ples"></a>Examples</h2>
    <pre class="examples"><div class='input'><span class='fu'><a href='https://www.rdocumentation.org/packages/base/topics/library'>library</a></span>(<span class='no'>data.table</span>)
<span class='no'>dt</span> <span class='kw'>&lt;-</span> <span class='fu'><a href='https://www.rdocumentation.org/packages/data.table/topics/data.table'>data.table</a></span>(<span class='kw'>x1</span> <span class='kw'>=</span> <span class='fl'>1</span>, <span class='kw'>x2</span> <span class='kw'>=<