unfinished benchmark of parallel calculation in Go (trying to rewrite https://habrahabr.ru/post/336684/)

parallel_benchmark.go

package main

import (
	"math"
	"time"
	"fmt"
)

type Point struct {
	x float64
	y float64
	z float64
}

func NewMatrix(xlen, ylen int) [][]float64 {
	m := make([][]float64, xlen)
	for i := 0; i < xlen; i++ {
		m[i] = make([]float64, ylen)
	}
	return m
}

func R(p, q Point) float64 {
	rx := p.x - q.x
	ry := p.y - q.y
	rz := p.z - q.z
	return 1 / (1 + math.Sqrt(rx*rx+ry*ry+rz*rz))
}

func Calculate(P []Point, Q []Point, M [][]float64) {
	c := make(chan bool)

	for i, p := range P {
		for j, q := range Q {
			go func(c chan bool) {
				M[i][j] = R(p, q)
				c <- true
			}(c)
		}
	}

	for i := 0; i < len(P)*len(Q); i++ {
		<-c
	}
}

func main() {
	m := NewMatrix(5000, 5000)
	P := make([]Point, 5000)
	Q := make([]Point, 5000)

	t := time.Now()
	Calculate(P, Q, m)
	fmt.Println(time.Since(t))
}