gap&gt; ps := SymplecticSpace(5,7);
W(5, 7)
gap&gt; p := Random(Points(ps));
&lt;a point in W(5, 7)&gt;
gap&gt; plane := Random(Planes(p));
&lt;a plane in W(5, 7)&gt;
gap&gt; flag := FlagOfIncidenceStructure(ps,[p,p,plane]);
&lt;a flag of W(5, 7) &gt;
gap&gt; Size(flag);
2
gap&gt; ElementsOfFlag(flag);
[ &lt;a point in W(5, 7)&gt;, &lt;a plane in W(5, 7)&gt; ]
