ch contain only function definitions (intended for use with <code>#include</code>) should be given the <code>.stanfunctions</code> extension. A <code>.stanfunctions</code> file only includes the function definition and does not require the <code>functions{}</code> block wrapped around the function. A simple example of usage where the function is defined and saved in the file <code>foo.stanfunctions</code>:</p>
<div class="sourceCode" id="cb1"><pre class="sourceCode stan code-with-copy"><code class="sourceCo