http://franz.com/ns/allegrograph/4.11/sna/size
Retrieve the size of an SNA group, etc.
The pattern is used as:
  ?thing sna:size ?size .    This will bind  ?size  to the number of elements in  ?thing .  ?thing  can be bound to an SNA group (cf. egoGroup) or a path. 
Notes
The following namespace abbreviations are used:
- fti - <http://franz.com/ns/allegrograph/2.2/textindex/>
 - geo - <http://franz.com/ns/allegrograph/3.0/geospatial/>
 - geofn - <http://franz.com/ns/allegrograph/3.0/geospatial/fn/>
 - nd - <http://franz.com/ns/allegrograph/5.0/geo/nd#>
 - ndfn - <http://franz.com/ns/allegrograph/5.0/geo/nd/fn#>
 - sna - <http://franz.com/ns/allegrograph/4.11/sna/>
 
The SPARQL magic properties reference has additional information on using AllegroGraph magic properties and functions.