<pre class="sourceCode r"><code class="sourceCode r"><span class="kw">library</span>(planar)
<span class="kw">library</span>(ggplot2)
<span class="kw">require</span>(reshape2)
<span class="kw">library</span>(gridExtra)
<span class="kw">require</span>(plyr)</code></pre></div>
</div>
<div id="modelling-the-reflectivity" class="section level4">
<h4 class="hasAnchor">
<html><body><a href="#modelling-the-reflectivity" class="anchor"> </a></body></html>Modelling the reflectivity</h4>
<div class="sourceCode"><pre 