Improving the Julia microbench for Go

randmatmul.go

package main

import (
        "fmt"
        "math/rand"
        "time"
        "github.com/gonum/matrix/mat64"
        // Switch to cblas for the C implementation of BLAS.
        blas "github.com/gonum/blas/goblas"
)
        
func randMatMul(n int) *mat64.Dense {
        a := mat64.NewDense(n, n, nil)
        b := mat64.NewDense(n, n, nil)
        for i := 0; i < n; i++ {
                for k := 0; k < n; k++ {
                        a.Set(i, k, rand.Float64())
                        b.Set(i, k, rand.Float64())
                }
        }
        r := mat64.NewDense(n, n, nil)
        r.Mul(a, b)
        return  r
}

func main() {
        mat64.Register(blas.Blas{})

        tmin := time.Hour
        for i := 0; i < 5; i++ {
                t := time.Now()
                c := randMatMul(1000)
                if c.At(0, 0) < 0 {
                        panic("Unexpected negative number")
                }
                d := time.Since(t)
                if d < tmin {
                        tmin = d
                }
        }
        fmt.Printf("took %v\n", tmin)
}