code: def valueAt( self, pos ):
          
          if ( self.orientation() == Qt.Horizontal ):
              perc = (self.width() - 4 - pos) / float(self.width())
          else:
              perc = (self.height() - 4 - pos) / float(self.height())
          
          start = self.minimum()
          end   = self.maximum()
          
          return round((end - start) * (1 - perc))
docs: Returns the value for the slider at the inputed position.
          
          :param      pos | <int>
          
          :return     <int>