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Première mise à jour de lapack et blas.

    1: *> \brief \b DROT
    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 DROT(N,DX,INCX,DY,INCY,C,S)
   12: *
   13: *       .. Scalar Arguments ..
   14: *       DOUBLE PRECISION C,S
   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: *>    DROT applies a plane rotation.
   28: *> \endverbatim
   29: *
   30: *  Arguments:
   31: *  ==========
   32: *
   33: *> \param[in] N
   34: *> \verbatim
   35: *>          N is INTEGER
   36: *>         number of elements in input vector(s)
   37: *> \endverbatim
   38: *>
   39: *> \param[in,out] DX
   40: *> \verbatim
   41: *>          DX is DOUBLE PRECISION array, dimension ( 1 + ( N - 1 )*abs( INCX ) )
   42: *> \endverbatim
   43: *>
   44: *> \param[in] INCX
   45: *> \verbatim
   46: *>          INCX is INTEGER
   47: *>         storage spacing between elements of DX
   48: *> \endverbatim
   49: *>
   50: *> \param[in,out] DY
   51: *> \verbatim
   52: *>          DY is DOUBLE PRECISION array, dimension ( 1 + ( N - 1 )*abs( INCY ) )
   53: *> \endverbatim
   54: *>
   55: *> \param[in] INCY
   56: *> \verbatim
   57: *>          INCY is INTEGER
   58: *>         storage spacing between elements of DY
   59: *> \endverbatim
   60: *>
   61: *> \param[in] C
   62: *> \verbatim
   63: *>          C is DOUBLE PRECISION
   64: *> \endverbatim
   65: *>
   66: *> \param[in] S
   67: *> \verbatim
   68: *>          S is DOUBLE PRECISION
   69: *> \endverbatim
   70: *
   71: *  Authors:
   72: *  ========
   73: *
   74: *> \author Univ. of Tennessee
   75: *> \author Univ. of California Berkeley
   76: *> \author Univ. of Colorado Denver
   77: *> \author NAG Ltd.
   78: *
   79: *> \ingroup double_blas_level1
   80: *
   81: *> \par Further Details:
   82: *  =====================
   83: *>
   84: *> \verbatim
   85: *>
   86: *>     jack dongarra, linpack, 3/11/78.
   87: *>     modified 12/3/93, array(1) declarations changed to array(*)
   88: *> \endverbatim
   89: *>
   90: *  =====================================================================
   91:       SUBROUTINE DROT(N,DX,INCX,DY,INCY,C,S)
   92: *
   93: *  -- Reference BLAS level1 routine --
   94: *  -- Reference BLAS is a software package provided by Univ. of Tennessee,    --
   95: *  -- Univ. of California Berkeley, Univ. of Colorado Denver and NAG Ltd..--
   96: *
   97: *     .. Scalar Arguments ..
   98:       DOUBLE PRECISION C,S
   99:       INTEGER INCX,INCY,N
  100: *     ..
  101: *     .. Array Arguments ..
  102:       DOUBLE PRECISION DX(*),DY(*)
  103: *     ..
  104: *
  105: *  =====================================================================
  106: *
  107: *     .. Local Scalars ..
  108:       DOUBLE PRECISION DTEMP
  109:       INTEGER I,IX,IY
  110: *     ..
  111:       IF (N.LE.0) RETURN
  112:       IF (INCX.EQ.1 .AND. INCY.EQ.1) THEN
  113: *
  114: *       code for both increments equal to 1
  115: *
  116:          DO I = 1,N
  117:             DTEMP = C*DX(I) + S*DY(I)
  118:             DY(I) = C*DY(I) - S*DX(I)
  119:             DX(I) = DTEMP
  120:          END DO
  121:       ELSE
  122: *
  123: *       code for unequal increments or equal increments not equal
  124: *         to 1
  125: *
  126:          IX = 1
  127:          IY = 1
  128:          IF (INCX.LT.0) IX = (-N+1)*INCX + 1
  129:          IF (INCY.LT.0) IY = (-N+1)*INCY + 1
  130:          DO I = 1,N
  131:             DTEMP = C*DX(IX) + S*DY(IY)
  132:             DY(IY) = C*DY(IY) - S*DX(IX)
  133:             DX(IX) = DTEMP
  134:             IX = IX + INCX
  135:             IY = IY + INCY
  136:          END DO
  137:       END IF
  138:       RETURN
  139: *
  140: *     End of DROT
  141: *
  142:       END