4>Type requirements</h4>
<ul>
<li><code>T1/T2</code> is a model of <a href=
"expression_concept.htm#scalar_expression">Scalar Expression</a> .</li>
<li><code>E2/E1</code> is a model of <a href=
"expression_concept.htm#vector_expression">Vector Expression</a> .</li>
</ul>
<h4>Preconditions</h4>
<p>None.</p>
<h4>Complexity</h4>
<p>Linear depending from the size of the vector expression.</p>
<h4>Examples</h4>
<pre>
#include &lt;boost/numeric/ublas/vector.hpp&gt;
#include &lt;boost/numeric/ublas/io.hpp&gt;

int