1 // Copyright ©2016 The Gonum Authors. All rights reserved.
2 // Use of this source code is governed by a BSD-style
3 // license that can be found in the LICENSE file.
11 "golang.org/x/exp/rand"
13 "gonum.org/v1/gonum/blas"
14 "gonum.org/v1/gonum/blas/blas64"
15 "gonum.org/v1/gonum/lapack"
18 type Dgebaker interface {
19 Dgebak(job lapack.Job, side lapack.EVSide, n, ilo, ihi int, scale []float64, m int, v []float64, ldv int)
22 func DgebakTest(t *testing.T, impl Dgebaker) {
23 rnd := rand.New(rand.NewSource(1))
25 for _, job := range []lapack.Job{lapack.None, lapack.Permute, lapack.Scale, lapack.PermuteScale} {
26 for _, side := range []lapack.EVSide{lapack.LeftEV, lapack.RightEV} {
27 for _, n := range []int{0, 1, 2, 3, 4, 5, 6, 10, 18, 31, 53} {
28 for _, extra := range []int{0, 11} {
29 for cas := 0; cas < 100; cas++ {
31 v := randomGeneral(n, m, m+extra, rnd)
35 ilo = rnd.Intn(ihi + 1)
39 testDgebak(t, impl, job, side, ilo, ihi, v, rnd)
47 func testDgebak(t *testing.T, impl Dgebaker, job lapack.Job, side lapack.EVSide, ilo, ihi int, v blas64.General, rnd *rand.Rand) {
51 extra := v.Stride - v.Cols
53 // Create D and D^{-1} by generating random scales between ilo and ihi.
57 if job == lapack.Scale || job == lapack.PermuteScale {
61 for i := ilo; i <= ihi; i++ {
62 scale[i] = 2 * rnd.Float64()
63 d.Data[i*d.Stride+i] = scale[i]
64 dinv.Data[i*dinv.Stride+i] = 1 / scale[i]
69 // Create P by generating random column swaps.
71 if job == lapack.Permute || job == lapack.PermuteScale {
72 // Make up some random permutations.
73 for i := n - 1; i > ihi; i-- {
74 scale[i] = float64(rnd.Intn(i + 1))
76 blas64.Vector{p.Stride, p.Data[i:]},
77 blas64.Vector{p.Stride, p.Data[int(scale[i]):]})
79 for i := 0; i < ilo; i++ {
80 scale[i] = float64(i + rnd.Intn(ihi-i+1))
82 blas64.Vector{p.Stride, p.Data[i:]},
83 blas64.Vector{p.Stride, p.Data[int(scale[i]):]})
87 got := cloneGeneral(v)
88 impl.Dgebak(job, side, n, ilo, ihi, scale, m, got.Data, got.Stride)
90 prefix := fmt.Sprintf("Case job=%v, side=%v, n=%v, ilo=%v, ihi=%v, m=%v, extra=%v",
91 job, side, n, ilo, ihi, m, extra)
93 if !generalOutsideAllNaN(got) {
94 t.Errorf("%v: out-of-range write to V\n%v", prefix, got.Data)
97 // Compute D*V or D^{-1}*V and store into dv.
99 if side == lapack.RightEV {
100 blas64.Gemm(blas.NoTrans, blas.NoTrans, 1, d, v, 0, dv)
102 blas64.Gemm(blas.NoTrans, blas.NoTrans, 1, dinv, v, 0, dv)
104 // Compute P*D*V or P*D^{-1}*V and store into want.
105 want := zeros(n, m, m)
106 blas64.Gemm(blas.NoTrans, blas.NoTrans, 1, p, dv, 0, want)
108 if !equalApproxGeneral(want, got, tol) {
109 t.Errorf("%v: unexpected value of V", prefix)