Add Dorgql, dependency, and helper function for test

testlapack/dorgql.go

@@ -0,0 +1,60 @@
+// Copyright ©2016 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/rand"
+	"testing"
+
+	"github.com/gonum/floats"
+)
+
+type Dorgqler interface {
+	Dorgql(m, n, k int, a []float64, lda int, tau, work []float64, lwork int)
+	Dorg2ler
+}
+
+func DorgqlTest(t *testing.T, impl Dorgqler) {
+	for _, test := range []struct {
+		m, n, k, lda int
+	}{
+		{5, 4, 3, 0},
+		{100, 100, 100, 0},
+		{200, 100, 50, 0},
+		{200, 200, 50, 0},
+	} {
+		m := test.m
+		n := test.n
+		k := test.k
+		lda := test.lda
+		if lda == 0 {
+			lda = n
+		}
+		a := make([]float64, m*lda)
+		for i := range a {
+			a[i] = rand.NormFloat64()
+		}
+		tau := nanSlice(min(m, n))
+		work := nanSlice(max(m, n))
+
+		impl.Dgeql2(m, n, a, lda, tau, work)
+
+		aCopy := make([]float64, len(a))
+		copy(aCopy, a)
+
+		impl.Dorg2l(m, n, k, a, lda, tau, work)
+		ans := make([]float64, len(a))
+		copy(ans, a)
+
+		impl.Dorgql(m, n, k, a, lda, tau, work, -1)
+		work = make([]float64, int(work[0]))
+		copy(a, aCopy)
+		impl.Dorgql(m, n, k, a, lda, tau, work, len(work))
+
+		if !floats.EqualApprox(a, ans, 1e-8) {
+			t.Errorf("Answer mismatch. m = %v, n = %v, k = %v", m, n, k)
+		}
+	}
+}