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Patches pour OS/2

    1:       SUBROUTINE DLA_WWADDW( N, X, Y, W )
    2: *
    3: *     -- LAPACK routine (version 3.2.2)                                 --
    4: *     -- Contributed by James Demmel, Deaglan Halligan, Yozo Hida and --
    5: *     -- Jason Riedy of Univ. of California Berkeley.                 --
    6: *     -- June 2010                                                    --
    7: *
    8: *     -- LAPACK is a software package provided by Univ. of Tennessee, --
    9: *     -- Univ. of California Berkeley and NAG Ltd.                    --
   10: *
   11:       IMPLICIT NONE
   12: *     ..
   13: *     .. Scalar Arguments ..
   14:       INTEGER            N
   15: *     ..
   16: *     .. Array Arguments ..
   17:       DOUBLE PRECISION   X( * ), Y( * ), W( * )
   18: *     ..
   19: *
   20: *     Purpose
   21: *     =======
   22: *
   23: *     DLA_WWADDW adds a vector W into a doubled-single vector (X, Y).
   24: *
   25: *     This works for all extant IBM's hex and binary floating point
   26: *     arithmetics, but not for decimal.
   27: *
   28: *     Arguments
   29: *     =========
   30: *
   31: *     N      (input) INTEGER
   32: *            The length of vectors X, Y, and W.
   33: *
   34: *     X      (input/output) DOUBLE PRECISION array, dimension (N)
   35: *            The first part of the doubled-single accumulation vector.
   36: *
   37: *     Y      (input/output) DOUBLE PRECISION array, dimension (N)
   38: *            The second part of the doubled-single accumulation vector.
   39: *
   40: *     W      (input) DOUBLE PRECISION array, dimension (N)
   41: *            The vector to be added.
   42: *
   43: *  =====================================================================
   44: *
   45: *     .. Local Scalars ..
   46:       DOUBLE PRECISION   S
   47:       INTEGER            I
   48: *     ..
   49: *     .. Executable Statements ..
   50: *
   51:       DO 10 I = 1, N
   52:         S = X(I) + W(I)
   53:         S = (S + S) - S
   54:         Y(I) = ((X(I) - S) + W(I)) + Y(I)
   55:         X(I) = S
   56:  10   CONTINUE
   57:       RETURN
   58:       END