rix as a vector. For example,</p>
<pre><code>matrix[10, 10] a = ...;
vector b = sub_col(a, 2, 3, 5);</code></pre>
<p>will set <code>b</code> equal to the vector <code>a[2:6, 3]</code>, taking the element starting at [2, 3], then extending for a total of 5 rows. The function <code>sub_row</code> works the same way for extracting a slice of a row as a row vector. For example, <code>sub_row(a, 2, 3, 5)</code> is equal to the row vector <code>a[2, 3:7]</code>, which also starts at position [2, 3] then extends f