"dt">key =</span> <span class="st">&quot;sensor&quot;</span>, <span class="dt">value =</span> <span class="st">&quot;value&quot;</span>, x, y, z)

<span class="kw">ggplot</span>(d, <span class="kw">aes</span>(timestamp, value)) <span class="op">+</span><span class="st"> </span><span class="kw">geom_line</span>() <span class="op">+</span><span class="st"> </span>
<span class="st">  </span><span class="kw">geom_hline</span>(<span class="dt">yintercept =</span> <span class="dv">0</span>, <span class="dt">linet