Files
2026-02-08 11:20:43 -10:00

33 lines
941 B
Markdown
Vendored

[//]: # (title: cumSum)
<!---IMPORT org.jetbrains.kotlinx.dataframe.samples.api.Analyze-->
Computes the cumulative sum of values in the selected columns.
```text
cumSum(skipNA = true) [ { columns } ]
```
Returns a [`DataFrame`](DataFrame.md) or [`DataColumn`](DataColumn.md) containing the cumulative sum.
See [column selectors](ColumnSelectors.md) for how to select the columns for this operation.
**Parameters:**
* `skipNA` — when `true`, ignores [`NA` values](nanAndNa.md#na) (`null` or `NaN`).
When `false`, all values after first `NA` will be `NaN` (for `Double` and `Float` columns) or `null` (for integer columns).
**Available for:**
* [`DataFrame`](DataFrame.md)
* [`DataColumn`](DataColumn.md)
* [`GroupBy DataFrame`](groupBy.md#transformation) — cumulative sum per every data group
<!---FUN cumSum-->
```kotlin
df.cumSum { weight }
df.weight.cumSum()
df.groupBy { city }.cumSum { weight }.concat()
```
<!---END-->