polars filter-with

For [dataframe or lazyframe](/commands/categories/dataframe or lazyframe.md).

Filters dataframe using a mask or expression as reference.

warning This command requires a plugin The polars filter-with 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 filter-with {flags} (mask or expression)

Parameters

mask or expression: Boolean mask used to filter data.

Input/output types:

input	output
polars_dataframe	polars_dataframe
polars_lazyframe	polars_lazyframe

Examples

Filter dataframe using a bool mask

> let mask = ([true false] | polars into-df);
    [[a b]; [1 2] [3 4]] | polars into-df | polars filter-with $mask
╭───┬───┬───╮
│ # │ a │ b │
├───┼───┼───┤
│ 0 │ 1 │ 2 │
╰───┴───┴───╯

Filter dataframe using an expression

> [[a b]; [1 2] [3 4]] | polars into-df | polars filter-with ((polars col a) > 1)
╭───┬───┬───╮
│ # │ a │ b │
├───┼───┼───┤
│ 0 │ 3 │ 4 │
╰───┴───┴───╯

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