---
title: DerivativeNode (Kapacitor TICKscript node)
description: DerivativeNode computes the derivative of a stream or batch. The derivative is computed on a single field and behaves similarly to the InfluxQL derivative function.
note: Auto generated by tickdoc

menu:
  kapacitor_1_4:
    name: DerivativeNode
    identifier: derivative_node
    weight: 70
    parent: TICKscript nodes
---
### Constructor

| Chaining Method | Description |
|:---------|:---------|
| **[derivative](#descr) ( `field` `string`)** | Create a new node that computes the derivative of adjacent points.  |

### Property Methods

| Setters | Description |
|:---|:---|
| **[as](#as) ( `value` `string`)** | The new name of the derivative field. Default is the name of the field used when calculating the derivative.  |
| **[nonNegative](#nonnegative) ( )** | If called the derivative will skip negative results.  |
| **[unit](#unit) ( `value` `time.Duration`)** | The time unit of the resulting derivative value. Default: 1s  |



### Chaining Methods
[Alert](/kapacitor/v1.4/nodes/derivative_node/#alert), [Barrier](/kapacitor/v1.4/nodes/derivative_node/#barrier), [Bottom](/kapacitor/v1.4/nodes/derivative_node/#bottom), [Combine](/kapacitor/v1.4/nodes/derivative_node/#combine), [Count](/kapacitor/v1.4/nodes/derivative_node/#count), [CumulativeSum](/kapacitor/v1.4/nodes/derivative_node/#cumulativesum), [Deadman](/kapacitor/v1.4/nodes/derivative_node/#deadman), [Default](/kapacitor/v1.4/nodes/derivative_node/#default), [Delete](/kapacitor/v1.4/nodes/derivative_node/#delete), [Derivative](/kapacitor/v1.4/nodes/derivative_node/#derivative), [Difference](/kapacitor/v1.4/nodes/derivative_node/#difference), [Distinct](/kapacitor/v1.4/nodes/derivative_node/#distinct), [Ec2Autoscale](/kapacitor/v1.4/nodes/derivative_node/#ec2autoscale), [Elapsed](/kapacitor/v1.4/nodes/derivative_node/#elapsed), [Eval](/kapacitor/v1.4/nodes/derivative_node/#eval), [First](/kapacitor/v1.4/nodes/derivative_node/#first), [Flatten](/kapacitor/v1.4/nodes/derivative_node/#flatten), [GroupBy](/kapacitor/v1.4/nodes/derivative_node/#groupby), [HoltWinters](/kapacitor/v1.4/nodes/derivative_node/#holtwinters), [HoltWintersWithFit](/kapacitor/v1.4/nodes/derivative_node/#holtwinterswithfit), [HttpOut](/kapacitor/v1.4/nodes/derivative_node/#httpout), [HttpPost](/kapacitor/v1.4/nodes/derivative_node/#httppost), [InfluxDBOut](/kapacitor/v1.4/nodes/derivative_node/#influxdbout), [Join](/kapacitor/v1.4/nodes/derivative_node/#join), [K8sAutoscale](/kapacitor/v1.4/nodes/derivative_node/#k8sautoscale), [KapacitorLoopback](/kapacitor/v1.4/nodes/derivative_node/#kapacitorloopback), [Last](/kapacitor/v1.4/nodes/derivative_node/#last), [Log](/kapacitor/v1.4/nodes/derivative_node/#log), [Max](/kapacitor/v1.4/nodes/derivative_node/#max), [Mean](/kapacitor/v1.4/nodes/derivative_node/#mean), [Median](/kapacitor/v1.4/nodes/derivative_node/#median), [Min](/kapacitor/v1.4/nodes/derivative_node/#min), [Mode](/kapacitor/v1.4/nodes/derivative_node/#mode), [MovingAverage](/kapacitor/v1.4/nodes/derivative_node/#movingaverage), [Percentile](/kapacitor/v1.4/nodes/derivative_node/#percentile), [Sample](/kapacitor/v1.4/nodes/derivative_node/#sample), [Shift](/kapacitor/v1.4/nodes/derivative_node/#shift), [Sideload](/kapacitor/v1.4/nodes/derivative_node/#sideload), [Spread](/kapacitor/v1.4/nodes/derivative_node/#spread), [StateCount](/kapacitor/v1.4/nodes/derivative_node/#statecount), [StateDuration](/kapacitor/v1.4/nodes/derivative_node/#stateduration), [Stats](/kapacitor/v1.4/nodes/derivative_node/#stats), [Stddev](/kapacitor/v1.4/nodes/derivative_node/#stddev), [Sum](/kapacitor/v1.4/nodes/derivative_node/#sum), [SwarmAutoscale](/kapacitor/v1.4/nodes/derivative_node/#swarmautoscale), [Top](/kapacitor/v1.4/nodes/derivative_node/#top), [Union](/kapacitor/v1.4/nodes/derivative_node/#union), [Where](/kapacitor/v1.4/nodes/derivative_node/#where), [Window](/kapacitor/v1.4/nodes/derivative_node/#window)
<a id='descr'/><hr/><br/>
### Description

