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)
alpha = 2/(period + 1) and
field(t) is the current value of a field.
trendline ( <trendtype><period>"("<field>")" [AS <newfield>] )...
- 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).
- Syntax: <num>
- Description: The period over which to compute the trend, an integer between 2 and 10000.
- Syntax: "("<field>")"
- Description: The name of the field on which to calculate the trend.
- Syntax: <field>
- Description: Specify a new field name to write the output to.
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
Have questions? Visit Splunk Answers and see what questions and answers the Splunk community has using the trendline command.
This documentation applies to the following versions of Splunk Cloud™: 6.6.3, 7.0.0, 7.0.2, 7.0.3