code: def fixPoint(self, plotterPoint, canvasPoint):
          'adjust visibleBox.xymin so that canvasPoint is plotted at plotterPoint'
          self.visibleBox.xmin = canvasPoint.x - self.canvasW(plotterPoint.x-self.plotviewBox.xmin)
          self.visibleBox.ymin = canvasPoint.y - self.canvasH(plotterPoint.y-self.plotviewBox.ymin)
          self.refresh(f fixPoint(self, plotterPoint, canvasPoint):
          'adjust visibleBox.xymin so that canvasPoint is plotted at plotterPoint'
          self.visibleBox.xmin = canvasPoint.x - self.canvasW(plotterPoint.x-self.plotviewBox.xmin)
          self.visibleBox.ymin = canvasPoint.y - self.canvasH(plotterPoint.y-self.plotviewBox.ymin)
          self.refresh()
docs: adjust visibleBox.xymin so that canvasPoint is plotted at plotterPoint