public interface lartgp
LARTGP generates a plane rotation so that
[ CS SN ] . [ F ] = [ R ] where CS2 + SN2 = 1.
[ -SN CS ] [ G ] [ 0 ]
This is a slower, more accurate version of the Level 1 BLAS routine DROTG,
with the following other differences:
F and G are unchanged on return.
If G=0, then CS=(+/-)1 and SN=0.
If F=0 and (G .ne. 0), then CS=0 and SN=(+/-)1.
The sign is chosen so that R >= 0.
Subroutines
Arguments
| Type |
Intent | Optional | Attributes |
|
Name |
|
|
real(kind=dp),
|
intent(in) |
|
|
:: |
f |
|
|
real(kind=dp),
|
intent(in) |
|
|
:: |
g |
|
|
real(kind=dp),
|
intent(out) |
|
|
:: |
cs |
|
|
real(kind=dp),
|
intent(out) |
|
|
:: |
sn |
|
|
real(kind=dp),
|
intent(out) |
|
|
:: |
r |
|
Arguments
| Type |
Intent | Optional | Attributes |
|
Name |
|
|
real(kind=sp),
|
intent(in) |
|
|
:: |
f |
|
|
real(kind=sp),
|
intent(in) |
|
|
:: |
g |
|
|
real(kind=sp),
|
intent(out) |
|
|
:: |
cs |
|
|
real(kind=sp),
|
intent(out) |
|
|
:: |
sn |
|
|
real(kind=sp),
|
intent(out) |
|
|
:: |
r |
|
Module Procedures