Compute the derivative of a stream or batch.
The derivative is computed on a single field
and behaves similarly to the InfluxQL derivative
function. Kapacitor has its own implementation
of the derivative function, and, as a result, is
not part of the normal InfluxQL functions.

Example:


```javascript
     stream
         |from()
             .measurement('net_rx_packets')
         |derivative('value')
            .unit(1s) // default
            .nonNegative()
         ...
```

Computes the derivative via:
(current - previous ) / ( time_difference / unit)

The derivative is computed for each point, and
because of boundary conditions the first point is
dropped.


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Properties
----------

Property methods modify state on the calling node.
They do not add another node to the pipeline, and always return a reference to the calling node.
Property methods are marked using the `.` operator.


### As

The new name of the derivative field.
Default is the name of the field used
when calculating the derivative.


```javascript
derivative.as(value string)
```

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### NonNegative

If called the derivative will skip negative results.


```javascript
derivative.nonNegative()
```

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### Unit

The time unit of the resulting derivative value.
Default: 1s


```javascript
derivative.unit(value time.Duration)
```

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Chaining Methods
----------------

Chaining methods create a new node in the pipeline as a child of the calling node.
They do not modify the calling node.
Chaining methods are marked using the `|` operator.


### Alert

Create an alert node, which can trigger alerts.


```javascript
derivative|alert()
```

Returns: [AlertNode](/kapacitor/v1.4/nodes/alert_node/)

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### Barrier

Create a new Barrier node that emits a BarrierMessage periodically

One BarrierMessage will be emitted every period duration


```javascript
derivative|barrier()
```

Returns: [BarrierNode](/kapacitor/v1.4/nodes/barrier_node/)

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### Bottom

Select the bottom `num` points for `field` and sort by any extra tags or fields.


```javascript
derivative|bottom(num int64, field string, fieldsAndTags ...string)
```

Returns: [InfluxQLNode](/kapacitor/v1.4/nodes/influx_q_l_node/)

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### Combine

Combine this node with itself. The data is combined on timestamp.


```javascript
derivative|combine(expressions ...ast.LambdaNode)
```

Returns: [CombineNode](/kapacitor/v1.4/nodes/combine_node/)

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### Count

Count the number of points.


```javascript
derivative|count(field string)
```

Returns: [InfluxQLNode](/kapacitor/v1.4/nodes/influx_q_l_node/)

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### CumulativeSum

Compute a cumulative sum of each point that is received.
A point is emitted for every point collected.


```javascript
derivative|cumulativeSum(field string)
```

Returns: [InfluxQLNode](/kapacitor/v1.4/nodes/influx_q_l_node/)

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### Deadman

Helper function for creating an alert on low throughput, a.k.a. deadman's switch.

- Threshold -- trigger alert if throughput drops below threshold in points/interval.
- Interval -- how often to check the throughput.
- Expressions -- optional list of expressions to also evaluate. Useful for time of day alerting.

