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lapack/testlapack: add implementation comments to Dlanst test

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This commit is contained in:
Vladimir Chalupecky
2018-11-28 17:30:59 +01:00
committed by Vladimír Chalupecký
parent 3ff63b0dd5
commit 8ebfea9f67
1 changed files with 8 additions and 0 deletions
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8
lapack/testlapack/dlanst.go
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@@ -23,15 +23,19 @@ func DlanstTest(t *testing.T, impl Dlanster) {
for _, norm := range []lapack.MatrixNorm{lapack.MaxAbs, lapack.MaxColumnSum, lapack.MaxRowSum, lapack.Frobenius} { for _, norm := range []lapack.MatrixNorm{lapack.MaxAbs, lapack.MaxColumnSum, lapack.MaxRowSum, lapack.Frobenius} {
for _, n := range []int{1, 3, 10, 100} { for _, n := range []int{1, 3, 10, 100} {
for cas := 0; cas < 100; cas++ { for cas := 0; cas < 100; cas++ {
// Generate randomly the main diagonal of the
// symmetric tridiagonal matrix A.
d := make([]float64, n) d := make([]float64, n)
for i := range d { for i := range d {
d[i] = rnd.NormFloat64() d[i] = rnd.NormFloat64()
} }
// Generate randomly the off-diagonal of A.
e := make([]float64, n-1) e := make([]float64, n-1)
for i := range e { for i := range e {
e[i] = rnd.NormFloat64() e[i] = rnd.NormFloat64()
} }
// Create A in dense representation.
m := n m := n
lda := n lda := n
a := make([]float64, m*lda) a := make([]float64, m*lda)
@@ -42,8 +46,12 @@ func DlanstTest(t *testing.T, impl Dlanster) {
a[i*lda+i+1] = e[i] a[i*lda+i+1] = e[i]
a[(i+1)*lda+i] = e[i] a[(i+1)*lda+i] = e[i]
} }
work := make([]float64, n) work := make([]float64, n)
// Compute a norm of A using Dlanst.
syNorm := impl.Dlanst(norm, n, d, e) syNorm := impl.Dlanst(norm, n, d, e)
// Compute a reference value for the norm using
// Dlange and the dense representation of A.
geNorm := impl.Dlange(norm, m, n, a, lda, work) geNorm := impl.Dlange(norm, m, n, a, lda, work)
if math.Abs(syNorm-geNorm) > 1e-12 { if math.Abs(syNorm-geNorm) > 1e-12 {
t.Errorf("Norm mismatch: norm = %v, cas = %v, n = %v. Want %v, got %v.", string(norm), cas, n, geNorm, syNorm) t.Errorf("Norm mismatch: norm = %v, cas = %v, n = %v. Want %v, got %v.", string(norm), cas, n, geNorm, syNorm)