title: How to explicitly create a function template
body: <p><strong>modbus.hpp</strong></p>
  <pre class="lang-cpp prettyprint-override"><code>class modbus_rtu
  {
      template &lt;typename T&gt;
      T round ( T var, T scale );
  };
  </code></pre>
  <p><strong>modbus.cpp</strong></p>
  <pre class="lang-cpp prettyprint-override"><code>template &lt;typename T&gt;
  T modbus_rtu::round ( T var, T scale )
  {
      return std::round( var / scale ) * scale;
  }
  </code></pre>
  <p>I know I need to explicitly create a function template, but I forgot exactly how it is done.
  Please tell me where and exactly how to add the function template. Calling with types:<code>double, float</code>.</p>