Example:


```javascript
    var data = stream
        |from()...
    // Trigger critical alert if the throughput drops below 100 points per 10s and checked every 10s.
    data
        |deadman(100.0, 10s)
    //Do normal processing of data
    data...
```

The above is equivalent to this
Example:


```javascript
    var data = stream
        |from()...
    // Trigger critical alert if the throughput drops below 100 points per 10s and checked every 10s.
    data
        |stats(10s)
            .align()
        |derivative('emitted')
            .unit(10s)
            .nonNegative()
        |alert()
            .id('node \'stream0\' in task \'{{ .TaskName }}\'')
            .message('{{ .ID }} is {{ if eq .Level "OK" }}alive{{ else }}dead{{ end }}: {{ index .Fields "emitted" | printf "%0.3f" }} points/10s.')
            .crit(lambda: "emitted" <= 100.0)
    //Do normal processing of data
    data...
```

The `id` and `message` alert properties can be configured globally via the 'deadman' configuration section.

Since the [AlertNode](/kapacitor/v1.4/nodes/alert_node/) is the last piece it can be further modified as usual.
Example:


```javascript
    var data = stream
        |from()...
    // Trigger critical alert if the throughput drops below 100 points per 10s and checked every 10s.
    data
        |deadman(100.0, 10s)
            .slack()
            .channel('#dead_tasks')
    //Do normal processing of data
    data...
```

You can specify additional lambda expressions to further constrain when the deadman's switch is triggered.
Example:


```javascript
    var data = stream
        |from()...
    // Trigger critical alert if the throughput drops below 100 points per 10s and checked every 10s.
    // Only trigger the alert if the time of day is between 8am-5pm.
    data
        |deadman(100.0, 10s, lambda: hour("time") >= 8 AND hour("time") <= 17)
    //Do normal processing of data
    data...
```



```javascript
derivative|deadman(threshold float64, interval time.Duration, expr ...ast.LambdaNode)
```

Returns: [AlertNode](/kapacitor/v1.4/nodes/alert_node/)

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### Default

Create a node that can set defaults for missing tags or fields.


```javascript
derivative|default()
```

Returns: [DefaultNode](/kapacitor/v1.4/nodes/default_node/)

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### Delete

Create a node that can delete tags or fields.


```javascript
derivative|delete()
```

Returns: [DeleteNode](/kapacitor/v1.4/nodes/delete_node/)

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### Derivative

Create a new node that computes the derivative of adjacent points.


```javascript
derivative|derivative(field string)
```

Returns: [DerivativeNode](/kapacitor/v1.4/nodes/derivative_node/)

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### Difference

Compute the difference between points independent of elapsed time.


```javascript
derivative|difference(field string)
```

Returns: [InfluxQLNode](/kapacitor/v1.4/nodes/influx_q_l_node/)

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### Distinct

Produce batch of only the distinct points.


```javascript
derivative|distinct(field string)
```

Returns: [InfluxQLNode](/kapacitor/v1.4/nodes/influx_q_l_node/)

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### Ec2Autoscale

Create a node that can trigger autoscale events for a ec2 autoscalegroup.


```javascript
derivative|ec2Autoscale()
```

Returns: [Ec2AutoscaleNode](/kapacitor/v1.4/nodes/ec2_autoscale_node/)

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### Elapsed

Compute the elapsed time between points


```javascript
derivative|elapsed(field string, unit time.Duration)
```

Returns: [InfluxQLNode](/kapacitor/v1.4/nodes/influx_q_l_node/)

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### Eval

Create an eval node that will evaluate the given transformation function to each data point.
A list of expressions may be provided and will be evaluated in the order they are given.
The results are available to later expressions.


```javascript
derivative|eval(expressions ...ast.LambdaNode)
```

Returns: [EvalNode](/kapacitor/v1.4/nodes/eval_node/)

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### First

Select the first point.


```javascript
derivative|first(field string)
```

Returns: [InfluxQLNode](/kapacitor/v1.4/nodes/influx_q_l_node/)

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### Flatten

Flatten points with similar times into a single point.


```javascript
derivative|flatten()
```

Returns: [FlattenNode](/kapacitor/v1.4/nodes/flatten_node/)

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### GroupBy

Group the data by a set of tags.

