code: def set_viewlimits(self, panel='top'):
          
          this_panel = self.get_panel(panel)
  
          xmin, xmax, ymin, ymax = this_panel.conf.set_viewlimits()[0]
          # print("Set ViewLimits ", xmin, xmax, ymin, ymax)
          # make top/bottom panel follow xlimits
          if this_panel == self.panel:
              other = self.panel_bot
              for _ax in other.fig.get_axes():
                  _ax.set_xlim((xmin, xmax), emit=True)
              other.draw()
docs: update xy limits of a plot, as used with .update_line()