principal cube root of a C4.
        </li>
        <li>
          <b>C4_DIV</b> divides two C4's.
        </li>
        <li>
          <b>C4_DIV_R8</b> divides a C4 by an R8.
        </li>
        <li>
          <b>C4_EXP</b> evaluates the exponential of a C4.
        </li>
        <li>
          <b>C4_I</b> returns the the imaginary unit, i as a C4.
        </li>
        <li>
          <b>C4_IMAG</b> evaluates the imaginary part of a C4.
        </li>
        <li>
          <b>C4_INV</b> evaluates the inve