alues</dt>
<dd><p>Should the value be column-bound to the matrix</p></dd>


<dt>units</dt>
<dd><p>Should the indices be in xyz-coordinates or millimeters.</p></dd>

</dl></div>
    <div id="value">
    <h2>Value</h2>
    

<p>Matrix of 3 columns if <code>add_values = FALSE</code> or 4 columns, 
otherwise.</p>
    </div>

    <div id="ref-examples">
    <h2>Examples</h2>
    <div class="sourceCode"><pre class="sourceCode r"><code><span class="r-in"><span><span class="fu"><a href="https://rdrr.io/r/base/Rando