chor" id="examples"><a class="anchor" href="#examples"></a>Examples</h2>
    <pre class="examples"><div class='input'>
<span class='fu'>data</span>(<span class='no'>smokehealth</span>)
<span class='no'>m</span> <span class='kw'>&lt;-</span> <span class='no'>smokehealth</span>
<span class='no'>m</span>[,<span class='fl'>3</span>] <span class='kw'>&lt;-</span> <span class='no'>m</span>[,<span class='fl'>3</span>]+ <span class='no'>m</span>[,<span class='fl'>4</span>]
<span class='no'>m</span>[<span class='fl'