the Gudermannian function.
        </li>
        <li>
          <b>HERMITE_POLY</b> evaluates the Hermite polynomials at X.
        </li>
        <li>
          <b>HERMITE_POLY_COEF</b> evaluates the Hermite polynomial coefficients.
        </li>
        <li>
          <b>HERMITE_POLY_VALUES</b> returns some values of the Hermite polynomial.
        </li>
        <li>
          <b>HYPER_2F1_VALUES</b> returns some values of the hypergeometric function 2F1.
        </li>
        <li>
          <b>I4_CHOOSE</