How To Calculate Relative Strength Index (RSI) using Go?

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package main

import (
	"fmt"
	"math"
)

func calculateRSI(prices []float64, period int) []float64 {
	var gains []float64
	var losses []float64
	var avgGain float64
	var avgLoss float64
	var rs []float64
	var rsi []float64

	for i := 1; i < len(prices); i++ {
		change := prices[i] - prices[i-1]
		if change > 0 {
			gains = append(gains, change)
			losses = append(losses, 0)
		} else {
			gains = append(gains, 0)
			losses = append(losses, -change)
		}

		if i >= period {
			if i == period {
				sumGains := 0.0
				sumLosses := 0.0
				for j := 0; j < period; j++ {
					sumGains += gains[j]
					sumLosses += losses[j]
				}
				avgGain = sumGains / float64(period)
				avgLoss = sumLosses / float64(period)
			} else {
				avgGain = ((avgGain * float64(period-1)) + gains[i]) / float64(period)
				avgLoss = ((avgLoss * float64(period-1)) + losses[i]) / float64(period)
			}

			if avgLoss == 0 {
				rs = append(rs, 100)
			} else {
				rs = append(rs, 100 - (100 / (1 + (avgGain / avgLoss)))
			}

			if i >= period+1 {
				rsi = append(rsi, 100 - (100 / (1 + rs[len(rs)-1]))
			}
		}
	}

	return rsi
}

func main() {
	prices := []float64{50, 55, 60, 57, 65, 70, 75, 80, 85, 90}
	period := 14

	rsi := calculateRSI(prices, period)
	
	for i, value := range rsi {
		fmt.Printf("RSI at day %d: %.2f
", i+period+1, value)
	}
}