e fitted line),
`<font color="#82140F"><code>..R2..</code></font>' (the correlation coefficient).
</ul>
<p>
To see the values of the built-in variables (along with the user
variables), use `<font color="#82140F"><code>show variables</code></font>'.  Here are some useful builtin
variables: 
<p>
<ul>
<p>
<li> `<font color="#82140F"><code>..arrowsize..</code></font>'
<!-- latex: \index{@code{..arrowsize..}, size of arrows} -->
Stores either a positive number representing the halfwidth of arrowheads
measured in