Return to zswap.f CVS log

Up to [local] / rpl / lapack / blas

Première mise à jour de lapack et blas.

    1: *> \brief \b ZSWAP
    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 ZSWAP(N,ZX,INCX,ZY,INCY)
   12: *
   13: *       .. Scalar Arguments ..
   14: *       INTEGER INCX,INCY,N
   15: *       ..
   16: *       .. Array Arguments ..
   17: *       COMPLEX*16 ZX(*),ZY(*)
   18: *       ..
   19: *
   20: *
   21: *> \par Purpose:
   22: *  =============
   23: *>
   24: *> \verbatim
   25: *>
   26: *>    ZSWAP interchanges two vectors.
   27: *> \endverbatim
   28: *
   29: *  Arguments:
   30: *  ==========
   31: *
   32: *> \param[in] N
   33: *> \verbatim
   34: *>          N is INTEGER
   35: *>         number of elements in input vector(s)
   36: *> \endverbatim
   37: *>
   38: *> \param[in,out] ZX
   39: *> \verbatim
   40: *>          ZX is COMPLEX*16 array, dimension ( 1 + ( N - 1 )*abs( INCX ) )
   41: *> \endverbatim
   42: *>
   43: *> \param[in] INCX
   44: *> \verbatim
   45: *>          INCX is INTEGER
   46: *>         storage spacing between elements of ZX
   47: *> \endverbatim
   48: *>
   49: *> \param[in,out] ZY
   50: *> \verbatim
   51: *>          ZY is COMPLEX*16 array, dimension ( 1 + ( N - 1 )*abs( INCY ) )
   52: *> \endverbatim
   53: *>
   54: *> \param[in] INCY
   55: *> \verbatim
   56: *>          INCY is INTEGER
   57: *>         storage spacing between elements of ZY
   58: *> \endverbatim
   59: *
   60: *  Authors:
   61: *  ========
   62: *
   63: *> \author Univ. of Tennessee
   64: *> \author Univ. of California Berkeley
   65: *> \author Univ. of Colorado Denver
   66: *> \author NAG Ltd.
   67: *
   68: *> \ingroup complex16_blas_level1
   69: *
   70: *> \par Further Details:
   71: *  =====================
   72: *>
   73: *> \verbatim
   74: *>
   75: *>     jack dongarra, 3/11/78.
   76: *>     modified 12/3/93, array(1) declarations changed to array(*)
   77: *> \endverbatim
   78: *>
   79: *  =====================================================================
   80:       SUBROUTINE ZSWAP(N,ZX,INCX,ZY,INCY)
   81: *
   82: *  -- Reference BLAS level1 routine --
   83: *  -- Reference BLAS is a software package provided by Univ. of Tennessee,    --
   84: *  -- Univ. of California Berkeley, Univ. of Colorado Denver and NAG Ltd..--
   85: *
   86: *     .. Scalar Arguments ..
   87:       INTEGER INCX,INCY,N
   88: *     ..
   89: *     .. Array Arguments ..
   90:       COMPLEX*16 ZX(*),ZY(*)
   91: *     ..
   92: *
   93: *  =====================================================================
   94: *
   95: *     .. Local Scalars ..
   96:       COMPLEX*16 ZTEMP
   97:       INTEGER I,IX,IY
   98: *     ..
   99:       IF (N.LE.0) RETURN
  100:       IF (INCX.EQ.1 .AND. INCY.EQ.1) THEN
  101: *
  102: *       code for both increments equal to 1
  103:          DO I = 1,N
  104:             ZTEMP = ZX(I)
  105:             ZX(I) = ZY(I)
  106:             ZY(I) = ZTEMP
  107:          END DO
  108:       ELSE
  109: *
  110: *       code for unequal increments or equal increments not equal
  111: *         to 1
  112: *
  113:          IX = 1
  114:          IY = 1
  115:          IF (INCX.LT.0) IX = (-N+1)*INCX + 1
  116:          IF (INCY.LT.0) IY = (-N+1)*INCY + 1
  117:          DO I = 1,N
  118:             ZTEMP = ZX(IX)
  119:             ZX(IX) = ZY(IY)
  120:             ZY(IY) = ZTEMP
  121:             IX = IX + INCX
  122:             IY = IY + INCY
  123:          END DO
  124:       END IF
  125:       RETURN
  126: *
  127: *     End of ZSWAP
  128: *
  129:       END