public interface laqtr
LAQTR solves the real quasi-triangular system
op(T)p = scalec, if LREAL = .TRUE.
or the complex quasi-triangular systems
op(T + iB)(p+iq) = scale(c+id), if LREAL = .FALSE.
in real arithmetic, where T is upper quasi-triangular.
If LREAL = .FALSE., then the first diagonal block of T must be
1 by 1, B is the specially structured matrix
B = [ b(1) b(2) ... b(n) ]
[ w ]
[ w ]
[ . ]
[ w ]
op(A) = A or AT, AT denotes the transpose of
matrix A.
On input, X = [ c ]. On output, X = [ p ].
[ d ] [ q ]
This subroutine is designed for the condition number estimation
in routine DTRSNA.
Subroutines
Arguments
| Type |
Intent | Optional | Attributes |
|
Name |
|
|
logical(kind=lk),
|
intent(in) |
|
|
:: |
ltran |
|
|
logical(kind=lk),
|
intent(in) |
|
|
:: |
lreal |
|
|
integer(kind=ilp),
|
intent(in) |
|
|
:: |
n |
|
|
real(kind=dp),
|
intent(in) |
|
|
:: |
t(ldt,*) |
|
|
integer(kind=ilp),
|
intent(in) |
|
|
:: |
ldt |
|
|
real(kind=dp),
|
intent(in) |
|
|
:: |
b(*) |
|
|
real(kind=dp),
|
intent(in) |
|
|
:: |
w |
|
|
real(kind=dp),
|
intent(out) |
|
|
:: |
scale |
|
|
real(kind=dp),
|
intent(inout) |
|
|
:: |
x(*) |
|
|
real(kind=dp),
|
intent(out) |
|
|
:: |
work(*) |
|
|
integer(kind=ilp),
|
intent(out) |
|
|
:: |
info |
|
Arguments
| Type |
Intent | Optional | Attributes |
|
Name |
|
|
logical(kind=lk),
|
intent(in) |
|
|
:: |
ltran |
|
|
logical(kind=lk),
|
intent(in) |
|
|
:: |
lreal |
|
|
integer(kind=ilp),
|
intent(in) |
|
|
:: |
n |
|
|
real(kind=sp),
|
intent(in) |
|
|
:: |
t(ldt,*) |
|
|
integer(kind=ilp),
|
intent(in) |
|
|
:: |
ldt |
|
|
real(kind=sp),
|
intent(in) |
|
|
:: |
b(*) |
|
|
real(kind=sp),
|
intent(in) |
|
|
:: |
w |
|
|
real(kind=sp),
|
intent(out) |
|
|
:: |
scale |
|
|
real(kind=sp),
|
intent(inout) |
|
|
:: |
x(*) |
|
|
real(kind=sp),
|
intent(out) |
|
|
:: |
work(*) |
|
|
integer(kind=ilp),
|
intent(out) |
|
|
:: |
info |
|
Module Procedures