code: def update(self, points, values=None):
          
          self.values = values or [None] * len(points)
  
          if np is None:
              if self.option.function:
                  warnings.warn('numpy not available, function ignored')
              self.points = points
              self.minimum = min(self.points)
              self.maximum = max(self.points)
              self.current = self.points[-1]
  
          else:
              self.points = self.apply_function(points)
              self.minimum = np.min(self.points)
              self.maximum = np.max(self.points)
              self.current = self.points[-1]
  
          if self.maximum == self.minimum:
              self.extents = 1
          else:
              self.extents = (self.maximum - self.minimum)
              self.extents = (self.maximum - self.minimum)
docs: Add a set of data points.