Momentum indicators
Relative Strength Index
Momentum oscillator that compares recent gains and losses.
- Engine
- TA-Lib
- Function
RSI- Input series
- close
- Outputs
- 1
How it works
RSI compares the magnitude of recent upward and downward close changes over the configured period and returns an oscillator value. TA-Lib marks RSI as having an unstable period.
Use case
Use RSI as a normalized momentum feature for detecting stretched or weakening price movement in a dataset.
Parameters
| Parameter | Type | Default | Bounds or options | Description |
|---|---|---|---|---|
| Time Period | integer | 14 | 2…100000 | Number of bars used to compare recent gains and losses. |
Outputs
| Output | Type | Description |
|---|---|---|
| RSI | number | Relative Strength Index value for the bar. |
Reading the result
RSI summarizes the balance of recent upward and downward closes on a bounded scale. High and low regions describe persistent directional pressure over the configured horizon; they do not prove that price must reverse next.
The same level can mean different things in a range, a strong trend, or a market with frequent gaps. Use changes, persistence, and regime context rather than relying on one universal threshold.
Common mistakes
- Treating overbought as an automatic short signal or oversold as an automatic long signal.
- Comparing RSI from different source histories before warmup has stabilized.
- Ignoring timeframe: the same period count represents different elapsed time on different bars.
- Converting warmup or unavailable values to a neutral midpoint without recording that transformation.
DataCat workflow notes
For ML features, the continuous value, distance from a chosen threshold, and recent change can be more informative than a single Boolean flag. Preserve the output quality state alongside any downstream transformation.