srotmg()

subroutine srotmg	(	real	sd1,
		real	sd2,
		real	sx1,
		real	sy1,
		real, dimension(5)	sparam )

SROTMG

Purpose:

!>
!>    CONSTRUCT THE MODIFIED GIVENS TRANSFORMATION MATRIX H WHICH ZEROS
!>    THE SECOND COMPONENT OF THE 2-VECTOR  (SQRT(SD1)*SX1,SQRT(SD2)*>    SY2)**T.
!>    WITH SPARAM(1)=SFLAG, H HAS ONE OF THE FOLLOWING FORMS..
!>
!>    SFLAG=-1.E0     SFLAG=0.E0        SFLAG=1.E0     SFLAG=-2.E0
!>
!>      (SH11  SH12)    (1.E0  SH12)    (SH11  1.E0)    (1.E0  0.E0)
!>    H=(          )    (          )    (          )    (          )
!>      (SH21  SH22),   (SH21  1.E0),   (-1.E0 SH22),   (0.E0  1.E0).
!>    LOCATIONS 2-4 OF SPARAM CONTAIN SH11,SH21,SH12, AND SH22
!>    RESPECTIVELY. (VALUES OF 1.E0, -1.E0, OR 0.E0 IMPLIED BY THE
!>    VALUE OF SPARAM(1) ARE NOT STORED IN SPARAM.)
!>
!>    THE VALUES OF GAMSQ AND RGAMSQ SET IN THE DATA STATEMENT MAY BE
!>    INEXACT.  THIS IS OK AS THEY ARE ONLY USED FOR TESTING THE SIZE
!>    OF SD1 AND SD2.  ALL ACTUAL SCALING OF DATA IS DONE USING GAM.
!>
!> 

Parameters

[in,out]	SD1	!> SD1 is REAL !>
[in,out]	SD2	!> SD2 is REAL !>
[in,out]	SX1	!> SX1 is REAL !>
[in]	SY1	!> SY1 is REAL !>
[out]	SPARAM	!> SPARAM is REAL array, dimension (5) !> SPARAM(1)=SFLAG !> SPARAM(2)=SH11 !> SPARAM(3)=SH21 !> SPARAM(4)=SH12 !> SPARAM(5)=SH22 !>

Author

Univ. of Tennessee

Univ. of California Berkeley

Univ. of Colorado Denver

NAG Ltd.