I'm plotting some data in a Tkinter FigureCanvasTkagg using matplotlib. I need to clear the figure where i plot data and draw new data when a button is pressed. here is the plotting part of the code (there's an App class defined before..)

    self.fig = figure()
    self.ax = self.fig.add_subplot(111)
    self.ax.set_ylim( min(y), max(y) )      

    self.line, = self.ax.semilogx(x,y,'.-')   #tuple of a single element
    self.canvas = FigureCanvasTkAgg(self.fig,master=master)
    self.ax.semilogx(x,y,'o-')
    self.canvas.show()
    self.canvas.get_tk_widget().pack(side='top', fill='both', expand=1)
    self.frame.pack()   

how do i update the contents of such a canvas?

regards,

Jacopo