mirror of
https://github.com/gonum/gonum.git
synced 2025-10-05 23:26:52 +08:00
116 lines
3.3 KiB
Go
116 lines
3.3 KiB
Go
// Copyright ©2018 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 testblas
|
|
|
|
import (
|
|
"fmt"
|
|
"testing"
|
|
|
|
"golang.org/x/exp/rand"
|
|
"gonum.org/v1/gonum/blas"
|
|
)
|
|
|
|
type Ztbsver interface {
|
|
Ztbsv(uplo blas.Uplo, trans blas.Transpose, diag blas.Diag, n, k int, ab []complex128, ldab int, x []complex128, incX int)
|
|
|
|
Ztbmver
|
|
}
|
|
|
|
func ZtbsvTest(t *testing.T, impl Ztbsver) {
|
|
rnd := rand.New(rand.NewSource(1))
|
|
for _, uplo := range []blas.Uplo{blas.Upper, blas.Lower} {
|
|
for _, trans := range []blas.Transpose{blas.NoTrans, blas.Trans, blas.ConjTrans} {
|
|
for _, diag := range []blas.Diag{blas.NonUnit, blas.Unit} {
|
|
for _, n := range []int{1, 2, 3, 4, 10} {
|
|
for k := 0; k < n; k++ {
|
|
for _, ldab := range []int{k + 1, k + 1 + 10} {
|
|
for _, incX := range []int{-4, 1, 5} {
|
|
ztbsvTest(t, impl, rnd, uplo, trans, diag, n, k, ldab, incX)
|
|
}
|
|
}
|
|
}
|
|
}
|
|
}
|
|
}
|
|
}
|
|
}
|
|
|
|
// ztbsvTest tests Ztbsv by checking whether Ztbmv followed by Ztbsv
|
|
// round-trip.
|
|
func ztbsvTest(t *testing.T, impl Ztbsver, rnd *rand.Rand, uplo blas.Uplo, trans blas.Transpose, diag blas.Diag, n, k, ldab, incX int) {
|
|
const tol = 1e-10
|
|
|
|
// Allocate a dense-storage triangular band matrix filled with NaNs that
|
|
// will be used as a for creating the actual triangular band matrix.
|
|
lda := max(1, n)
|
|
a := makeZGeneral(nil, n, n, lda)
|
|
// Fill the referenced triangle of A with random data within the band
|
|
// and with zeros outside.
|
|
if uplo == blas.Upper {
|
|
for i := 0; i < n; i++ {
|
|
for j := i; j < min(n, i+k+1); j++ {
|
|
re := rnd.NormFloat64()
|
|
im := rnd.NormFloat64()
|
|
a[i*lda+j] = complex(re, im)
|
|
}
|
|
for j := i + k + 1; j < n; j++ {
|
|
a[i*lda+j] = 0
|
|
}
|
|
}
|
|
} else {
|
|
for i := 0; i < n; i++ {
|
|
for j := 0; j < i-k; j++ {
|
|
a[i*lda+j] = 0
|
|
}
|
|
for j := max(0, i-k); j <= i; j++ {
|
|
re := rnd.NormFloat64()
|
|
im := rnd.NormFloat64()
|
|
a[i*lda+j] = complex(re, im)
|
|
}
|
|
}
|
|
}
|
|
if diag == blas.Unit {
|
|
// The diagonal should not be referenced by Ztbmv and Ztbsv, so
|
|
// invalidate it with NaNs.
|
|
for i := 0; i < n; i++ {
|
|
a[i*lda+i] = znan
|
|
}
|
|
}
|
|
// Create the triangular band matrix.
|
|
ab := zPackTriBand(k, ldab, uplo, n, a, lda)
|
|
abCopy := make([]complex128, len(ab))
|
|
copy(abCopy, ab)
|
|
|
|
// Generate a random complex vector x.
|
|
xtest := make([]complex128, n)
|
|
for i := range xtest {
|
|
re := rnd.NormFloat64()
|
|
im := rnd.NormFloat64()
|
|
xtest[i] = complex(re, im)
|
|
}
|
|
x := makeZVector(xtest, incX)
|
|
|
|
// Store a copy of x as the correct result that we want.
|
|
want := make([]complex128, len(x))
|
|
copy(want, x)
|
|
|
|
// Compute A*x, denoting the result by b and storing it in x.
|
|
impl.Ztbmv(uplo, trans, diag, n, k, ab, ldab, x, incX)
|
|
// Solve A*x = b, that is, x = A^{-1}*b = A^{-1}*A*x.
|
|
impl.Ztbsv(uplo, trans, diag, n, k, ab, ldab, x, incX)
|
|
// If Ztbsv is correct, A^{-1}*A = I and x contains again its original value.
|
|
|
|
name := fmt.Sprintf("uplo=%v,trans=%v,diag=%v,n=%v,k=%v,ldab=%v,incX=%v", uplo, trans, diag, n, k, ldab, incX)
|
|
if !zsame(ab, abCopy) {
|
|
t.Errorf("%v: unexpected modification of A", name)
|
|
}
|
|
if !zSameAtNonstrided(x, want, incX) {
|
|
t.Errorf("%v: unexpected modification of x\nwant %v\ngot %v", name, want, x)
|
|
}
|
|
if !zEqualApproxAtStrided(x, want, incX, tol) {
|
|
t.Errorf("%v: unexpected result\nwant %v\ngot %v", name, want, x)
|
|
}
|
|
}
|