n array of size 3 containing vectors with 7
elements. Arrays may also contain matrices. The example</p>
<pre class="stan"><code>array[15, 12] matrix[7, 2] mu;</code></pre>
<p>declares a 15 by 12 array of <span class="math inline">\(7 \times 2\)</span> matrices. Any of the
constrained types may also be used in arrays, as in the declaration</p>
<pre class="stan"><code>array[2, 3, 4] cholesky_factor_cov[5, 6] mu;</code></pre>
<p>of a <span class="math inline">\(2 \times 3 \times 4\)</span> array of <span class