Hi Bryce,
Nice to see you back.
The OSM data model in Neo4j-Spatial, created by the OSMImporter, is designed
to mimic the complete contents of the XML files provided for OSM. As it is,
this is not ideal for routing because it traces the complete set of nodes
for the ways, while for routing you
Hi,
Recently someone asked a question on StackOverflow, if Neo4j Spatial was
capable of one of the Oracle geoprocessing funtions, SDO_LRS.LOCATE_PT
specifically. Since this is related to the ongoing GSoC projects for Neo4j
Spatial, I thought I would do a quick investigation. What I found was that
Hi Mirco,
Sounds like progress. Some suggestions:
- I do not think you need to change the code for neo4j and udig, but only
for neo4j-spatial and udig-community/neo4j. It is OK to make clones of those
so you have the code for review, but they are quite core, and you should not
need
Hi,
The bounding boxes are used by the RTree index, which is a typical way to
index spatial data. For Point data, the lat/long and the bounding box are
the same thing, but for other shapes (streets/LineString and Polygons), the
bounding box is quite different to the actual geometry (which is not
of
a set of points, rather than individual points. So the query is, find the
nodes where the given point falls inside their bounding boxes. Can I do
this
with REST?
Thanks!
On Tue, Jun 7, 2011 at 11:34 AM, Craig Taverner cr...@amanzi.com wrote:
Hi,
The bounding boxes are used by the RTree
://www.neo4j.org - Your high performance graph database.
http://startupbootcamp.org/- Öresund - Innovation happens HERE.
http://www.thoughtmade.com - Scandinavia's coolest Bring-a-Thing party.
On Thu, Jun 2, 2011 at 2:13 PM, Craig Taverner cr...@amanzi.com wrote:
Hi,
Recently
I suggest you code review them first. Especially since there are API
changes.
On Tue, Jun 7, 2011 at 10:11 AM, Peter Neubauer
peter.neuba...@neotechnology.com wrote:
Very nice Andreas!
You consider it safe to pull these changes into the main repo?
Cheers,
/peter neubauer
GTalk:
this
with REST?
Thanks!
On Tue, Jun 7, 2011 at 11:34 AM, Craig Taverner cr...@amanzi.com
wrote:
Hi,
The bounding boxes are used by the RTree index, which is a typical
way
to
index spatial data. For Point data, the lat/long and the bounding box
are
the same thing
Hi Saikat,
Yes, your explanation was clear, but I was busy with other work and failed
to repond - my bad ;-)
Anyway, your idea is nice. And I can think of a few ways to model this in
the graph, but at the end of the day the most important thing to decide
first is what queries are you going to
Think of your domain model graph as a kind of index. Traversing that should
generally be faster than a generic index like lucene. Of course some things
do not graph well, and you should use lucene for those. But if you can find
something with a graph traversal, that is likely the way to go.
Also
This is great news.
Now I'm really curious about the next step, and that is allowing indexes
other than lucene. For example, the RTree index in neo4j-spatial was never
possible to wrap behind the normal index API, because that was designed only
for properties of nodes (and relationships), but the
Could this also be related to the possibility that in order to determine
relationship type and direction, the relationships need to be loaded from
disk? If so, then having a large number of relationships on the same node
would decrease performance, if the number was large enough to affect the
disk
Another common thing to do in this case is create a node for the purchase
action. This node would be related to the purchaser (user), item (pen) and
shop, and would contain data appropriate to the purchase (date/time, price,
etc).
Then traverse from the shop or the pen to all purchase actions
I understood that on windows the memory mapped sizes needed to be included
in the heap, since they are not allocated outside the heap as they are on
linux/mac. So in this case he needs a larger heap (and make sure the memory
mapped files are much smaller than the heap). The relevant part of the
performance graph
database.
http://startupbootcamp.org/- Öresund - Innovation happens HERE.
http://www.thoughtmade.com - Scandinavia's coolest Bring-a-Thing party.
On Tue, Jun 14, 2011 at 5:49 PM, Craig Taverner cr...@amanzi.com
wrote:
This is great news.
Now I'm really curious about
Hi Nolan,
I think I can answer a few of your questions. Firstly, some background. The
graph model of the OSM data is based largely on the XML formated OSM
documents, and there you will find 'nodes', 'ways', 'relations' and 'tags'
each as their own xml-tag, and as a consequence each will also have
Hi Christopher,
Thanks for your interest in neo4j and neo4j-spatial. I will answer your
questions and comments inline.
I am working for the largest German speaking travel and holiday portal.
Currently we are using a relatively simple MySQL based spatial distance
functionality. We plan to
I heard that Peter Neubauer made a port of neo4j to android a few years ago,
but that nothing has been done since and no version since then would work.
So my understanding is that it does not work on android, but that it is
possible to make it work (with some work ;-).
Peter is away, but I expect
that Android exposes.
-Original Message-
From: user-boun...@lists.neo4j.org [mailto:user-boun...@lists.neo4j.org]
On Behalf Of Craig Taverner
Sent: Friday, June 24, 2011 8:37 AM
To: Neo4j user discussions
Subject: Re: [Neo4j] Neo4j -- Can it be embedded in Android?
I heard
Hi,
Has anyone noticed a slowdown of imports into neo4j with recent snapshots?
Neo4j-spatial importing OSM data (which uses lucene to find matching nodes
for ways) is suddenly running much slower than usual on non-batch imports.
For most of my medium sized test cases, I normally have surprisingly
if I can find some culprit for this.
But again, a little more information would be useful, as always.