Can pass literal * to group by all dimensions.
Example:


```javascript
    |groupBy(*)
```



```javascript
derivative|groupBy(tag ...interface{})
```

Returns: [GroupByNode](/kapacitor/v1.4/nodes/group_by_node/)

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### HoltWinters

Compute the holt-winters (/{{< latest "influxdb" "v1" >}}/query_language/functions/#holt-winters) forecast of a data set.


```javascript
derivative|holtWinters(field string, h int64, m int64, interval time.Duration)
```

Returns: [InfluxQLNode](/kapacitor/v1.4/nodes/influx_q_l_node/)

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### HoltWintersWithFit

Compute the holt-winters (/{{< latest "influxdb" "v1" >}}/query_language/functions/#holt-winters) forecast of a data set.
This method also outputs all the points used to fit the data in addition to the forecasted data.


```javascript
derivative|holtWintersWithFit(field string, h int64, m int64, interval time.Duration)
```

Returns: [InfluxQLNode](/kapacitor/v1.4/nodes/influx_q_l_node/)

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### HttpOut

Create an HTTP output node that caches the most recent data it has received.
The cached data is available at the given endpoint.
The endpoint is the relative path from the API endpoint of the running task.
For example, if the task endpoint is at `/kapacitor/v1/tasks/<task_id>` and endpoint is
`top10`, then the data can be requested from `/kapacitor/v1/tasks/<task_id>/top10`.


```javascript
derivative|httpOut(endpoint string)
```

Returns: [HTTPOutNode](/kapacitor/v1.4/nodes/http_out_node/)

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### HttpPost

Creates an HTTP Post node that POSTS received data to the provided HTTP endpoint.
HttpPost expects 0 or 1 arguments. If 0 arguments are provided, you must specify an
endpoint property method.


```javascript
derivative|httpPost(url ...string)
```

Returns: [HTTPPostNode](/kapacitor/v1.4/nodes/http_post_node/)

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### InfluxDBOut

Create an influxdb output node that will store the incoming data into InfluxDB.


```javascript
derivative|influxDBOut()
```

Returns: [InfluxDBOutNode](/kapacitor/v1.4/nodes/influx_d_b_out_node/)

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### Join

Join this node with other nodes. The data is joined on timestamp.


```javascript
derivative|join(others ...Node)
```

Returns: [JoinNode](/kapacitor/v1.4/nodes/join_node/)

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### K8sAutoscale

Create a node that can trigger autoscale events for a kubernetes cluster.


```javascript
derivative|k8sAutoscale()
```

Returns: [K8sAutoscaleNode](/kapacitor/v1.4/nodes/k8s_autoscale_node/)

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### KapacitorLoopback

Create an kapacitor loopback node that will send data back into Kapacitor as a stream.


```javascript
derivative|kapacitorLoopback()
```

Returns: [KapacitorLoopbackNode](/kapacitor/v1.4/nodes/kapacitor_loopback_node/)

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### Last

Select the last point.


```javascript
derivative|last(field string)
```

Returns: [InfluxQLNode](/kapacitor/v1.4/nodes/influx_q_l_node/)

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### Log

Create a node that logs all data it receives.


```javascript
derivative|log()
```

Returns: [LogNode](/kapacitor/v1.4/nodes/log_node/)

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### Max

Select the maximum point.


```javascript
derivative|max(field string)
```

Returns: [InfluxQLNode](/kapacitor/v1.4/nodes/influx_q_l_node/)

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### Mean

Compute the mean of the data.


```javascript
derivative|mean(field string)
```

Returns: [InfluxQLNode](/kapacitor/v1.4/nodes/influx_q_l_node/)

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### Median

Compute the median of the data. Note, this method is not a selector,
if you want the median point use `.percentile(field, 50.0)`.


```javascript
derivative|median(field string)
```

Returns: [InfluxQLNode](/kapacitor/v1.4/nodes/influx_q_l_node/)

