docs-v2/content/flux/v0/stdlib/universe/cumulativesum.md

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---
title: cumulativeSum() function
description: >
`cumulativeSum()` computes a running sum for non-null records in a table.
menu:
flux_v0_ref:
name: cumulativeSum
parent: universe
identifier: universe/cumulativeSum
weight: 101
flux/v0/tags: [transformations]
introduced: 0.7.0
---
<!------------------------------------------------------------------------------
IMPORTANT: This page was generated from comments in the Flux source code. Any
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To make updates to this documentation, update the function comments above the
function definition in the Flux source code:
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Contributing to Flux: https://github.com/influxdata/flux#contributing
Fluxdoc syntax: https://github.com/influxdata/flux/blob/master/docs/fluxdoc.md
------------------------------------------------------------------------------->
`cumulativeSum()` computes a running sum for non-null records in a table.
The output table schema will be the same as the input table.
##### Function type signature
```js
(<-tables: stream[A], ?columns: [string]) => stream[B] where A: Record, B: Record
```
{{% caption %}}
For more information, see [Function type signatures](/flux/v0/function-type-signatures/).
{{% /caption %}}
## Parameters
### columns
List of columns to operate on. Default is `["_value"]`.
### tables
Input data. Default is piped-forward data (`<-`).
## Examples
### Return the running total of values in each table
```js
import "sampledata"
sampledata.int()
|> cumulativeSum()
```
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{{% expand "View example input and output" %}}
#### Input data
| _time | _value | *tag |
| -------------------- | ------- | ---- |
| 2021-01-01T00:00:00Z | -2 | t1 |
| 2021-01-01T00:00:10Z | 10 | t1 |
| 2021-01-01T00:00:20Z | 7 | t1 |
| 2021-01-01T00:00:30Z | 17 | t1 |
| 2021-01-01T00:00:40Z | 15 | t1 |
| 2021-01-01T00:00:50Z | 4 | t1 |
| _time | _value | *tag |
| -------------------- | ------- | ---- |
| 2021-01-01T00:00:00Z | 19 | t2 |
| 2021-01-01T00:00:10Z | 4 | t2 |
| 2021-01-01T00:00:20Z | -3 | t2 |
| 2021-01-01T00:00:30Z | 19 | t2 |
| 2021-01-01T00:00:40Z | 13 | t2 |
| 2021-01-01T00:00:50Z | 1 | t2 |
#### Output data
| _time | _value | *tag |
| -------------------- | ------- | ---- |
| 2021-01-01T00:00:00Z | -2 | t1 |
| 2021-01-01T00:00:10Z | 8 | t1 |
| 2021-01-01T00:00:20Z | 15 | t1 |
| 2021-01-01T00:00:30Z | 32 | t1 |
| 2021-01-01T00:00:40Z | 47 | t1 |
| 2021-01-01T00:00:50Z | 51 | t1 |
| _time | _value | *tag |
| -------------------- | ------- | ---- |
| 2021-01-01T00:00:00Z | 19 | t2 |
| 2021-01-01T00:00:10Z | 23 | t2 |
| 2021-01-01T00:00:20Z | 20 | t2 |
| 2021-01-01T00:00:30Z | 39 | t2 |
| 2021-01-01T00:00:40Z | 52 | t2 |
| 2021-01-01T00:00:50Z | 53 | t2 |
{{% /expand %}}
{{< /expand-wrapper >}}