dla_wwaddw()

subroutine dla_wwaddw	(	integer	n,
		double precision, dimension( * )	x,
		double precision, dimension( * )	y,
		double precision, dimension( * )	w )

DLA_WWADDW adds a vector into a doubled-single vector.

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Purpose:

!>
!>    DLA_WWADDW adds a vector W into a doubled-single vector (X, Y).
!>
!>    This works for all extant IBM's hex and binary floating point
!>    arithmetic, but not for decimal.
!> 

Parameters

[in]	N	!> N is INTEGER !> The length of vectors X, Y, and W. !>
[in,out]	X	!> X is DOUBLE PRECISION array, dimension (N) !> The first part of the doubled-single accumulation vector. !>
[in,out]	Y	!> Y is DOUBLE PRECISION array, dimension (N) !> The second part of the doubled-single accumulation vector. !>
[in]	W	!> W is DOUBLE PRECISION array, dimension (N) !> The vector to be added. !>

Author

Univ. of Tennessee

Univ. of California Berkeley

Univ. of Colorado Denver

NAG Ltd.

Definition at line 78 of file dla_wwaddw.f.

*
*  -- LAPACK computational routine --
*  -- LAPACK is a software package provided by Univ. of Tennessee,    --
*  -- Univ. of California Berkeley, Univ. of Colorado Denver and NAG Ltd..--
*
*     .. Scalar Arguments ..
      INTEGER            N
*     ..
*     .. Array Arguments ..
      DOUBLE PRECISION   X( * ), Y( * ), W( * )
*     ..
*
*  =====================================================================
*
*     .. Local Scalars ..
      DOUBLE PRECISION   S
      INTEGER            I
*     ..
*     .. Executable Statements ..
*
      DO 10 i = 1, n
        s = x(i) + w(i)
        s = (s + s) - s
        y(i) = ((x(i) - s) + w(i)) + y(i)
        x(i) = s
 10   CONTINUE
      RETURN
*
*     End of DLA_WWADDW
*

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