gap&gt; pg := PG(7,8^2);
ProjectiveSpace(7, 64)
gap&gt; sub := CanonicalSubgeometryOfProjectiveSpace(pg,8);
Subgeometry PG(7, 8) of ProjectiveSpace(7, 64)
gap&gt; ProjectiveDimension(sub);
7
gap&gt; Dimension(sub);
7
gap&gt; Rank(sub);
7
