---
title: StateDurationNode (Kapacitor TICKscript node)
description: StateDurationNode computes the duration of a given state (defined using a lambda expression).
note: Auto generated by tickdoc

menu:
  kapacitor_1_4:
    name: StateDurationNode
    identifier: state_duration_node
    weight: 270
    parent: TICKscript nodes
---
### Constructor

| Chaining Method | Description |
|:---------|:---------|
| **[stateDuration](#descr) ( `expression` `ast.LambdaNode`)** | Create a node that tracks duration in a given state.  |

### Property Methods

| Setters | Description |
|:---|:---|
| **[as](#as) ( `value` `string`)** | The new name of the resulting duration field. Default: 'state_duration'  |
| **[unit](#unit) ( `value` `time.Duration`)** | The time unit of the resulting duration value. Default: 1s.  |



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

Compute the duration of a given state.
The state is defined using a lambda expression. For each consecutive point for
which the expression evaluates as true, the state duration will be
incremented by the duration between points. When a point evaluates as false,
the state duration is reset.

The state duration will be added as an additional field to each point. If the
expression evaluates as false, the value will be `-1`. If the expression
generates an error during evaluation, the point is discarded, and does not
affect the state duration.

Example:


```javascript
     stream
         |from()
             .measurement('cpu')
         |where(lambda: "cpu" == 'cpu-total')
         |groupBy('host')
         |stateDuration(lambda: "usage_idle" <= 10)
             .unit(1m)
         |alert()
             // Warn after 1 minute
             .warn(lambda: "state_duration" >= 1)
             // Critical after 5 minutes
             .crit(lambda: "state_duration" >= 5)
```

Note that as the first point in the given state has no previous point, its
state duration will be 0.


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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 resulting duration field.
Default: 'state_duration'


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

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### Unit

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


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

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

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### Count

Count the number of points.


```javascript
stateDuration|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
stateDuration|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
stateDuration|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
stateDuration|default()
```

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

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### Delete

Create a node that can delete tags or fields.


```javascript
stateDuration|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
stateDuration|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
stateDuration|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
stateDuration|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
stateDuration|ec2Autoscale()
```

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

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### Elapsed

Compute the elapsed time between points


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

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

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### First

Select the first point.


```javascript
stateDuration|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
stateDuration|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
stateDuration|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
stateDuration|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
stateDuration|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
stateDuration|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
stateDuration|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
stateDuration|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
stateDuration|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
stateDuration|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
stateDuration|kapacitorLoopback()
```

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

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### Last

Select the last point.


```javascript
stateDuration|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
stateDuration|log()
```

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

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### Max

Select the maximum point.


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

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

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### Min

Select the minimum point.


```javascript
stateDuration|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
stateDuration|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
stateDuration|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
stateDuration|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
stateDuration|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
stateDuration|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
stateDuration|sideload()
```

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

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### Spread

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


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

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

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### Stddev

Compute the standard deviation.


```javascript
stateDuration|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
stateDuration|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
stateDuration|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
stateDuration|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
stateDuration|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
stateDuration|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
stateDuration|window()
```

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

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