/**
* Rainbow Moving Average Indicator
* Multiple moving averages with different periods for trend visualization
*/
/**
* Calculate Rainbow Moving Average
* @param prices Array of closing prices
* @param periods Array of periods for each MA (default rainbow periods)
* @returns RainbowMAData object
*/
export function calculateRainbowMA(prices, periods = [2, 3, 4, 5, 6, 7, 8, 9]) {
if (periods.length < 8 || prices.length < Math.max(...periods)) {
return null;
}
// Calculate all MAs
const mas = [];
for (const period of periods) {
const ma = prices.slice(-period).reduce((sum, price) => sum + price, 0) / period;
mas.push(ma);
}
// Extract individual MA values
const [ma2, ma3, ma4, ma5, ma6, ma7, ma8, ma9] = mas;
// Determine alignment (bullish = fast MAs above slow MAs)
let bullishCount = 0;
let bearishCount = 0;
for (let i = 0; i < mas.length - 1; i++) {
if (mas[i] > mas[i + 1]) {
bullishCount++;
}
else if (mas[i] < mas[i + 1]) {
bearishCount++;
}
}
let alignment;
if (bullishCount >= mas.length - 2) {
alignment = 'bullish_alignment';
}
else if (bearishCount >= mas.length - 2) {
alignment = 'bearish_alignment';
}
else {
alignment = 'mixed';
}
// Determine trend based on alignment and price position
let trend = 'neutral';
if (alignment === 'bullish_alignment') {
trend = 'bullish';
// Check for strong bullish (price well above rainbow)
const currentPrice = prices[prices.length - 1];
if (currentPrice > ma2 * 1.02) {
trend = 'strong_bullish';
}
}
else if (alignment === 'bearish_alignment') {
trend = 'bearish';
// Check for strong bearish (price well below rainbow)
const currentPrice = prices[prices.length - 1];
if (currentPrice < ma9 * 0.98) {
trend = 'strong_bearish';
}
}
// Current price position vs rainbow
const currentPrice = prices[prices.length - 1];
const highestMA = Math.max(...mas);
const lowestMA = Math.min(...mas);
let position;
if (currentPrice > highestMA) {
position = 'above_rainbow';
}
else if (currentPrice < lowestMA) {
position = 'below_rainbow';
}
else {
position = 'in_rainbow';
}
// Calculate trend strength
let strength = 50; // Base neutral strength
if (alignment === 'bullish_alignment') {
strength += bullishCount * 5;
if (position === 'above_rainbow')
strength += 20;
}
else if (alignment === 'bearish_alignment') {
strength -= bearishCount * 5;
if (position === 'below_rainbow')
strength -= 20;
}
strength = Math.max(0, Math.min(100, strength));
// Calculate spread between fastest and slowest MA
const spread = ((ma2 - ma9) / ma9) * 100;
// Check for compression (all MAs close together)
const avgMA = mas.reduce((sum, ma) => sum + ma, 0) / mas.length;
const variance = mas.reduce((sum, ma) => sum + Math.pow(ma - avgMA, 2), 0) / mas.length;
const stdDev = Math.sqrt(variance);
const compression = stdDev / avgMA < 0.01; // Less than 1% standard deviation
return {
ma2, ma3, ma4, ma5, ma6, ma7, ma8, ma9,
trend,
alignment,
position,
strength,
spread,
compression
};
}
/**
* Get Rainbow MA signal
* @param rainbow RainbowMAData object
* @returns Trading signal
*/
export function getRainbowMASignal(rainbow) {
const { trend, alignment, position, compression } = rainbow;
// Compression followed by alignment change is a strong signal
if (compression && alignment === 'bullish_alignment') {
return 'buy';
}
else if (compression && alignment === 'bearish_alignment') {
return 'sell';
}
// Strong trend signals
if (trend === 'strong_bullish' && position === 'above_rainbow') {
return 'buy';
}
else if (trend === 'strong_bearish' && position === 'below_rainbow') {
return 'sell';
}
// Moderate trend signals
if (trend === 'bullish' && position === 'above_rainbow') {
return 'buy';
}
else if (trend === 'bearish' && position === 'below_rainbow') {
return 'sell';
}
return 'neutral';
}
/**
* Calculate Rainbow MA slope
* @param rainbow RainbowMAData object
* @returns Average slope of all MAs
*/
export function getRainbowMASlope(rainbow) {
const mas = [rainbow.ma2, rainbow.ma3, rainbow.ma4, rainbow.ma5,
rainbow.ma6, rainbow.ma7, rainbow.ma8, rainbow.ma9];
// Calculate slope using linear regression
let sumX = 0;
let sumY = 0;
let sumXY = 0;
let sumXX = 0;
for (let i = 0; i < mas.length; i++) {
sumX += i;
sumY += mas[i];
sumXY += i * mas[i];
sumXX += i * i;
}
const n = mas.length;
const slope = (n * sumXY - sumX * sumY) / (n * sumXX - sumX * sumX);
return slope;
}
/**
* Check for Rainbow MA fan formation
* @param rainbow RainbowMAData object
* @returns Whether MAs are forming a fan pattern
*/
export function isRainbowMAFan(rainbow) {
const mas = [rainbow.ma2, rainbow.ma3, rainbow.ma4, rainbow.ma5,
rainbow.ma6, rainbow.ma7, rainbow.ma8, rainbow.ma9];
// Check if MAs are roughly parallel (fan formation)
let parallelCount = 0;
const tolerance = 0.005; // 0.5% tolerance
for (let i = 0; i < mas.length - 2; i++) {
const slope1 = mas[i + 1] - mas[i];
const slope2 = mas[i + 2] - mas[i + 1];
if (Math.abs(slope1 - slope2) / Math.abs(slope1) < tolerance) {
parallelCount++;
}
}
return parallelCount >= mas.length - 3; // Most MAs are parallel
}
