blob: 85a277cd882323efc33a22391c2228a602fe2148 [file] [log] [blame]
// Copyright ©2016 The Gonum Authors. All rights reserved.
// Use of this source code is governed by a BSD-style
// license that can be found in the LICENSE file.
package testlapack
import (
"fmt"
"testing"
"golang.org/x/exp/rand"
"gonum.org/v1/gonum/blas"
"gonum.org/v1/gonum/blas/blas64"
)
type Dlarfxer interface {
Dlarfx(side blas.Side, m, n int, v []float64, tau float64, c []float64, ldc int, work []float64)
}
func DlarfxTest(t *testing.T, impl Dlarfxer) {
rnd := rand.New(rand.NewSource(1))
for _, side := range []blas.Side{blas.Right, blas.Left} {
// For m and n greater than 10 we are testing Dlarf, so avoid unnecessary work.
for m := 1; m < 12; m++ {
for n := 1; n < 12; n++ {
for _, extra := range []int{0, 1, 11} {
for cas := 0; cas < 10; cas++ {
testDlarfx(t, impl, side, m, n, extra, rnd)
}
}
}
}
}
}
func testDlarfx(t *testing.T, impl Dlarfxer, side blas.Side, m, n, extra int, rnd *rand.Rand) {
const tol = 1e-13
// Generate random input data.
var v []float64
if side == blas.Left {
v = randomSlice(m, rnd)
} else {
v = randomSlice(n, rnd)
}
tau := rnd.NormFloat64()
ldc := n + extra
c := randomGeneral(m, n, ldc, rnd)
// Compute the matrix H explicitly as H := I - tau * v * vᵀ.
var h blas64.General
if side == blas.Left {
h = eye(m, m+extra)
} else {
h = eye(n, n+extra)
}
blas64.Ger(-tau, blas64.Vector{Inc: 1, Data: v}, blas64.Vector{Inc: 1, Data: v}, h)
// Compute the product H * C or C * H explicitly.
cWant := nanGeneral(m, n, ldc)
if side == blas.Left {
blas64.Gemm(blas.NoTrans, blas.NoTrans, 1, h, c, 0, cWant)
} else {
blas64.Gemm(blas.NoTrans, blas.NoTrans, 1, c, h, 0, cWant)
}
var work []float64
if h.Rows > 10 {
// Allocate work only if H has order > 10.
if side == blas.Left {
work = make([]float64, n)
} else {
work = make([]float64, m)
}
}
impl.Dlarfx(side, m, n, v, tau, c.Data, c.Stride, work)
prefix := fmt.Sprintf("Case side=%c, m=%v, n=%v, extra=%v", side, m, n, extra)
// Check any invalid modifications of c.
if !generalOutsideAllNaN(c) {
t.Errorf("%v: out-of-range write to C\n%v", prefix, c.Data)
}
if !equalApproxGeneral(c, cWant, tol) {
t.Errorf("%v: unexpected C\n%v", prefix, c.Data)
}
}