fourier transform playground

main.go

package main

import (
	"fmt"
	"math"
	"math/cmplx"
)

func comp(v int) complex128 {
	return complex(float64(v), 0)
}

func dft(x []complex128) []complex128 {
	N := len(x)
	X := make([]complex128, N)
	for k := 0; k < N; k++ {
		X[k] = complex128(0)
		for n := 0; n < N; n++ {
			X[k] += x[n] * cmplx.Exp(-complex(0, 2*math.Pi)/comp(N)*comp(k)*comp(n))
		}
	}
	return X
}

func main() {
	fmt.Println(dft([]complex128{1i, 2i, 3i}))
}