/**
* Donchian Channels Indicator
* Channels based on highest high and lowest low over a period
*/
export interface DonchianChannel {
upper: number | null
middle: number | null
lower: number | null
position: 'above' | 'below' | 'inside' | null // Current price position vs channel
}
export function calculateDonchianChannels(
highs: number[],
lows: number[],
period: number = 20
): DonchianChannel {
// Minimum 3 data points required
if (highs.length < 3 || lows.length < 3) {
return {
upper: null,
middle: null,
lower: null,
position: null,
}
}
// Use adaptive period
const effectivePeriod = Math.min(period, highs.length)
// Calculate the most recent channel
const recentHighs = highs.slice(-effectivePeriod)
const recentLows = lows.slice(-effectivePeriod)
const upper = Math.max(...recentHighs)
const lower = Math.min(...recentLows)
const middle = (upper + lower) / 2
return {
upper,
middle,
lower,
position: null, // Will be set by caller with current price
}
}
