code: def setKnob(self, value):
      # Note, we ignore value arg here and just go by state of the params
      x1, y1, x2, y2 = self.compute(self.f0.value, self.A.value)
      # update the data of the two waveforms
      self.lines[0].set(xdata=x1, ydata=y1)
      self.lines[1].set(xdata=x2, ydata=y2)
      # make the canvas draw its contents again with the new data
      self.canvas.draw()
  
imports: import wx
  import numpy
  from matplotlib.backends.backend_wxagg import FigureCanvasWxAgg
  from matplotlib.figure import Figure
label_desc: Use image node_id 9 for calling the FourierDemoFrame obj's underlying member method code with example usage: obj.setKnob(value) without return types