Hey Michael, > Some more questions on Gremlin :-)
Ha. There is a Gremlin mailing list if you are **super** interested :). http://groups.google.com/group/gremlin-users ... However, don't even try and join unless you are !!!!SUPER!!!! interested. :P > It is important to note that in Gremlin, vertices are adjacent to > edges and edges are adjacent to vertices. > > Well - isn't that in the nature of the graph? As far as my understanding > goes, there is no such thing as vertex on vertex, or edge to edge. It's > always an edge between two vertices, and alway a vertex between two > edges. Navigating the graph means alternately traversing vertices and > edges. Unless I'm mistaken, that is. Exactly. People tend to forget this point---thats why I stress it. Vertices are adjacent to edges and edges are adjacent to vertices. HyperGraphDB [ http://www.kobrix.com/hgdb.jsp ] throws that distinction out of the water and says all there is are 'atoms' and 'atoms' can be adjacent to each other. By making a distinction between edges and vertices, you are saying that an edge is a binary relationship between two vertices---this makes it a regular graph as opposed to a hypergraph. Neo4j/Gremlin/RDF/and_lots_others are regular graphs. > I understand outE, inE and bothE. Edges may have a direction (or two, or > none - depending on the point of view), so in/out/both looks like the > logical thing to do. > > But what about outV and inV? Vertices aren't directional, are they? Yea---outV means "the outgoing vertex from the edge" (the tail of the edge). inV means "the incoming vertex of the edge" (the head of the edge). In Neo4j speak, its startNode and endNode, respectively. See ya, Marko. http://markorodriguez.com _______________________________________________ Neo mailing list User@lists.neo4j.org https://lists.neo4j.org/mailman/listinfo/user
