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native: reduce indentation in Dlatrs

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This commit is contained in:
Vladimir Chalupecky
2017-03-19 19:31:01 +01:00
parent ff0bc87843
commit c27cb7f8f3
1 changed files with 147 additions and 140 deletions
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29
native/dlatrs.go
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@@ -55,7 +55,8 @@ func (impl Implementation) Dlatrs(uplo blas.Uplo, trans blas.Transpose, diag bla
bi := blas64.Implementation()
if !normin {
if upper {
for j := 0; j < n; j++ {
cnorm[0] = 0
for j := 1; j < n; j++ {
cnorm[j] = bi.Dasum(j, a[j:], lda)
}
} else {
@@ -95,14 +96,14 @@ func (impl Implementation) Dlatrs(uplo blas.Uplo, trans blas.Transpose, diag bla
// Compute the growth in A * x = b.
if tscal != 1 {
grow = 0
goto Finish
goto Solve
}
if nonUnit {
grow = 1 / math.Max(xbnd, smlnum)
xbnd = grow
for j := jfirst; j != jlast; j += jinc {
if grow <= smlnum {
goto Finish
goto Solve
}
tjj := math.Abs(a[j*lda+j])
xbnd = math.Min(xbnd, math.Min(1, tjj)*grow)
@@ -117,7 +118,7 @@ func (impl Implementation) Dlatrs(uplo blas.Uplo, trans blas.Transpose, diag bla
grow = math.Min(1, 1/math.Max(xbnd, smlnum))
for j := jfirst; j != jlast; j += jinc {
if grow <= smlnum {
goto Finish
goto Solve
}
grow *= 1 / (1 + cnorm[j])
}
@@ -134,14 +135,14 @@ func (impl Implementation) Dlatrs(uplo blas.Uplo, trans blas.Transpose, diag bla
}
if tscal != 1 {
grow = 0
goto Finish
goto Solve
}
if nonUnit {
grow = 1 / (math.Max(xbnd, smlnum))
xbnd = grow
for j := jfirst; j != jlast; j += jinc {
if grow <= smlnum {
goto Finish
goto Solve
}
xj := 1 + cnorm[j]
grow = math.Min(grow, xbnd/xj)
@@ -155,7 +156,7 @@ func (impl Implementation) Dlatrs(uplo blas.Uplo, trans blas.Transpose, diag bla
grow = math.Min(1, 1/math.Max(xbnd, smlnum))
for j := jfirst; j != jlast; j += jinc {
if grow <= smlnum {
goto Finish
goto Solve
}
xj := 1 + cnorm[j]
grow /= xj
@@ -163,11 +164,18 @@ func (impl Implementation) Dlatrs(uplo blas.Uplo, trans blas.Transpose, diag bla
}
}
Finish:
Solve:
if grow*tscal > smlnum {
// Use the Level 2 BLAS solve if the reciprocal of the bound on
// elements of X is not too small.
bi.Dtrsv(uplo, trans, diag, n, a, lda, x, 1)
// TODO(btracey): check if this else is everything
} else {
if tscal != 1 {
bi.Dscal(n, 1/tscal, cnorm, 1)
}
return scale
}
// Use a Level 1 BLAS solve, scaling intermediate results.
if xmax > bignum {
scale = bignum / xmax
bi.Dscal(n, scale, x, 1)
@@ -333,7 +341,6 @@ Finish:
}
}
scale /= tscal
}
if tscal != 1 {
bi.Dscal(n, 1/tscal, cnorm, 1)
}