| // 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 ( |
| "math/rand" |
| "testing" |
| |
| "gonum.org/v1/gonum/blas" |
| "gonum.org/v1/gonum/blas/blas64" |
| "gonum.org/v1/gonum/floats" |
| ) |
| |
| type Dgeql2er interface { |
| Dgeql2(m, n int, a []float64, lda int, tau, work []float64) |
| } |
| |
| func Dgeql2Test(t *testing.T, impl Dgeql2er) { |
| rnd := rand.New(rand.NewSource(1)) |
| // TODO(btracey): Add tests for m < n. |
| for _, test := range []struct { |
| m, n, lda int |
| }{ |
| {5, 5, 0}, |
| {5, 3, 0}, |
| {5, 4, 0}, |
| } { |
| m := test.m |
| n := test.n |
| lda := test.lda |
| if lda == 0 { |
| lda = n |
| } |
| a := make([]float64, m*lda) |
| for i := range a { |
| a[i] = rnd.NormFloat64() |
| } |
| tau := nanSlice(min(m, n)) |
| work := nanSlice(n) |
| |
| aCopy := make([]float64, len(a)) |
| copy(aCopy, a) |
| impl.Dgeql2(m, n, a, lda, tau, work) |
| |
| k := min(m, n) |
| // Construct Q. |
| q := blas64.General{ |
| Rows: m, |
| Cols: m, |
| Stride: m, |
| Data: make([]float64, m*m), |
| } |
| for i := 0; i < m; i++ { |
| q.Data[i*q.Stride+i] = 1 |
| } |
| for i := 0; i < k; i++ { |
| h := blas64.General{Rows: m, Cols: m, Stride: m, Data: make([]float64, m*m)} |
| for j := 0; j < m; j++ { |
| h.Data[j*h.Stride+j] = 1 |
| } |
| v := blas64.Vector{Inc: 1, Data: make([]float64, m)} |
| v.Data[m-k+i] = 1 |
| for j := 0; j < m-k+i; j++ { |
| v.Data[j] = a[j*lda+n-k+i] |
| } |
| blas64.Ger(-tau[i], v, v, h) |
| qTmp := blas64.General{Rows: q.Rows, Cols: q.Cols, Stride: q.Stride, Data: make([]float64, len(q.Data))} |
| copy(qTmp.Data, q.Data) |
| blas64.Gemm(blas.NoTrans, blas.NoTrans, 1, h, qTmp, 0, q) |
| } |
| if !isOrthonormal(q) { |
| t.Errorf("Q is not orthonormal") |
| } |
| l := blas64.General{ |
| Rows: m, |
| Cols: n, |
| Stride: n, |
| Data: make([]float64, m*n), |
| } |
| if m >= n { |
| for i := m - n; i < m; i++ { |
| for j := 0; j <= min(i-(m-n), n-1); j++ { |
| l.Data[i*l.Stride+j] = a[i*lda+j] |
| } |
| } |
| } else { |
| panic("untested") |
| } |
| ans := blas64.General{Rows: m, Cols: n, Stride: lda, Data: make([]float64, len(a))} |
| copy(ans.Data, a) |
| |
| blas64.Gemm(blas.NoTrans, blas.NoTrans, 1, q, l, 0, ans) |
| if !floats.EqualApprox(ans.Data, aCopy, 1e-10) { |
| t.Errorf("Reconstruction mismatch: m = %v, n = %v", m, n) |
| } |
| } |
| } |