o the
same group. If 2 groups exist, significantly altered time trajectories
can be identified. If no group or more than 2 groups are provided, the
trajectories can be plotted but significance cannot be calculated.</p>
</blockquote>
<p><code>data</code> and <code>metadata</code> information can be stored
as vectors, in one or in two separate Data.Frame. If a data-point is not
available (no data value for any variables) the row should be discarded.
If some of the variable measurements are missing for a given