matrix, so is <code>m[2:4]</code>. In contrast, supplying a single index, <code>m[3]</code>, produces a row vector result. That is, <code>m[3]</code> produces the same result as <code>m[3, ]</code> or <code>m[3, 1:cols(m)]</code>.</p>
</section>
<section id="arrays-of-vectors-or-matrices" class="level3 unnumbered">
<h3 class="unnumbered anchored" data-anchor-id="arrays-of-vectors-or-matrices">Arrays of vectors or matrices</h3>
<p>With arrays of matrices, vectors, and row vectors, the basic access rules rema