---
title: tripleExponentialDerivative() function
description: >
  `tripleExponentialDerivative()` returns the triple exponential derivative (TRIX)
  values using `n` points.
menu:
  flux_v0_ref:
    name: tripleExponentialDerivative
    parent: universe
    identifier: universe/tripleExponentialDerivative
weight: 101
flux/v0/tags: [transformations]
introduced: 0.40.0
---

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`tripleExponentialDerivative()` returns the triple exponential derivative (TRIX)
values using `n` points.

Triple exponential derivative, commonly referred to as “[TRIX](https://en.wikipedia.org/wiki/Trix_(technical_analysis)),”
is a momentum indicator and oscillator. A triple exponential derivative uses
the natural logarithm (log) of input data to calculate a triple exponential
moving average over the period of time. The calculation prevents cycles
shorter than the defined period from being considered by the indicator.
`tripleExponentialDerivative()` uses the time between `n` points to define
the period.

Triple exponential derivative oscillates around a zero line.
A positive momentum **oscillator** value indicates an overbought market;
a negative value indicates an oversold market.
A positive momentum **indicator** value indicates increasing momentum;
a negative value indicates decreasing momentum.

#### Triple exponential moving average rules
- A triple exponential derivative is defined as:
    - `TRIX[i] = ((EMA3[i] / EMA3[i - 1]) - 1) * 100`
    - `EMA3 = EMA(EMA(EMA(data)))`
- If there are not enough values to calculate a triple exponential derivative,
  the output `_value` is `NaN`; all other columns are the same as the last
  record of the input table.
- The function behaves the same way as the `exponentialMovingAverage()` function:
    - The function ignores `null` values.
    - The function operates only on the `_value` column.

##### Function type signature

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

{{% caption %}}
For more information, see [Function type signatures](/flux/v0/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 two-point triple exponential derivative

```js
import "sampledata"

sampledata.float()
    |> tripleExponentialDerivative(n: 2)

```