polars cumulative for dataframe

Cumulative calculation for a column or series.

This command requires a plugin

The polars cumulative 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.

Signature

> polars cumulative {flags} (type)

Flags

  • --reverse, -r: Reverse cumulative calculation

Parameters

  • type: rolling operation. Values of min, max, and sum are accepted.

Input/output types:

inputoutput
dataframedataframe
expressionexpression

Examples

Cumulative sum for a column

> [[a]; [1] [2] [3] [4] [5]]
                    | polars into-df
                    | polars select (polars col a | polars cumulative sum | polars as cum_a)
                    | polars collect
╭───┬───────╮
│ # │ cum_a │
├───┼───────┤
│ 0 │     1 │
│ 1 │     3 │
│ 2 │     6 │
│ 3 │    10 │
│ 4 │    15 │
╰───┴───────╯

Cumulative sum for a series

> [1 2 3 4 5] | polars into-df | polars cumulative sum
╭───┬──────────────────╮
│ # │ 0_cumulative_sum │
├───┼──────────────────┤
│ 0 │                1 │
│ 1 │                3 │
│ 2 │                6 │
│ 3 │               10 │
│ 4 │               15 │
╰───┴──────────────────╯

Cumulative sum for a series in reverse order

> [1 2 3 4 5] | polars into-df | polars cumulative sum --reverse
╭───┬──────────────────╮
│ # │ 0_cumulative_sum │
├───┼──────────────────┤
│ 0 │               15 │
│ 1 │               14 │
│ 2 │               12 │
│ 3 │                9 │
│ 4 │                5 │
╰───┴──────────────────╯