native,cgo: add error checking to Dlaswp and update docs
MODIFY
cgo/lapack.go
cgo/lapack.go
@@ -28,8 +28,10 @@ const (
badHowMany = "lapack: bad HowMany"
badIlo = "lapack: ilo out of range"
badIhi = "lapack: ihi out of range"
- badIpiv = "lapack: insufficient permutation length"
+ badIpiv = "lapack: bad permutation length"
badJob = "lapack: bad Job"
+ badK1 = "lapack: k1 out of range"
+ badK2 = "lapack: k2 out of range"
badKperm = "lapack: incorrect permutation length"
badLdA = "lapack: index of a out of range"
badNorm = "lapack: bad norm"
@@ -511,12 +513,31 @@ func (impl Implementation) Dlasrt(s lapack.Sort, n int, d []float64) {
lapacke.Dlasrt(byte(s), n, d[:n])
}
-// Dlaswp swaps the rows k1 to k2 of a according to the indices in ipiv.
-// a is a matrix with n columns and stride lda. incX is the increment for ipiv.
-// k1 and k2 are zero-indexed. If incX is negative, then loops from k2 to k1
+// Dlaswp swaps the rows k1 to k2 of a rectangular matrix A according to the
+// indices in ipiv so that row k is swapped with ipiv[k].
+//
+// n is the number of columns of A and incX is the increment for ipiv. If incX
+// is 1, the swaps are applied from k1 to k2. If incX is -1, the swaps are
+// applied in reverse order from k2 to k1. For other values of incX Dlaswp will
+// panic. ipiv must have length k2+1, otherwise Dlaswp will panic.
+//
+// The indices k1, k2, and the elements of ipiv are zero-based.
//
// Dlaswp is an internal routine. It is exported for testing purposes.
func (impl Implementation) Dlaswp(n int, a []float64, lda, k1, k2 int, ipiv []int, incX int) {
+ switch {
+ case n < 0:
+ panic(nLT0)
+ case k2 < 0:
+ panic(badK2)
+ case k1 < 0 || k2 < k1:
+ panic(badK1)
+ case len(ipiv) != k2+1:
+ panic(badIpiv)
+ case incX != 1 && incX != -1:
+ panic(absIncNotOne)
+ }
+
ipiv32 := make([]int32, len(ipiv))
for i, v := range ipiv {
ipiv32[i] = int32(v + 1)

MODIFY
native/dlaswp.go
native/dlaswp.go
@@ -6,15 +6,34 @@ package native
import "github.com/gonum/blas/blas64"
-// Dlaswp swaps the rows k1 to k2 of a according to the indices in ipiv.
-// a is a matrix with n columns and stride lda. incX is the increment for ipiv.
-// k1 and k2 are zero-indexed. If incX is negative, then loops from k2 to k1
+// Dlaswp swaps the rows k1 to k2 of a rectangular matrix A according to the
+// indices in ipiv so that row k is swapped with ipiv[k].
+//
+// n is the number of columns of A and incX is the increment for ipiv. If incX
+// is 1, the swaps are applied from k1 to k2. If incX is -1, the swaps are
+// applied in reverse order from k2 to k1. For other values of incX Dlaswp will
+// panic. ipiv must have length k2+1, otherwise Dlaswp will panic.
+//
+// The indices k1, k2, and the elements of ipiv are zero-based.
//
// Dlaswp is an internal routine. It is exported for testing purposes.
-func (impl Implementation) Dlaswp(n int, a []float64, lda, k1, k2 int, ipiv []int, incX int) {
- if incX != 1 && incX != -1 {
+func (impl Implementation) Dlaswp(n int, a []float64, lda int, k1, k2 int, ipiv []int, incX int) {
+ switch {
+ case n < 0:
+ panic(nLT0)
+ case k2 < 0:
+ panic(badK2)
+ case k1 < 0 || k2 < k1:
+ panic(badK1)
+ case len(ipiv) != k2+1:
+ panic(badIpiv)
+ case incX != 1 && incX != -1:
panic(absIncNotOne)
}
+
+ if n == 0 {
+ return
+ }
bi := blas64.Implementation()
if incX == 1 {
for k := k1; k <= k2; k++ {

MODIFY
native/general.go
native/general.go
@@ -32,8 +32,10 @@ const (
badHowMany = "lapack: bad HowMany"
badIlo = "lapack: ilo out of range"
badIhi = "lapack: ihi out of range"
- badIpiv = "lapack: insufficient permutation length"
+ badIpiv = "lapack: bad permutation length"
badJob = "lapack: bad Job"
+ badK1 = "lapack: k1 out of range"
+ badK2 = "lapack: k2 out of range"
badKperm = "lapack: incorrect permutation length"
badLdA = "lapack: index of a out of range"
badNorm = "lapack: bad norm"

native,cgo: add error checking to Dlaswp and update docs