Pagerank in Gremlin

$_g := neo4j:open('neodb.neo')
$bob := g:add-v(g:map('name','Bob'))
$john := g:add-v(g:map('name','John'))
$alice := g:add-v(g:map('name','Alice'))
$e1 := g:add-e($bob,'link',$john)
$e2 := g:add-e($john,'link',$alice)
$e3 := g:add-e($alice,'link',$bob)
$e1/weight := 10
$e2/weight := 1
$e3/weight := 20

$res := jung:pagerank(g:map('link',g:list('link'),'filter',true(),'alpha', 0.15, 'weight-key', 'weight')) 
foreach $key in g:keys($res)
	 $key/@pagerank := g:get($res, $key)
end