mirror of
https://github.com/gonum/gonum.git
synced 2025-10-04 23:02:42 +08:00
17ea55aedb
Apply (with manual curation after the fact):
* s/^T/U+1d40/g
* s/^H/U+1d34/g
* s/, {2,3}if / $1/g
Some additional manual editing of odd formatting.
81 lines
1.8 KiB
Go
81 lines
1.8 KiB
Go
// Copyright ©2017 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 (
|
||
"testing"
|
||
|
||
"golang.org/x/exp/rand"
|
||
|
||
"gonum.org/v1/gonum/blas/blas64"
|
||
)
|
||
|
||
func TestDlagsy(t *testing.T) {
|
||
const tol = 1e-14
|
||
rnd := rand.New(rand.NewSource(1))
|
||
for _, n := range []int{0, 1, 2, 3, 4, 5, 10, 50} {
|
||
for _, lda := range []int{0, 2*n + 1} {
|
||
if lda == 0 {
|
||
lda = max(1, n)
|
||
}
|
||
// D is the identity matrix I.
|
||
d := make([]float64, n)
|
||
for i := range d {
|
||
d[i] = 1
|
||
}
|
||
// Allocate an n×n symmetric matrix A and fill it with NaNs.
|
||
a := nanSlice(n * lda)
|
||
work := make([]float64, 2*n)
|
||
// Compute A = U * D * Uᵀ where U is a random orthogonal matrix.
|
||
Dlagsy(n, 0, d, a, lda, rnd, work)
|
||
// A should be the identity matrix because
|
||
// A = U * D * Uᵀ = U * I * Uᵀ = U * Uᵀ = I.
|
||
dist := distFromIdentity(n, a, lda)
|
||
if dist > tol {
|
||
t.Errorf("Case n=%v,lda=%v: |A-I|=%v is too large", n, lda, dist)
|
||
}
|
||
}
|
||
}
|
||
}
|
||
|
||
func TestDlagge(t *testing.T) {
|
||
rnd := rand.New(rand.NewSource(1))
|
||
for _, n := range []int{0, 1, 2, 3, 4, 5, 10, 50} {
|
||
for _, lda := range []int{0, 2*n + 1} {
|
||
if lda == 0 {
|
||
lda = max(1, n)
|
||
}
|
||
d := make([]float64, n)
|
||
for i := range d {
|
||
d[i] = 1
|
||
}
|
||
a := blas64.General{
|
||
Rows: n,
|
||
Cols: n,
|
||
Stride: lda,
|
||
Data: nanSlice(n * lda),
|
||
}
|
||
work := make([]float64, a.Rows+a.Cols)
|
||
|
||
Dlagge(a.Rows, a.Cols, 0, 0, d, a.Data, a.Stride, rnd, work)
|
||
|
||
if !isOrthogonal(a) {
|
||
t.Errorf("Case n=%v,lda=%v: unexpected result", n, lda)
|
||
}
|
||
}
|
||
}
|
||
|
||
}
|
||
|
||
func TestRandomOrthogonal(t *testing.T) {
|
||
rnd := rand.New(rand.NewSource(1))
|
||
for n := 1; n <= 20; n++ {
|
||
q := randomOrthogonal(n, rnd)
|
||
if !isOrthogonal(q) {
|
||
t.Errorf("Case n=%v: Q not orthogonal", n)
|
||
}
|
||
}
|
||
}
|