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### Min

Select the minimum point.


```javascript
derivative|min(field string)
```

Returns: [InfluxQLNode](/kapacitor/v1.4/nodes/influx_q_l_node/)

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### Mode

Compute the mode of the data.


```javascript
derivative|mode(field string)
```

Returns: [InfluxQLNode](/kapacitor/v1.4/nodes/influx_q_l_node/)

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### MovingAverage

Compute a moving average of the last window points.
No points are emitted until the window is full.


```javascript
derivative|movingAverage(field string, window int64)
```

Returns: [InfluxQLNode](/kapacitor/v1.4/nodes/influx_q_l_node/)

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### Percentile

Select a point at the given percentile. This is a selector function, no interpolation between points is performed.


```javascript
derivative|percentile(field string, percentile float64)
```

Returns: [InfluxQLNode](/kapacitor/v1.4/nodes/influx_q_l_node/)

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### Sample

Create a new node that samples the incoming points or batches.

One point will be emitted every count or duration specified.


```javascript
derivative|sample(rate interface{})
```

Returns: [SampleNode](/kapacitor/v1.4/nodes/sample_node/)

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### Shift

Create a new node that shifts the incoming points or batches in time.


```javascript
derivative|shift(shift time.Duration)
```

Returns: [ShiftNode](/kapacitor/v1.4/nodes/shift_node/)

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### Sideload

Create a node that can load data from external sources


```javascript
derivative|sideload()
```

Returns: [SideloadNode](/kapacitor/v1.4/nodes/sideload_node/)

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### Spread

Compute the difference between `min` and `max` points.


```javascript
derivative|spread(field string)
```

Returns: [InfluxQLNode](/kapacitor/v1.4/nodes/influx_q_l_node/)

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### StateCount

Create a node that tracks number of consecutive points in a given state.


```javascript
derivative|stateCount(expression ast.LambdaNode)
```

Returns: [StateCountNode](/kapacitor/v1.4/nodes/state_count_node/)

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### StateDuration

Create a node that tracks duration in a given state.


```javascript
derivative|stateDuration(expression ast.LambdaNode)
```

Returns: [StateDurationNode](/kapacitor/v1.4/nodes/state_duration_node/)

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### Stats

Create a new stream of data that contains the internal statistics of the node.
The interval represents how often to emit the statistics based on real time.
This means the interval time is independent of the times of the data points the source node is receiving.


```javascript
derivative|stats(interval time.Duration)
```

Returns: [StatsNode](/kapacitor/v1.4/nodes/stats_node/)

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### Stddev

Compute the standard deviation.


```javascript
derivative|stddev(field string)
```

Returns: [InfluxQLNode](/kapacitor/v1.4/nodes/influx_q_l_node/)

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### Sum

Compute the sum of all values.


```javascript
derivative|sum(field string)
```

Returns: [InfluxQLNode](/kapacitor/v1.4/nodes/influx_q_l_node/)

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### SwarmAutoscale

Create a node that can trigger autoscale events for a docker swarm cluster.


```javascript
derivative|swarmAutoscale()
```

Returns: [SwarmAutoscaleNode](/kapacitor/v1.4/nodes/swarm_autoscale_node/)

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### Top

Select the top `num` points for `field` and sort by any extra tags or fields.


```javascript
derivative|top(num int64, field string, fieldsAndTags ...string)
```

Returns: [InfluxQLNode](/kapacitor/v1.4/nodes/influx_q_l_node/)

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### Union

Perform the union of this node and all other given nodes.


```javascript
derivative|union(node ...Node)
```

Returns: [UnionNode](/kapacitor/v1.4/nodes/union_node/)

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### Where

Create a new node that filters the data stream by a given expression.


```javascript
derivative|where(expression ast.LambdaNode)
```

Returns: [WhereNode](/kapacitor/v1.4/nodes/where_node/)

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### Window

Create a new node that windows the stream by time.

NOTE: Window can only be applied to stream edges.


```javascript
derivative|window()
```

Returns: [WindowNode](/kapacitor/v1.4/nodes/window_node/)

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