#open database pgraph2;
#query meminit (1524);
#query p2 loadgraph;

# Queries the top 5 co-authors publications of "Ralf Hartmut Gueting" 
# The results will be grouped and show the Authors with the sum of
# joint publications.

# The starting nodes for the subgraph match are taken from the
# tuple stream (first argument).
# Note the direction argument "<-" to match an edge in reverse direction.

query p2
   Author feed
match1 ['
(  
   ( Author  ( (Name "Ralf Hartmut Gueting") ) )
   AUTHOR_OF
   ( (doc Document) 
     AUTHOR_OF <-
     ( (a Author) )
   )
)',
'( ((a Name) <> "Ralf Hartmut Gueting") )',
'(  ((a Name) Name)  )'
] 
sortby[Name] groupby[Name; Cnt:group count] sortby[Cnt:desc] head[5] consume;