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

title	description	menu	weight	flux/v0/tags	introduced
tripleEMA() function	`tripleEMA()` returns the triple exponential moving average (TEMA) of values in the `_value` column.	flux_v0_ref name parent identifier tripleEMA universe universe/tripleEMA	101	transformations	0.38.0

tripleEMA() returns the triple exponential moving average (TEMA) of values in the _value column.

tripleEMA uses n number of points to calculate the TEMA, giving more weight to recent data with less lag than exponentialMovingAverage() and doubleEMA().

Triple exponential moving average rules

• A triple exponential moving average is defined as tripleEMA = (3 * EMA_1) - (3 * EMA_2) + EMA_3.
  • EMA_1 is the exponential moving average of the original data.
  • EMA_2 is the exponential moving average of EMA_1.
  • EMA_3 is the exponential moving average of EMA_2.
• A true triple exponential moving average requires at least requires at least 3 * n - 2 values. If not enough values exist to calculate the TEMA, it returns a NaN value.
• tripleEMA() inherits all exponentialMovingAverage() rules.

Function type signature

(<-tables: stream[{A with _value: B}], n: int) => stream[C] where B: Numeric, C: Record

{{% caption %}} For more information, see Function type signatures. {{% /caption %}}

Parameters

n

({{< req >}}) Number of points to use in the calculation.

tables

Input data. Default is piped-forward data (<-).

Examples

Calculate a three point triple exponential moving average

import "sampledata"

sampledata.int()
    |> tripleEMA(n: 3)

{{< expand-wrapper >}} {{% 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
2021-01-01T00:00:50Z	7.6250000000000036	t1

_time	_value	*tag
2021-01-01T00:00:50Z	4.0729166666666625	t2

{{% /expand %}} {{< /expand-wrapper >}}