zeonta.aroon() — How recently price made a new high vs. a new low, as a 0-100 pair.
What it measures
Where donchian marks where the n-bar high and low currently sit in price terms, Aroon marks how long ago they happened. A fresh high scores Aroon-Up at 100 no matter how far away it is in price; a high from n bars back scores 0 even if price is still sitting right next to it — the whole indicator is about recency, not level.
Formula
Aroon-Up = ((n - DaysSinceHighestHigh) / n) x 100; Aroon-Down = ((n - DaysSinceLowestLow) / n) x 100; Aroon Oscillator = Aroon-Up - Aroon-Down
Parameters
Required inputs: high, low
| Parameter | Default |
|---|---|
length |
25 |
Returns
| Column |
|---|
AROONU_25 |
AROOND_25 |
AROONOSC_25 |
Usage
Examples run against the 300-bar OHLCV fixture in tests/data/ohlcv.csv, loaded as df. The output shown is the real output.
import pandas as pd
import zeonta
df = pd.read_csv('tests/data/ohlcv.csv', parse_dates=['date']).set_index('date')
zeonta.aroon(df['high'], df['low']).tail(3)
AROONU_25 AROOND_25 AROONOSC_25
date
2024-10-25 64.0 92.0 -28.0
2024-10-26 60.0 88.0 -28.0
2024-10-27 56.0 100.0 -44.0
Accessor form: df.zta.aroon(...)
How to read it
Aroon-Up above 70 with Aroon-Down below 30 signals a strong uptrend (highs keep getting made, lows are stale); the mirror image signals a downtrend. The Aroon Oscillator condenses both into one line around zero: sustained positive readings mark an uptrend bias, sustained negative ones a downtrend bias.
Pitfalls
Aroon-Up and Aroon-Down can both be high or both be low at once (a choppy market can make fresh highs and fresh lows in the same window), which the oscillator alone hides by netting them against each other — check the two raw lines, not just the oscillator, before concluding there is no trend. Ties for the extreme value within the window are broken toward the most recent occurrence, per the source’s own convention.
Reference
Formula source: https://chartschool.stockcharts.com/table-of-contents/technical-indicators-and-overlays/technical-indicators/aroon