srotm.f3
Usage
Functions/Subroutines
subroutine srotm (n, sx, incx, sy, incy, sparam)
SROTM
Function/Subroutine Documentation
subroutine srotm (integer n, real, dimension(*) sx, integer incx, real, dimension(*) sy, integer incy, real, dimension(5) sparam)
SROTM
Purpose:
!>
!> APPLY THE MODIFIED GIVENS TRANSFORMATION, H, TO THE 2 BY N MATRIX
!>
!> (SX**T) , WHERE **T INDICATES TRANSPOSE. THE ELEMENTS OF SX ARE IN
!> (SX**T)
!>
!> SX(LX+I*INCX), I = 0 TO N-1, WHERE LX = 1 IF INCX .GE. 0, ELSE
!> LX = (-INCX)*N, AND SIMILARLY FOR SY USING USING LY AND INCY.
!> 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).
!> SEE SROTMG FOR A DESCRIPTION OF DATA STORAGE IN SPARAM.
!>
!>
Parameters
N
!> N is INTEGER !> number of elements in input vector(s) !>
SX
!> SX is REAL array, dimension ( 1 + ( N - 1 )*abs( INCX ) ) !>
INCX
!> INCX is INTEGER !> storage spacing between elements of SX !>
SY
!> SY is REAL array, dimension ( 1 + ( N - 1 )*abs( INCY ) ) !>
INCY
!> INCY is INTEGER !> storage spacing between elements of SY !>
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.
Definition at line 96 of file srotm.f.
Releases
2 releases since Debian 9 (Stretch); the text changed 1 time.