SROTM(1)

NAME
LAPACK-3 - APPLY THE MODIFIED GIVENS TRANSFORMATION, H, TO THE 2 BY N MATRIX (SX**T) , WHERE **T INDICATES TRANSPOSE

SYNOPSIS

SUBROUTINE SROTM(N,SX,INCX,SY,INCY,SPARAM)

INTEGER
    INCX,INCY,N

REAL
    SPARAM(5),SX(*),SY(*)

PURPOSE
   APPLY THE MODIFIED GIVENS TRANSFORMATION, H, TO THE 2 BY N MATRIX
    (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.

ARGUMENTS

N      (input) INTEGER
     number of elements in input vector(s)

SX     (input/output) REAL array, dimension N
     double precision vector with N elements

INCX   (input) INTEGER
     storage spacing between elements of SX

SY     (input/output) REAL array, dimension N
     double precision vector with N elements

INCY   (input) INTEGER
     storage spacing between elements of SY
     SPARAM (input/output) REAL array, dimension 5
     SPARAM(1)=SFLAG
     SPARAM(2)=SH11
     SPARAM(3)=SH21
     SPARAM(4)=SH12
     SPARAM(5)=SH22