2 type_of `tuple_hypermap`;;
6 (* restriction of a function to a domain, identity outside domain *)
8 let restrict = define `restrict (f:A->A) X = (\x. if (X x) then (f x) else x)`;;
10 (* essentailly the same as fan.ml set_of_edges
12 let edge_at = define `edge_at (V,E) v = { w | E {v,w} }`;; (* set_of_edges v E *)
16 define `dart_set (V,E) = ({(v,v) | set_of_edges v E = EMPTY} UNION {(v,w) | E {v,w} })`;;
18 (* check order of args in sigma_fan fan.ml *)
21 define `face_map_of_fan' (V,E) (v,w) =
22 if (E {v,w}) then (w,inverse_sigma_fan (vec 0) V E w v) else (v,w)`;;
25 define `edge_map_of_fan (V,E) (v,w) = (w,v)`;;
28 define `node_map_of_fan (V,E) (v,w) = (v,sigma_fan (vec 0) V E v w)`;;
32 let hyp_of_fano = define `hyp_of_fano (V,E) =
33 (let D = dart_set (V,E) in
34 hypermap( D ,(restrict (edge_map_of_fan (V,E)) D ) ,
35 (restrict (node_map_of_fan (V,E)) D) ,
36 (restrict (face_map_of_fan (V,E)) D) ))`;;