="dt">colour =</span> <span class="kw">guide_legend</span>())

## colour map
p2 &lt;-<span class="st"> </span><span class="kw">ggplot</span>(d2) +<span class="st"> </span><span class="kw">geom_raster</span>(<span class="kw">aes</span>(angle *<span class="st"> </span><span class="dv">180</span>/pi, thickness, <span class="dt">fill =</span> R)) +<span class="st"> </span><span class="kw">scale_y_continuous</span>(<span class="st">"thickness"</span>, 
    <span class="dt">expand =</span> <span class="kw">c</spa