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Première mise à jour de lapack et blas.

    1: *> \brief \b DAXPY
    2: *
    3: *  =========== DOCUMENTATION ===========
    4: *
    5: * Online html documentation available at
    6: *            http://www.netlib.org/lapack/explore-html/
    7: *
    8: *  Definition:
    9: *  ===========
   10: *
   11: *       SUBROUTINE DAXPY(N,DA,DX,INCX,DY,INCY)
   12: *
   13: *       .. Scalar Arguments ..
   14: *       DOUBLE PRECISION DA
   15: *       INTEGER INCX,INCY,N
   16: *       ..
   17: *       .. Array Arguments ..
   18: *       DOUBLE PRECISION DX(*),DY(*)
   19: *       ..
   20: *
   21: *
   22: *> \par Purpose:
   23: *  =============
   24: *>
   25: *> \verbatim
   26: *>
   27: *>    DAXPY constant times a vector plus a vector.
   28: *>    uses unrolled loops for increments equal to one.
   29: *> \endverbatim
   30: *
   31: *  Arguments:
   32: *  ==========
   33: *
   34: *> \param[in] N
   35: *> \verbatim
   36: *>          N is INTEGER
   37: *>         number of elements in input vector(s)
   38: *> \endverbatim
   39: *>
   40: *> \param[in] DA
   41: *> \verbatim
   42: *>          DA is DOUBLE PRECISION
   43: *>           On entry, DA specifies the scalar alpha.
   44: *> \endverbatim
   45: *>
   46: *> \param[in] DX
   47: *> \verbatim
   48: *>          DX is DOUBLE PRECISION array, dimension ( 1 + ( N - 1 )*abs( INCX ) )
   49: *> \endverbatim
   50: *>
   51: *> \param[in] INCX
   52: *> \verbatim
   53: *>          INCX is INTEGER
   54: *>         storage spacing between elements of DX
   55: *> \endverbatim
   56: *>
   57: *> \param[in,out] DY
   58: *> \verbatim
   59: *>          DY is DOUBLE PRECISION array, dimension ( 1 + ( N - 1 )*abs( INCY ) )
   60: *> \endverbatim
   61: *>
   62: *> \param[in] INCY
   63: *> \verbatim
   64: *>          INCY is INTEGER
   65: *>         storage spacing between elements of DY
   66: *> \endverbatim
   67: *
   68: *  Authors:
   69: *  ========
   70: *
   71: *> \author Univ. of Tennessee
   72: *> \author Univ. of California Berkeley
   73: *> \author Univ. of Colorado Denver
   74: *> \author NAG Ltd.
   75: *
   76: *> \ingroup double_blas_level1
   77: *
   78: *> \par Further Details:
   79: *  =====================
   80: *>
   81: *> \verbatim
   82: *>
   83: *>     jack dongarra, linpack, 3/11/78.
   84: *>     modified 12/3/93, array(1) declarations changed to array(*)
   85: *> \endverbatim
   86: *>
   87: *  =====================================================================
   88:       SUBROUTINE DAXPY(N,DA,DX,INCX,DY,INCY)
   89: *
   90: *  -- Reference BLAS level1 routine --
   91: *  -- Reference BLAS is a software package provided by Univ. of Tennessee,    --
   92: *  -- Univ. of California Berkeley, Univ. of Colorado Denver and NAG Ltd..--
   93: *
   94: *     .. Scalar Arguments ..
   95:       DOUBLE PRECISION DA
   96:       INTEGER INCX,INCY,N
   97: *     ..
   98: *     .. Array Arguments ..
   99:       DOUBLE PRECISION DX(*),DY(*)
  100: *     ..
  101: *
  102: *  =====================================================================
  103: *
  104: *     .. Local Scalars ..
  105:       INTEGER I,IX,IY,M,MP1
  106: *     ..
  107: *     .. Intrinsic Functions ..
  108:       INTRINSIC MOD
  109: *     ..
  110:       IF (N.LE.0) RETURN
  111:       IF (DA.EQ.0.0d0) RETURN
  112:       IF (INCX.EQ.1 .AND. INCY.EQ.1) THEN
  113: *
  114: *        code for both increments equal to 1
  115: *
  116: *
  117: *        clean-up loop
  118: *
  119:          M = MOD(N,4)
  120:          IF (M.NE.0) THEN
  121:             DO I = 1,M
  122:                DY(I) = DY(I) + DA*DX(I)
  123:             END DO
  124:          END IF
  125:          IF (N.LT.4) RETURN
  126:          MP1 = M + 1
  127:          DO I = MP1,N,4
  128:             DY(I) = DY(I) + DA*DX(I)
  129:             DY(I+1) = DY(I+1) + DA*DX(I+1)
  130:             DY(I+2) = DY(I+2) + DA*DX(I+2)
  131:             DY(I+3) = DY(I+3) + DA*DX(I+3)
  132:          END DO
  133:       ELSE
  134: *
  135: *        code for unequal increments or equal increments
  136: *          not equal to 1
  137: *
  138:          IX = 1
  139:          IY = 1
  140:          IF (INCX.LT.0) IX = (-N+1)*INCX + 1
  141:          IF (INCY.LT.0) IY = (-N+1)*INCY + 1
  142:          DO I = 1,N
  143:           DY(IY) = DY(IY) + DA*DX(IX)
  144:           IX = IX + INCX
  145:           IY = IY + INCY
  146:          END DO
  147:       END IF
  148:       RETURN
  149: *
  150: *     End of DAXPY
  151: *
  152:       END