="op">)</span>,</span>
<span>              group <span class="op">=</span> <span class="fu"><a href="https://rdrr.io/r/base/interaction.html" class="external-link">interaction</a></span><span class="op">(</span><span class="va">year</span>,<span class="va">id</span><span class="op">)</span>,</span>
<span>              x_major <span class="op">=</span> <span class="va">long</span>, y_major <span class="op">=</span> <span class="va">lat</span>,</span>
<span>              x_minor <span class="op">=</span> <spa