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[bytom/vapor.git] / vendor / gonum.org / v1 / gonum / lapack / testlapack / dtrtri.go

diff --git a/vendor/gonum.org/v1/gonum/lapack/testlapack/dtrtri.go b/vendor/gonum.org/v1/gonum/lapack/testlapack/dtrtri.go
new file mode 100644 (file)
index 0000000..71bfc36
--- /dev/null
+++ b/vendor/gonum.org/v1/gonum/lapack/testlapack/dtrtri.go
@@ -0,0 +1,100 @@
+// Copyright ©2015 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"
+       "testing"
+
+       "golang.org/x/exp/rand"
+
+       "gonum.org/v1/gonum/blas"
+       "gonum.org/v1/gonum/blas/blas64"
+)
+
+type Dtrtrier interface {
+       Dtrconer
+       Dtrtri(uplo blas.Uplo, diag blas.Diag, n int, a []float64, lda int) bool
+}
+
+func DtrtriTest(t *testing.T, impl Dtrtrier) {
+       const tol = 1e-10
+       rnd := rand.New(rand.NewSource(1))
+       bi := blas64.Implementation()
+       for _, uplo := range []blas.Uplo{blas.Upper, blas.Lower} {
+               for _, diag := range []blas.Diag{blas.NonUnit, blas.Unit} {
+                       for _, test := range []struct {
+                               n, lda int
+                       }{
+                               {3, 0},
+                               {70, 0},
+                               {200, 0},
+                               {3, 5},
+                               {70, 92},
+                               {200, 205},
+                       } {
+                               n := test.n
+                               lda := test.lda
+                               if lda == 0 {
+                                       lda = n
+                               }
+                               a := make([]float64, n*lda)
+                               for i := range a {
+                                       a[i] = rnd.Float64()
+                               }
+                               for i := 0; i < n; i++ {
+                                       // This keeps the matrices well conditioned.
+                                       a[i*lda+i] += float64(n)
+                               }
+                               aCopy := make([]float64, len(a))
+                               copy(aCopy, a)
+                               impl.Dtrtri(uplo, diag, n, a, lda)
+                               if uplo == blas.Upper {
+                                       for i := 1; i < n; i++ {
+                                               for j := 0; j < i; j++ {
+                                                       aCopy[i*lda+j] = 0
+                                                       a[i*lda+j] = 0
+                                               }
+                                       }
+                               } else {
+                                       for i := 0; i < n; i++ {
+                                               for j := i + 1; j < n; j++ {
+                                                       aCopy[i*lda+j] = 0
+                                                       a[i*lda+j] = 0
+                                               }
+                                       }
+                               }
+                               if diag == blas.Unit {
+                                       for i := 0; i < n; i++ {
+                                               a[i*lda+i] = 1
+                                               aCopy[i*lda+i] = 1
+                                       }
+                               }
+                               ans := make([]float64, len(a))
+                               bi.Dgemm(blas.NoTrans, blas.NoTrans, n, n, n, 1, a, lda, aCopy, lda, 0, ans, lda)
+                               iseye := true
+                               for i := 0; i < n; i++ {
+                                       for j := 0; j < n; j++ {
+                                               if i == j {
+                                                       if math.Abs(ans[i*lda+i]-1) > tol {
+                                                               iseye = false
+                                                               break
+                                                       }
+                                               } else {
+                                                       if math.Abs(ans[i*lda+j]) > tol {
+                                                               iseye = false
+                                                               break
+                                                       }
+                                               }
+                                       }
+                               }
+                               if !iseye {
+                                       t.Errorf("inv(A) * A != I. Upper = %v, unit = %v, n = %v, lda = %v",
+                                               uplo == blas.Upper, diag == blas.Unit, n, lda)
+                               }
+                       }
+               }
+       }
+}