How To Compute Relative Strength Index (RSI) using Java?

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public class RSI {
    
    public static double calculateRSI(double[] prices, int period) {
        double[] changes = new double[prices.length - 1];
        double[] gains = new double[prices.length - 1];
        double[] losses = new double[prices.length - 1];
        
        for (int i = 0; i < prices.length - 1; i++) {
            changes[i] = prices[i + 1] - prices[i];
            if (changes[i] >= 0) {
                gains[i] = changes[i];
            } else {
                losses[i] = Math.abs(changes[i]);
            }
        }
        
        double avgGain = calculateAverage(gains, period);
        double avgLoss = calculateAverage(losses, period);
        
        double rs = (avgGain / avgLoss);
        
        return 100 - (100 / (1 + rs));
    }
    
    private static double calculateAverage(double[] values, int period) {
        double sum = 0;
        for (int i = 0; i < period; i++) {
            sum += values[i];
        }
        
        return sum / period;
    }
    
    public static void main(String[] args) {
        double[] prices = {10.4, 11.6, 12.5, 13.3, 12.8, 12.9, 12.4, 13.6, 14.2, 13.8};
        int period = 14;
        
        double rsi = calculateRSI(prices, period);
        System.out.println("RSI: " + rsi);
    }
}