Auto Redraw
Check the View | Redraw | Auto Redraw command to automatically redraw the plot window each time the window contents are changed. The Auto Redraw option is on by default, and this is indicated by a check mark next to the command. Select the View | Redraw | Auto Redraw command to toggle the command on and off. If Auto Redraw is unchecked, use the View | Redraw | Redraw command or press the F5 key on the keyboard to redraw the image.