testlapack: review comments for Dlatm1

testlapack/matgen.go

@@ -9,30 +9,30 @@ import (
 	"math/rand"
 )
 
-// Dlatm1 computes the entries of d as specified by mode, cond and rsign.
+// Dlatm1 computes the entries of dst as specified by mode, cond and rsign.
 //
-// mode describes how d will be computed:
-//  |mode| == 1: d[0] = 1 and d[1:n] = 1/cond
-//  |mode| == 2: d[:n-1] = 1/cond and d[n-1] = 1
-//  |mode| == 3: d[i] = cond^{-i/(n-1)}, i=0,...,n-1
-//  |mode| == 4: d[i] = 1 - i*(1-1/cond)/(n-1)
-//  |mode| == 5: d[i] = random number in the range (1/cond, 1) such that
+// mode describes how dst will be computed:
+//  |mode| == 1: dst[0] = 1 and dst[1:n] = 1/cond
+//  |mode| == 2: dst[:n-1] = 1/cond and dst[n-1] = 1
+//  |mode| == 3: dst[i] = cond^{-i/(n-1)}, i=0,...,n-1
+//  |mode| == 4: dst[i] = 1 - i*(1-1/cond)/(n-1)
+//  |mode| == 5: dst[i] = random number in the range (1/cond, 1) such that
 //                    their logarithms are uniformly distributed
-//  |mode| == 6: d[i] = random number from the distribution given by dist
-// If mode is negative, the order of the elements of d will be reversed.
+//  |mode| == 6: dst[i] = random number from the distribution given by dist
+// If mode is negative, the order of the elements of dst will be reversed.
 // For other values of mode Dlatm1 will panic.
 //
-// if rsign is true and mode is not ±6, each entry of d will be multiplied by 1
+// If rsign is true and mode is not ±6, each entry of dst will be multiplied by 1
 // or -1 with probability 0.5
 //
 // dist specifies the type of distribution to be used when mode == ±6:
-//  dist == 1: Uniform(0,1)
-//  dist == 2: Uniform(-1,1)
+//  dist == 1: Uniform[0,1)
+//  dist == 2: Uniform[-1,1)
 //  dist == 3: Normal(0,1)
 // For other values of dist Dlatm1 will panic.
 //
 // rnd is used as a source of random numbers.
-func Dlatm1(mode int, cond float64, rsign bool, dist int, rnd *rand.Rand, d []float64) {
+func Dlatm1(dst []float64, mode int, cond float64, rsign bool, dist int, rnd *rand.Rand) {
 	amode := mode
 	if amode < 0 {
 		amode = -amode
@@ -43,76 +43,76 @@ func Dlatm1(mode int, cond float64, rsign bool, dist int, rnd *rand.Rand, d []fl
 	if cond < 1 {
 		panic("testlapack: cond < 1")
 	}
-	if dist != 1 && dist != 2 && dist != 3 {
+	if amode == 6 && (dist < 1 || 3 < dist) {
 		panic("testlapack: invalid dist")
 	}
 
-	n := len(d)
+	n := len(dst)
 	if n == 0 {
 		return
 	}
 
 	switch amode {
 	case 1:
-		d[0] = 1
+		dst[0] = 1
 		for i := 1; i < n; i++ {
-			d[i] = 1 / cond
+			dst[i] = 1 / cond
 		}
 	case 2:
 		for i := 0; i < n-1; i++ {
-			d[i] = 1
+			dst[i] = 1
 		}
-		d[n-1] = 1 / cond
+		dst[n-1] = 1 / cond
 	case 3:
-		d[0] = 1
+		dst[0] = 1
 		if n > 1 {
 			alpha := math.Pow(cond, -1/float64(n-1))
 			for i := 1; i < n; i++ {
-				d[i] = math.Pow(alpha, float64(i))
+				dst[i] = math.Pow(alpha, float64(i))
 			}
 		}
 	case 4:
-		d[0] = 1
+		dst[0] = 1
 		if n > 1 {
 			condInv := 1 / cond
 			alpha := (1 - condInv) / float64(n-1)
 			for i := 1; i < n; i++ {
-				d[i] = float64(n-i-1)*alpha + condInv
+				dst[i] = float64(n-i-1)*alpha + condInv
 			}
 		}
 	case 5:
 		alpha := math.Log(1 / cond)
-		for i := range d {
-			d[i] = math.Exp(alpha * rnd.Float64())
+		for i := range dst {
+			dst[i] = math.Exp(alpha * rnd.Float64())
 		}
 	case 6:
 		switch dist {
 		case 1:
-			for i := range d {
-				d[i] = rnd.Float64()
+			for i := range dst {
+				dst[i] = rnd.Float64()
 			}
 		case 2:
-			for i := range d {
-				d[i] = 2*rnd.Float64() - 1
+			for i := range dst {
+				dst[i] = 2*rnd.Float64() - 1
 			}
 		case 3:
-			for i := range d {
-				d[i] = rnd.NormFloat64()
+			for i := range dst {
+				dst[i] = rnd.NormFloat64()
 			}
 		}
 	}
 
-	if rsign && mode != -6 && mode != 6 {
-		for i, v := range d {
+	if rsign && amode != 6 {
+		for i, v := range dst {
 			if rnd.Float64() < 0.5 {
-				d[i] = -v
+				dst[i] = -v
 			}
 		}
 	}
 
 	if mode < 0 {
 		for i := 0; i < n/2; i++ {
-			d[i], d[n-i-1] = d[n-i-1], d[i]
+			dst[i], dst[n-i-1] = dst[n-i-1], dst[i]
 		}
 	}
 }