A nice scale will be selected
automatically.  (You can change this or any other plot characteristics
easily, as you'll see later.)
<li>
`<font color="#82140F"><code>draw title</code></font>' tells Gri to write the indicated string
centered above the plot. The title <b>must</b> be enclosed in quotes.
<li>
`<font color="#82140F"><code>quit</code></font>' tells Gri to exit.
</ul>
<p>
Gri will draw axes automatically, and pick its own scales.
<p>
If you wish to draw several curves which cross each other, you sh