gonum.org/v1/gonum@v0.14.0/lapack/testlapack/dlagtm.go (about)

     1  // Copyright ©2020 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  	"fmt"
     9  	"testing"
    10  
    11  	"golang.org/x/exp/rand"
    12  
    13  	"gonum.org/v1/gonum/blas"
    14  	"gonum.org/v1/gonum/blas/blas64"
    15  	"gonum.org/v1/gonum/floats"
    16  	"gonum.org/v1/gonum/lapack"
    17  )
    18  
    19  type Dlagtmer interface {
    20  	Dlagtm(trans blas.Transpose, m, n int, alpha float64, dl, d, du []float64, b []float64, ldb int, beta float64, c []float64, ldc int)
    21  }
    22  
    23  func DlagtmTest(t *testing.T, impl Dlagtmer) {
    24  	rnd := rand.New(rand.NewSource(1))
    25  	for _, trans := range []blas.Transpose{blas.NoTrans, blas.Trans, blas.ConjTrans} {
    26  		t.Run(transToString(trans), func(t *testing.T) {
    27  			for _, m := range []int{0, 1, 2, 3, 4, 5, 10} {
    28  				for _, n := range []int{0, 1, 2, 3, 4, 5, 10} {
    29  					for _, ldb := range []int{max(1, n), n + 3} {
    30  						for _, ldc := range []int{max(1, n), n + 4} {
    31  							for _, alpha := range []float64{0, 1, rnd.NormFloat64()} {
    32  								for _, beta := range []float64{0, 1, rnd.NormFloat64()} {
    33  									dlagtmTest(t, impl, rnd, trans, m, n, ldb, ldc, alpha, beta)
    34  								}
    35  							}
    36  						}
    37  					}
    38  				}
    39  			}
    40  		})
    41  	}
    42  }
    43  
    44  func dlagtmTest(t *testing.T, impl Dlagtmer, rnd *rand.Rand, trans blas.Transpose, m, n int, ldb, ldc int, alpha, beta float64) {
    45  	const (
    46  		tol   = 1e-14
    47  		extra = 10
    48  	)
    49  
    50  	name := fmt.Sprintf("Case m=%v,n=%v,ldb=%v,ldc=%v,alpha=%v,beta=%v", m, n, ldb, ldc, alpha, beta)
    51  
    52  	// Generate three random diagonals.
    53  	dl := randomSlice(n+extra, rnd)
    54  	dlCopy := make([]float64, len(dl))
    55  	copy(dlCopy, dl)
    56  
    57  	d := randomSlice(n+1+extra, rnd)
    58  	dCopy := make([]float64, len(d))
    59  	copy(dCopy, d)
    60  
    61  	du := randomSlice(n+extra, rnd)
    62  	duCopy := make([]float64, len(du))
    63  	copy(duCopy, du)
    64  
    65  	b := randomGeneral(m, n, ldb, rnd)
    66  	bCopy := cloneGeneral(b)
    67  
    68  	got := randomGeneral(m, n, ldc, rnd)
    69  	want := cloneGeneral(got)
    70  
    71  	// Deal with zero-sized matrices early.
    72  	if m == 0 || n == 0 {
    73  		impl.Dlagtm(trans, m, n, alpha, dl, d, du, b.Data, b.Stride, beta, got.Data, got.Stride)
    74  		if !floats.Same(dl, dlCopy) {
    75  			t.Errorf("%v: unexpected modification in dl", name)
    76  		}
    77  		if !floats.Same(d, dCopy) {
    78  			t.Errorf("%v: unexpected modification in d", name)
    79  		}
    80  		if !floats.Same(du, duCopy) {
    81  			t.Errorf("%v: unexpected modification in du", name)
    82  		}
    83  		if !floats.Same(b.Data, bCopy.Data) {
    84  			t.Errorf("%v: unexpected modification in B", name)
    85  		}
    86  		if !floats.Same(got.Data, want.Data) {
    87  			t.Errorf("%v: unexpected modification in C", name)
    88  		}
    89  		return
    90  	}
    91  
    92  	impl.Dlagtm(trans, m, n, alpha, dl, d, du, b.Data, b.Stride, beta, got.Data, got.Stride)
    93  
    94  	if !floats.Same(dl, dlCopy) {
    95  		t.Errorf("%v: unexpected modification in dl", name)
    96  	}
    97  	if !floats.Same(d, dCopy) {
    98  		t.Errorf("%v: unexpected modification in d", name)
    99  	}
   100  	if !floats.Same(du, duCopy) {
   101  		t.Errorf("%v: unexpected modification in du", name)
   102  	}
   103  	if !floats.Same(b.Data, bCopy.Data) {
   104  		t.Errorf("%v: unexpected modification in B", name)
   105  	}
   106  
   107  	// Generate a dense representation of the matrix and compute the wanted result.
   108  	a := zeros(m, m, m)
   109  	for i := 0; i < m-1; i++ {
   110  		a.Data[i*a.Stride+i] = d[i]
   111  		a.Data[i*a.Stride+i+1] = du[i]
   112  		a.Data[(i+1)*a.Stride+i] = dl[i]
   113  	}
   114  	a.Data[(m-1)*a.Stride+m-1] = d[m-1]
   115  
   116  	blas64.Gemm(trans, blas.NoTrans, alpha, a, b, beta, want)
   117  
   118  	for i := 0; i < m; i++ {
   119  		for j := 0; j < n; j++ {
   120  			got.Data[i*got.Stride+j] -= want.Data[i*want.Stride+j]
   121  		}
   122  	}
   123  	diff := dlange(lapack.MaxColumnSum, got.Rows, got.Cols, got.Data, got.Stride)
   124  	if diff > tol {
   125  		t.Errorf("%v: unexpected result; diff=%v, want<=%v", name, diff, tol)
   126  	}
   127  }