span> <span class="dv">500</span>), <span class="dt">polarisation =</span> <span class="st">"p"</span>)
    <span class="kw">data.frame</span>(results[<span class="kw">c</span>(<span class="st">"angle"</span>, <span class="st">"R"</span>)])
    
}

## loop over parameters
parameters &lt;-<span class="st"> </span>function(<span class="dt">res =</span> <span class="dv">10</span>) <span class="kw">data.frame</span>(<span class="dt">thickness =</span> <span class="kw">seq</span>(<span class="dv">0</span>, <span