        <p>
                    <a class="link" href="../nmp.html#math_toolkit.dist_ref.nmp.pdf">Probability Density
                    Function</a>
                  </p>
                </td>
<td>
                  <p>
                    The probability of obtaining <span class="bold"><strong>exactly k
                    failures</strong></span> from k+r trials with success fraction p.
                    For example:
                  </p>
<pre class="programlisting"><span class="identifier">pdf</span