func showLU(a *mat64.Dense) {
fmt.Printf("a: %v\n\n", mat64.Formatted(a, mat64.Prefix(" ")))
var lu mat64.LU
lu.Factorize(a)
var l, u mat64.TriDense
l.LFrom(&lu)
u.UFrom(&lu)
fmt.Printf("l: %.5f\n\n", mat64.Formatted(&l, mat64.Prefix(" ")))
fmt.Printf("u: %.5f\n\n", mat64.Formatted(&u, mat64.Prefix(" ")))
fmt.Println("p:", lu.Pivot(nil))
}
