<para>
This option specifies the maximum number of points that the radius filter may
keep.  If there are more than this number of points within the specified
distance of the center, the more distant points will be discarded even though
they are within the specified distance.  If this option is not specified,
all points are kept regardless of how many there are.
</para>
<para>
Note that if the <option>nosort</option> option is also specified, this
option will instead keep points based on their position within the input
file rather than on their distance from the center.  This may or may not be
what you want.
</para>
<para>
Note, too, that this option may be used with the <option>exclude</option>
option, but the results might not be what you expect.  In particular, the
results will not be the same as if you had kept all of the points you'd
otherwise throw away.  You will still get no more than
<varname>maxcount</varname> points, but they will all be at least
<varname>distance</varname> away from the center.  (And possibly sorted.)
</para>
