iterator is a public type declared by Vector&lt;T_numtype&gt;, and
should be used to specify the type of the iterator:
<pre>
Vector&lt;double&gt; x(50);
Vector&lt;double&gt;::T_iterator iter = x.begin();
</pre>
Since T_iterator is STL-compliant, it may be used with the standard
template library routines.  [GIVE EXAMPLES]  See also end().
</li>

<br><br><li>
<b>T_constIterator begin()  const</b>    ** NOT YET SUPPORTED<br><br>
Returns an STL-compliant const iterator positioned at the beginning of
the vector'