Press or to move the cursor along the graph from one plotted point to the next.
If tracing a graph takes the cursor off the display screen
to the left or right, the viewing window pans to show the new cursor
location. The window settings are updated accordingly.
If tracing a graph takes the cursor off the display screen to the top or bottom, the cursor disappears from the screen. However, the x and y coordinates of the cursor are displayed at the bottom of the screen.
Press to adjust the viewing window so that the cursor location becomes the center of the window.