heck</code>: Default = FALSE. If TRUE data matrix and arguments are not checked - this saves time e.g. when you use this function for simulations.</p></li>
</ul></td>
    </tr>
    <tr>
      <th>x</th>
      <td><p>an object of class <code>gpcm4pl</code> which is the result of using the <code>PPall()</code> function</p></td>
    </tr>
    <tr>
      <th>...</th>
      <td><p>just some points.</p></td>
    </tr>
    <tr>
      <th>object</th>
      <td><p>An object of class <code>gpcm4pl</code> which is the