Momentum (MOM)
A simple indicator that measures the amount that a security's price has changed over a given span of time.
Visual Example

Synthetic ideal per library logic. Generated 2026-06-25 IST via docs/generate_all_previews.py (reproducible; maps to core Next<T> implementation).
Description
The Momentum (MOM) indicator is a technical analysis tool that a simple indicator that measures the amount that a security's price has changed over a given span of time.
This indicator is primarily used for identifying key market conditions. It provides a robust signal that can be easily integrated into both simple strategies and more complex machine learning feature pipelines. Compared to its alternatives, it offers a distinct balance of responsiveness and stability.
Traders often combine this with other metrics to confirm signals and avoid false positives during sideways market regimes. It remains a standard tool for systematic trading models.
Use to measure the velocity of price changes. Positive values indicate an uptrend, while negative values indicate a downtrend.
Momentum is one of the most basic and powerful concepts in technical analysis. It measures the rate of change of an asset's price, providing a clear indication of trend strength and potential exhaustion before the actual price reversal occurs. — StockCharts ChartSchool
QuantWave implements this indicator via the universal Next<T> trait, guaranteeing bit-identical results between Rust streaming, Python streaming, and Polars batch (.ta() / map_batches) surfaces.
Formula / Specification
Implementation (quantwave-core/src/indicators/momentum.rs):
Gold-standard parity vectors: quantwave-core/tests/gold_standard/mom.json.
Parameters
| Parameter | Default | Description |
|---|---|---|
timeperiod |
10 | Lookback period |
Usage Examples
Streaming (Rust)
use quantwave_core::indicators::MOM;
use quantwave_core::traits::Next;
let mut ind = MOM::new(10);
for price in &prices {
let value = ind.next(price);
}
Streaming (Python)
Polars Batch (Python)
import polars as pl
df = (
pl.read_csv('ohlcv.csv')
.lazy()
.with_columns(
pl.col("close").ta.mom(10).alias("momentum_mom")
)
.collect()
)
All surfaces are bit-identical via the single Next<T> implementation and proptests.
Edge Cases & Limitations
- Warm-up: first
10bars 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/m/momentum.asp
Implementation: quantwave-core/src/indicators/momentum.rs (MOM / MOM_METADATA).
Parity: quantwave-core/tests/gold_standard/mom.json
Provenance: Standards bulk upgrade 2026-06-25 IST — see docs/DOCUMENTATION_STANDARDS.md.