eturns the Jacobi elliptic function <span class="emphasis"><em>nc</em></span>.
        </p>
<p>
          The final <a class="link" href="../../policy.html" title="Policies">Policy</a> argument is
          optional and can be used to control the behaviour of the function: how
          it handles errors, what level of precision to use etc. Refer to the <a class="link" href="../../policy.html" title="Policies">policy documentation for more details</a>.
        </p>
<p>
          This function is a trivial w