Splunk Cloud

Search Reference

Download manual as PDF

Download topic as PDF

trendline

Description

Computes the moving averages of fields: simple moving average (sma), exponential moving average (ema), and weighted moving average (wma) The output is written to a new field, which you can specify.

SMA and WMA both compute a sum over the period of most recent values. WMA puts more weight on recent values rather than past values. EMA is calculated using the following formula.

EMA(t) = alpha * EMA(t-1) + (1 - alpha) * field(t)

where alpha = 2/(period + 1) and field(t) is the current value of a field.

Syntax

trendline ( <trendtype><period>"("<field>")" [AS <newfield>] )...

Required arguments

trendtype
Syntax: syntax = sma | ema | wma
Description: The type of trend to compute. Current supported trend types include simple moving average (sma), exponential moving average (ema), and weighted moving average (wma).
period
Syntax: <num>
Description: The period over which to compute the trend, an integer between 2 and 10000.
<field>
Syntax: "("<field>")"
Description: The name of the field on which to calculate the trend.

Optional arguments

<newfield>
Syntax: <field>
Description: Specify a new field name to write the output to.
Default: <trendtype><period>(<field>)

Examples

Example 1: Computes a five event simple moving average for field 'foo' and writes the result to new field called 'smoothed_foo.' Also, in the same line, computes ten event exponential moving average for field 'bar'. Because no AS clause is specified, writes the result to the field 'ema10(bar)'.

... | trendline sma5(foo) AS smoothed_foo ema10(bar)

Example 2: Overlay a trendline over a chart of events by month.

index="bar" | stats count BY date_month | trendline sma2(count) AS trend | fields * trend

See also

accum, autoregress, delta, streamstats

Answers

Have questions? Visit Splunk Answers and see what questions and answers the Splunk community has using the trendline command.

PREVIOUS
transpose
  NEXT
tscollect

This documentation applies to the following versions of Splunk Cloud: 6.6.3, 7.0.0, 7.0.2, 7.0.3, 7.0.5, 7.1.3


Comments

Can the trendline be included in an existing chart? I'd like to be able to plot the trandline over a series of raw data points.

Robkelley
August 20, 2012

Was this documentation topic helpful?

Enter your email address, and someone from the documentation team will respond to you:

Please provide your comments here. Ask a question or make a suggestion.

You must be logged into splunk.com in order to post comments. Log in now.

Please try to keep this discussion focused on the content covered in this documentation topic. If you have a more general question about Splunk functionality or are experiencing a difficulty with Splunk, consider posting a question to Splunkbase Answers.

0 out of 1000 Characters