How To Compute Bollinger Bands using Golang?

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package main

import (
	"fmt"
	"math"
)

func calculateSMA(data []float64, period int) []float64 {
	sma := make([]float64, len(data)-period+1)
	for i := period - 1; i < len(data); i++ {
		sum := 0.0
		for j := i - period + 1; j <= i; j++ {
			sum += data[j]
		}
		sma[i-period+1] = sum / float64(period)
	}
	return sma
}

func calculateStandardDeviation(data []float64, period int) []float64 {
	sd := make([]float64, len(data)-period+1)
	for i := period - 1; i < len(data); i++ {
		sum := 0.0
		for j := i - period + 1; j <= i; j++ {
			sum += math.Pow(data[j]-sma[i-period+1], 2)
		}
		sd[i-period+1] = math.Sqrt(sum / float64(period))
	}
	return sd
}

func calculateBollingerBands(data []float64, period int, multiplier float64) (upperBand, lowerBand []float64) {
	sma := calculateSMA(data, period)
	sd := calculateStandardDeviation(data, period)
	upperBand = make([]float64, len(data)-period+1)
	lowerBand = make([]float64, len(data)-period+1)

	for i := period - 1; i < len(data); i++ {
		upperBand[i-period+1] = sma[i-period+1] + multiplier*sd[i-period+1]
		lowerBand[i-period+1] = sma[i-period+1] - multiplier*sd[i-period+1]
	}
	return upperBand, lowerBand
}

func main() {
	data := []float64{10, 12, 15, 14, 16, 18, 20, 17, 15, 13, 12, 10}
	period := 5
	multiplier := 2.0

	upperBand, lowerBand := calculateBollingerBands(data, period, multiplier)
	fmt.Println("Upper Bollinger Band:", upperBand)
	fmt.Println("Lower Bollinger Band:", lowerBand)
}