code: def has_level_label(label_flags, vmin):
      
      if label_flags.size == 0 or (label_flags.size == 1 and
                                   label_flags[0] == 0 and
                                   vmin % 1 > 0.0):
          return False
      else:
          return True
docs: Returns true if the ``label_flags`` indicate there is at least one label
      for this level.
  
      if the minimum view limit is not an exact integer, then the first tick
      label won't be shown, so we must adjust for that.