TRIX
A momentum oscillator that shows the percent rate of change of a triple exponentially smoothed moving average.
Visual Example

Synthetic ideal per library logic. Generated 2026-07-01 IST via docs/generate_all_previews.py (reproducible; maps to core Next<T> implementation).
Description
A momentum oscillator that shows the percent rate of change of a triple exponentially smoothed moving average.
Use to filter out market noise and identify trend reversals. TRIX crossings of the zero line or a signal line can provide trade entries.
Native Rust implementation with gold-standard or TA-Lib parity tests where applicable.
Developed by Jack Hutson in the early 1980s, TRIX is a powerful momentum oscillator that effectively filters out minor price fluctuations. By triple-smoothing an EMA, it emphasizes the underlying trend and provides a clear signal when the trend changes direction. — StockCharts ChartSchool
Typical applications:
- Fade extremes in ranges; trade with trend on recoveries from oversold/overbought
- Use divergences as early warning — confirm with structure or volume
- Parameter default
15— shorten for sensitivity, lengthen for stability - Drop into
build_feature_matrix()for ML research
QuantWave implements this via the universal Next<T> trait — bit-identical across Rust streaming, Python streaming, and Polars .ta() batch plugins.
Formula / Specification
Implementation (quantwave-core/src/indicators/momentum.rs):
Gold-standard parity vectors: quantwave-core/tests/gold_standard/trix.json.
Parameters
| Parameter | Default | Description |
|---|---|---|
timeperiod |
15 | Smoothing period |
Usage Examples
Streaming (Rust)
use quantwave_core::indicators::TRIX;
use quantwave_core::traits::Next;
let mut ind = TRIX::new(15);
for price in &prices {
let value = ind.next(price);
}
Streaming (Python)
Polars Batch (Python)
import polars as pl
import quantwave # registers pl.col().ta
df = (
pl.read_csv('ohlcv.csv')
.lazy()
.with_columns(
pl.col("close").ta.trix(15).alias("trix")
)
.collect()
)
All surfaces are bit-identical via the single Next<T> implementation and proptests.
Edge Cases & Limitations
- Warm-up: first
15bars may return NaN or partial state per implementation. - Parameter sensitivity: smaller periods increase noise; larger periods increase lag.
- Sudden gaps or bad ticks can distort rolling windows — consider pre-filtering.
- Single-series indicators ignore volume unless otherwise documented.
- Validated via proptests against gold-standard vectors where available.
- No look-ahead bias; streaming and Polars batch paths are bit-identical.
Boundary Behavior
| Condition | Behavior |
|---|---|
| Warm-up | Leading bars return NaN until warmup_bars is satisfied. |
| period > len | When period exceeds series length, output is all NaN. |
| NaN inputs | NaN in input propagates to output (NaN out). |
| Invalid params | Non-positive period or missing required params raise ValueError. |
| Empty data | Empty input returns an empty result series. |
Related Indicators & See Also
Sources & References
Primary Source: https://www.investopedia.com/terms/t/trix.asp
Implementation: quantwave-core/src/indicators/momentum.rs (TRIX / TRIX_METADATA).
Parity: quantwave-core/tests/gold_standard/trix.json
Provenance: Standards bulk upgrade 2026-07-01 IST — see docs/DOCUMENTATION_STANDARDS.md.