 id="arg-ll-digits">ll_digits<a class="anchor" aria-label="anchor" href="#arg-ll-digits"></a></dt>
<dd><p>integer; the number of digits to round latitude and longitude
to. If latitude and/or longitude are used as <code>site_vars</code>, it's usually best
to round them prior to identifying sites, otherwise locations that are only
slightly offset (e.g. a few centimeters) will be treated as different. This
argument can also be used to group sites together that are close but not
identical. Note that 1 degree of