 number of dimensions,
and that we can order the components of the state vector x like this:

   x  =  &lt;x_1, x_2, ..., x_p, x_(p+1), ..., x_(p+q)&gt;.

In other words, the components of state fall into two camps,
with the first camp having a rank of p and the second camp
having a rank of q.  Here, &quot;rank&quot; is just a 4-letter word
that economizes for the 6-syllable word &quot;dimensionality&quot;.

In this speculative scenario, let's say we have good reason to call
the first camp of components the