
<span class='no'>mixedCPRs</span> <span class='kw'>&lt;-</span> <span class='fu'>c</span>(<span class='no'>CPRs</span>, <span class='no'>nonCPRs</span>)

<span class='co'>#identify problem</span>
<span class='fu'>isCPR</span>(<span class='no'>CPRs</span>)</div><div class='output co'>#&gt; Warning: The variable seems to consist of Danish civil regristration (CPR) numbers.</div><div class='input'>
<span class='co'>#no problem as there are no CPRs</span>
<span class='fu'>isCPR</span>(<span class='no'>nonCPRs<