Angelo,
no, A* is currently not exposed, mostly due to the fact that we couldn't
come up with a nice way to provide generic parameters over REST to it. You
can easily just expose it via a Plugin, see
http://docs.neo4j.org/chunked/milestone/server-plugins.html with the
parameters you need.

Regarding performance, Michael and I want to get the OSM import into a
shape where you actually can load Germany or Italy as a whole. Right now it
slows down a lot and we know that it is the Lucene Index lookups, we just
need to get a few more hours together to test our custom index for that :)

When you have the data in (try it with a smaller region) you should be able
to write your routing, but I think with OSM, a simple A* is not going to
cut it, since not all relationships are actually relevant for the routing
(e.g. you only want to count in WAYs etc), so I guess it takes some
thinking to come up with the right algo, or you extract a derived graph
that is just your routing-relevant info and maybe do your A* on that one?

/peter


G:  neubauer.peter
S:  peter.neubauer
P:  +46 704 106975
L:   http://www.linkedin.com/in/neubauer
T:   @peterneubauer

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On Fri, Jan 10, 2014 at 9:34 AM, Angelo Immediata <[email protected]>wrote:

> Hi there
>
> I'm using this environment:
>
>    - spring 3.2.6
>    - spring-data-neo4j 2.3.3 (I'm thinking to upgrade to the version 3 in
>    order to have support for neo4j 2.0)
>    - neo4j 1.9.5
>
>
> I'm thinking to use neo4j in order to store our own graph that will be
> used in a route planner project. The first question is if this seems to you
> (sure more experts than me) a good solution in order to build a very good
> and efficient and performant route planner
> Moreover as far as I know (by reading this link
> http://docs.neo4j.org/chunked/1.9.5/graph-algo.html ) in neo4j these
> algorithms are implemented:
>
>    - Shortest paths
>    - all paths
>    - all simple paths
>    - Dijkstra
>    - A*
>
>
> By reading this link
> http://docs.neo4j.org/chunked/1.9.5/rest-api-graph-algos.html I saw that
> REST API allows to call these algorithms:
>
>    - Find all shortest paths
>    - Find one of the shortest paths between nodes
>    - Execute a Dijkstra algorithm with similar weights on relationships
>    - Execute a Dijkstra algorithm with weights on relationships
>
>
> The second question is: can't I invoke the A* algorithm by REST API? This
> is related to the fact that I'ld love to have one (ore more) dedicated
> machine to neo4j and access to them by REST API (is this a good solution?)
>
> The last question regards neo4j performance. In my real scenario i may
> import an OSM file of an whole italian region (maybe also the full Italy);
> in the case of one region I can have around 10 millions of nodes (also more
> than 10 million) and some millions of relationship. In this case...what are
> performances with the built-in algorithms Dijkstra and/or A* when i want
> the shortest path (or all paths) between two points located at the end of
> the graph?
>
> Thank you
> Angelo
>
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