make it free software which everyone can redistribute and change under these terms.</p>
<p>To do so, attach the following notices to the program. It is safest to attach them to the start of each source file to most effectively state the exclusion of warranty; and each file should have at least the “copyright” line and a pointer to where the full notice is found.</p>
<div class="sourceCode" id="cb1"><pre class="sourceCode R"><code class="sourceCode r"><span id="cb1-1"><a href="#cb1-1" aria-hidden="true" 