vendor/gonum.org/v1/gonum/lapack/testlapack/dlansy.go

   1 // Copyright ©2015 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.
   4
   5 package testlapack
   6
   7 import (
   8         "math"
   9         "testing"
  10
  11         "golang.org/x/exp/rand"
  12
  13         "gonum.org/v1/gonum/blas"
  14         "gonum.org/v1/gonum/lapack"
  15 )
  16
  17 type Dlansyer interface {
  18         Dlanger
  19         Dlansy(norm lapack.MatrixNorm, uplo blas.Uplo, n int, a []float64, lda int, work []float64) float64
  20 }
  21
  22 func DlansyTest(t *testing.T, impl Dlansyer) {
  23         rnd := rand.New(rand.NewSource(1))
  24         for _, norm := range []lapack.MatrixNorm{lapack.MaxAbs, lapack.MaxColumnSum, lapack.MaxRowSum, lapack.NormFrob} {
  25                 for _, uplo := range []blas.Uplo{blas.Lower, blas.Upper} {
  26                         for _, test := range []struct {
  27                                 n, lda int
  28                         }{
  29                                 {1, 0},
  30                                 {3, 0},
  31
  32                                 {1, 10},
  33                                 {3, 10},
  34                         } {
  35                                 for trial := 0; trial < 100; trial++ {
  36                                         n := test.n
  37                                         lda := test.lda
  38                                         if lda == 0 {
  39                                                 lda = n
  40                                         }
  41                                         a := make([]float64, lda*n)
  42                                         if trial == 0 {
  43                                                 for i := range a {
  44                                                         a[i] = float64(i)
  45                                                 }
  46                                         } else {
  47                                                 for i := range a {
  48                                                         a[i] = rnd.NormFloat64()
  49                                                 }
  50                                         }
  51
  52                                         aDense := make([]float64, n*n)
  53                                         if uplo == blas.Upper {
  54                                                 for i := 0; i < n; i++ {
  55                                                         for j := i; j < n; j++ {
  56                                                                 v := a[i*lda+j]
  57                                                                 aDense[i*n+j] = v
  58                                                                 aDense[j*n+i] = v
  59                                                         }
  60                                                 }
  61                                         } else {
  62                                                 for i := 0; i < n; i++ {
  63                                                         for j := 0; j <= i; j++ {
  64                                                                 v := a[i*lda+j]
  65                                                                 aDense[i*n+j] = v
  66                                                                 aDense[j*n+i] = v
  67                                                         }
  68                                                 }
  69                                         }
  70                                         work := make([]float64, n)
  71                                         got := impl.Dlansy(norm, uplo, n, a, lda, work)
  72                                         want := impl.Dlange(norm, n, n, aDense, n, work)
  73                                         if math.Abs(want-got) > 1e-14 {
  74                                                 t.Errorf("Norm mismatch. norm = %c, upper = %v, n = %v, lda = %v, want %v, got %v.",
  75                                                         norm, uplo == blas.Upper, n, lda, got, want)
  76                                         }
  77                                 }
  78                         }
  79                 }
  80         }
  81 }