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:
input | output |
---|---|
any | any |
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 │
╰───┴──────────────────╯