags} ...rest

Flags

--separator, -s {string}: optional separator to use when creating new column names

Parameters

...rest: columns to unnest

Input/output types:

input	output
polars_dataframe	polars_dataframe
polars_lazyframe	polars_lazyframe

Examples

Unnest a dataframe

> [[id person]; [1 {name: "Bob", age: 36}] [2 {name: "Betty", age: 63}]]
                    | polars into-df -s {id: i64, person: {name: str, age: u8}}
                    | polars unnest person
                    | polars get id name age
                    | polars sort-by id
╭───┬────┬───────┬─────╮
│ # │ id │ name  │ age │
├───┼────┼───────┼─────┤
│ 0 │  1 │ Bob   │  36 │
│ 1 │  2 │ Betty │  63 │
╰───┴────┴───────┴─────╯

Unnest a lazy dataframe

> [[id person]; [1 {name: "Bob", age: 36}] [2 {name: "Betty", age: 63}]]
                    | polars into-df -s {id: i64, person: {name: str, age: u8}}
                    | polars into-lazy
                    | polars unnest person
                    | polars select (polars col id) (polars col name) (polars col age)
                    | polars collect
                    | polars sort-by id
╭───┬────┬───────┬─────╮
│ # │ id │ name  │ age │
├───┼────┼───────┼─────┤
│ 0 │  1 │ Bob   │  36 │
│ 1 │  2 │ Betty │  63 │
╰───┴────┴───────┴─────╯

Unnest with a custom separator