def plot(self,axis=None,**kargs):
        """
        - plot(axis=None, **kwarg): Finally, sphviewer.Scene class has its own plotting method. 
        It shows the scene as seen by the camera. It is to say, it plots the particles according
        to their aparent coordinates; axis makes a reference to an existing axis. In case axis is None,
        the plot is made on the current axis.

        The kwargs are :class:`~matplotlib.lines.Line2D` properties:

        agg_filter: unknown
        alpha: float (0.0 transparent through 1.0 opaque)         
        animated: [True | False]         
        antialiased or aa: [True | False]         
        axes: an :class:`~matplotlib.axes.Axes` instance         
        clip_box: a :class:`matplotlib.transforms.Bbox` instance         
        clip_on: [True | False]         
        clip_path: [ (:class:`~matplotlib.path.Path`,         :class:`~matplotlib.transforms.Transform`) |         :class:`~matplotlib.patches.Patch` | None ]         
        color or c: any matplotlib color         
        contains: a callable function         
        dash_capstyle: ['butt' | 'round' | 'projecting']         
        dash_joinstyle: ['miter' | 'round' | 'bevel']         
        dashes: sequence of on/off ink in points         
        data: 2D array (rows are x, y) or two 1D arrays         
        drawstyle: [ 'default' | 'steps' | 'steps-pre' | 'steps-mid' | 'steps-post' ]         
        figure: a :class:`matplotlib.figure.Figure` instance         
        fillstyle: ['full' | 'left' | 'right' | 'bottom' | 'top']         
        gid: an id string         
        label: any string         
        linestyle or ls: [ ``'-'`` | ``'--'`` | ``'-.'`` | ``':'`` | ``'None'`` | ``' '`` | ``''`` ]         and any drawstyle in combination with a linestyle, e.g. ``'steps--'``.         
        linewidth or lw: float value in points         
        lod: [True | False]         
        marker: [ ``7`` | ``4`` | ``5`` | ``6`` | ``'o'`` | ``'D'`` | ``'h'`` | ``'H'`` | ``'_'`` | ``''`` | ``'None'`` | ``' '`` | ``None`` | ``'8'`` | ``'p'`` | ``','`` | ``'+'`` | ``'.'`` | ``'s'`` | ``'*'`` | ``'d'`` | ``3`` | ``0`` | ``1`` | ``2`` | ``'1'`` | ``'3'`` | ``'4'`` | ``'2'`` | ``'v'`` | ``'<'`` | ``'>'`` | ``'^'`` | ``'|'`` | ``'x'`` | ``'$...$'`` | *tuple* | *Nx2 array* ]
        markeredgecolor or mec: any matplotlib color         
        markeredgewidth or mew: float value in points         
        markerfacecolor or mfc: any matplotlib color         
        markerfacecoloralt or mfcalt: any matplotlib color         
        markersize or ms: float         
        markevery: None | integer | (startind, stride)
        picker: float distance in points or callable pick function         ``fn(artist, event)``         
        pickradius: float distance in points         
        rasterized: [True | False | None]         
        snap: unknown
        solid_capstyle: ['butt' | 'round' |  'projecting']         
        solid_joinstyle: ['miter' | 'round' | 'bevel']         
        transform: a :class:`matplotlib.transforms.Transform` instance         
        url: a url string         
        visible: [True | False]         
        xdata: 1D array         
        ydata: 1D array         
        zorder: any number         
        
        kwargs *scalex* and *scaley*, if defined, are passed on to
        :meth:`~matplotlib.axes.Axes.autoscale_view` to determine
        whether the *x* and *y* axes are autoscaled; the default is
        *True*.
        
        Additional kwargs: hold = [True|False] overrides default hold state
        """
        if(axis == None):
            axis = plt.gca()
        axis.plot(self.__x, self.__y, 'k.', **kargs)