Return to zswap.f CVS log

Up to [local] / rpl / lapack / blas

En route vers la 4.4.1.

    1:       SUBROUTINE ZSWAP(N,ZX,INCX,ZY,INCY)
    2: *     .. Scalar Arguments ..
    3:       INTEGER INCX,INCY,N
    4: *     ..
    5: *     .. Array Arguments ..
    6:       DOUBLE COMPLEX ZX(*),ZY(*)
    7: *     ..
    8: *
    9: *  Purpose
   10: *  =======
   11: *
   12: *     ZSWAP interchanges two vectors.
   13: *
   14: *  Further Details
   15: *  ===============
   16: *
   17: *     jack dongarra, 3/11/78.
   18: *     modified 12/3/93, array(1) declarations changed to array(*)
   19: *
   20: *  =====================================================================
   21: *
   22: *     .. Local Scalars ..
   23:       DOUBLE COMPLEX ZTEMP
   24:       INTEGER I,IX,IY
   25: *     ..
   26:       IF (N.LE.0) RETURN
   27:       IF (INCX.EQ.1 .AND. INCY.EQ.1) THEN
   28: *
   29: *       code for both increments equal to 1
   30:          DO I = 1,N
   31:             ZTEMP = ZX(I)
   32:             ZX(I) = ZY(I)
   33:             ZY(I) = ZTEMP
   34:          END DO
   35:       ELSE
   36: *
   37: *       code for unequal increments or equal increments not equal
   38: *         to 1
   39: *
   40:          IX = 1
   41:          IY = 1
   42:          IF (INCX.LT.0) IX = (-N+1)*INCX + 1
   43:          IF (INCY.LT.0) IY = (-N+1)*INCY + 1
   44:          DO I = 1,N
   45:             ZTEMP = ZX(IX)
   46:             ZX(IX) = ZY(IY)
   47:             ZY(IY) = ZTEMP
   48:             IX = IX + INCX
   49:             IY = IY + INCY
   50:          END DO
   51:       END IF
   52:       RETURN
   53:       END