
(%o2) F(x) := (charfun(x &gt;= 9) + charfun(x &gt;= 8)
               + 3 charfun(x &gt;= 7) + charfun(x &gt;= 5)
               + 2 charfun(x &gt;= 3) + charfun(x &gt;= 1))/9
(%i3) F(6);
                           4
(%o3)                      -
                           9
(%i4) load(draw)$
(%i5) draw2d(
        line_width = 3,
        grid       = true,
        explicit(F(z), z, -2, 12)) $
</pre>
</dd></dl>



<dl>
<dt><u>Función:</u> <b>cov</b><i> (<var>matrix</var>)</i>
<a name="IDX1677"></a>
</dt>
<d