github.com/gonum/lapack@v0.0.0-20181123203213-e4cdc5a0bff9/testlapack/dorg2r.go (about)

     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  	"fmt"
     9  	"math/rand"
    10  	"testing"
    11  
    12  	"github.com/gonum/floats"
    13  )
    14  
    15  type Dorg2rer interface {
    16  	Dgeqrfer
    17  	Dorg2r(m, n, k int, a []float64, lda int, tau []float64, work []float64)
    18  }
    19  
    20  func Dorg2rTest(t *testing.T, impl Dorg2rer) {
    21  	rnd := rand.New(rand.NewSource(1))
    22  	for _, test := range []struct {
    23  		m, n, k, lda int
    24  	}{
    25  		{3, 3, 0, 0},
    26  		{4, 3, 0, 0},
    27  		{3, 3, 2, 0},
    28  		{4, 3, 2, 0},
    29  
    30  		{5, 5, 0, 20},
    31  		{5, 5, 3, 20},
    32  		{10, 5, 0, 20},
    33  		{10, 5, 2, 20},
    34  	} {
    35  		m := test.m
    36  		n := test.n
    37  		lda := test.lda
    38  		if lda == 0 {
    39  			lda = test.n
    40  		}
    41  		a := make([]float64, m*lda)
    42  		for i := range a {
    43  			a[i] = rnd.NormFloat64()
    44  		}
    45  		k := min(m, n)
    46  		tau := make([]float64, k)
    47  		work := make([]float64, 1)
    48  		impl.Dgeqrf(m, n, a, lda, tau, work, -1)
    49  		work = make([]float64, int(work[0]))
    50  		impl.Dgeqrf(m, n, a, lda, tau, work, len(work))
    51  
    52  		k = test.k
    53  		if k == 0 {
    54  			k = n
    55  		}
    56  		q := constructQK("QR", m, n, k, a, lda, tau)
    57  
    58  		impl.Dorg2r(m, n, k, a, lda, tau, work)
    59  
    60  		// Check that the first n columns match.
    61  		same := true
    62  		for i := 0; i < m; i++ {
    63  			for j := 0; j < n; j++ {
    64  				if !floats.EqualWithinAbsOrRel(q.Data[i*q.Stride+j], a[i*lda+j], 1e-12, 1e-12) {
    65  					same = false
    66  					break
    67  				}
    68  			}
    69  		}
    70  		if !same {
    71  			fmt.Println()
    72  			fmt.Println("a =")
    73  			printRowise(a, m, n, lda, false)
    74  			fmt.Println("q =")
    75  			printRowise(q.Data, q.Rows, q.Cols, q.Stride, false)
    76  			t.Errorf("Q mismatch")
    77  		}
    78  	}
    79  }