class_docstr: Click on a point to select and highlight it -- the data that
  generated the point will be shown in the lower Axes.  Use the 'n'
  and 'p' keys to browse through the next and previous points
class_docstr_tok: ["Click","on","a","point","to","select","and","highlight","it","--","the","data","that","generated","the","point","will","be","shown","in","the","lower","Axes",".","Use","the","'n'","and","'","p","'","keys","to","browse","through","the","next","and","previous","points"]
code: def update(self):
      if self.lastind is None:
          return
  
      dataind = self.lastind
  
      ax2.clear()
      ax2.plot(X[dataind])
  
      ax2.text(
          0.05,
          0.9,
          f"mu={xs[dataind]:1.3f}\nsigma={ys[dataind]:1.3f}",
          transform=ax2.transAxes,
          va="top",
      )
      ax2.set_ylim(-0.5, 1.5)
      self.selected.set_visible(True)
      self.selected.set_data(xs[dataind], ys[dataind])
  
      self.text.set_text("selected: %d" % dataind)
      fig.canvas.draw()
  
imports: import numpy
label_desc: Use image node_id 4 for calling the PointBrowser obj's underlying member method code with example usage: obj.update() without return types