srotm()

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

[in]	N	N is INTEGER number of elements in input vector(s)
[in,out]	SX	SX is REAL array, dimension ( 1 + ( N - 1 )*abs( INCX ) )
[in]	INCX	INCX is INTEGER storage spacing between elements of SX
[in,out]	SY	SY is REAL array, dimension ( 1 + ( N - 1 )*abs( INCY ) )
[in]	INCY	INCY is INTEGER storage spacing between elements of SY
[in]	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.