code: def notches( self ):
          
          if ( self._notches is not None ):
              return self._notches
          
          rtype           = self.rulerType()
          formatter       = self.formatter()
          format          = self.format()
          self._notches   = []
          
          minimum = self.minimum()
          maximum = self.maximum()
          step    = self.step()
          
          if ( step <= 0 ):
              return []
          
          curr = minimum
          while ( curr < maximum ):
              self._notches.append(self.formatValue(curr))
              
              if ( rtype == XChartRuler.Type.Number ):
                  curr += step
              elif ( rtype == XChartRuler.Type.Date ):
                  curr = curr.addDays(step)
              elif ( rtype in (XChartRuler.Type.Datetime, XChartRuler.Type.Time)):
                  curr = curr.addSecs(step)
              else:
                  break
          
          self._notches.append(self.formatValue(maximum))
          
          return self._notches
docs: Reutrns a list of the notches that are going to be used for this ruler.
          If the notches have not been explicitly set (per a Custom type), then
          the notches will be generated based on the minimum, maximum and step
          values the current ruler type.
          
          :return     [<str>, ..]