2011/6/26 Craig Taverner cr...@amanzi.com
Hi,
Has anyone noticed a slowdown of imports into neo4j with recent
snapshots?
Neo4j-spatial importing OSM data (which uses lucene to find
back to 5000
increased the node creation rate to nearly 1 (over 100 times faster).
That is a serious improvement.
Sorry again for wasting space on the list. I'm glad this was a user error,
though, not a neo4j issue :-)
Regards, Craig
On Mon, Jun 27, 2011 at 12:54 AM, Craig Taverner cr
Hi,
I can comment on the spatial side. The
neo4j-spatialhttps://github.com/neo4j/neo4j-spatiallibrary provides
some tools for doing spatial analysis on your data. I do
not know exactly what you plan to do, but since you mention user and place
locations, I guess you are likely to be asking the
The RTree in principle should be generalizable, but the current
implementation in neo4j-spatial does make a few assumptions specific to
spatial data, and makes use of spatial envelopes for the tree node bounding
boxes. It is also specific to 2D. We could make a few improvements first,
like
I have previously used two solutions to deal with multiple types in btrees:
- My first index in 2009 was a btree-like n-dim index using generics to
support int[], long[], float[] and double[] (no strings). I used this for
TimeLine (long[1]) and Location (double[2]). The knowledge about
It is technically possible, but it is a somewhat specialized index, not a
normal BTree, so I think you would want both (mine and a classic btree). My
index performs better for certain data patterns, is best with semi-ordered
data and moderately even distributions (since it has no rebalancing), and
I think moving the RTree to the generic collections would not be too hard. I
saw Saikat showed interested in doing this himself.
Saikat, contact me off-list for further details on what I think could be
done to make this port.
On Wed, Jun 29, 2011 at 9:52 PM, Niels Hoogeveen
This topics has come up before, and the domain level solutions are usually
very similar, like Norbert's category/proxy nodes (to group by
type/direction) and Niels' TimeLineIndex (BTree). I wonder whether we can
build a generic user-level solution that can also be wrapped to appear as an
internal
Hi Kriti,
I can comment on a few things, especially neo4j-spatial:
- Neo4j is certainly good for social networks, and people have used it
for that, but I personally do not have experience with that so I will not
comment further (others can chip in where necessary).
- Neo4j-Spatial is
In the amanzi-index I link all indexed nodes into the index tree, so
traversals are straight up the tree. Of course this also means that there
are at least as many relationships as indexed nodes.
I was reviewing Michaels code for the relationship expander, and think that
is a great idea,
Hi Andreas,
Sounds like good progress over all. It is only a week to the mid-terms, so
it would be good to do a general code overview and see if this can be
integrated with trunk. Shall we plan for a review and test integration in
the middle of next week?
Regards, Craig
On Sat, Jul 2, 2011 at
As far as I know there is no internal support for transparent traversals
across shards. Generally people are doing that in the application layer.
However, I think there might be a middle ground of sorts. I we modify the
relationship expander, I could imagine that relationships that are between
Hi Boris,
You do not need to read the property yourself from the node, rather use the
GeometryEncoder for this, it converts from the internal spatial storage to
the Geometry class, which you can work with. If you call geom.toString() you
will get a nice printable version (in WKT). Using the
!
On Wed, Jun 8, 2011 at 4:58 PM, Craig Taverner cr...@amanzi.com wrote:
OK. I understand much better what you want now.
Your person nodes are not geographic objects, they are persons that can
be
at many positions and indeed move around. However, the 'path' that they
take
is a geographic
, Craig Taverner cr...@amanzi.com
wrote:
Hi Boris,
Ah! You are using the REST API. That changes a lot, since Neo4j Spatial
is
only recently exposed in REST and we do not expose most of the
capabilities
I have discussed in this thread, or indeed in my other answer today.
I did
Hi,
Recent builds of Neo4j-Spatial no longer like Peters new bounding box query.
Peter is on vacation, and I am not familiar with the code (nor cypher), so I
thought I would just dump the error message here for now in case someone can
give me a quick pointer.
The line of code is:
Query query =
can't find the code on github.
Thanks!
On Sat, Jul 2, 2011 at 6:00 PM, Craig Taverner cr...@amanzi.com wrote:
As I understand it, Andreas is working on the much more complex problem
of
updating OSM geometries. That is more complex because it involves
restructuring the connected graph
Another option is to run the main method of OSMImport class, which expects
command line arguments for database location and OSM file, and will simply
import a file once. This is not tested often, so there is a risk things have
changed, but it is worth a try.
Another, even easier, option in my
isn't with the
DB.
Thanks,
Robin Cura
2011/7/9 Craig Taverner cr...@amanzi.com
Another option is to run the main method of OSMImport class, which
expects
command line arguments for database location and OSM file, and will
simply
import a file once. This is not tested often, so there is a risk
I'm not sure it's such a good idea to call tx.success() on every iteration
of the loop. I suggest call it only in the commit, and after the loop (ie.
move it two lines down).
Also I think a commit size of 50k it a little large. You're probably not
going to see much improvement past 10k. In fact I
Interesting that if you look at the github 'blame' for that file (see
https://github.com/neo4j/neo4j-spatial/blame/master/src/main/java/org/neo4j/gis/spatial/SpatialTopologyUtils.java),
you find that all the findClosestEdges methods where added in October 2010.
So if Nolan has a version older than
Actually we do allow multiple geometry types in the same layer, but some
actions, like export to shapely, will fail. We even test for this in
TestDynamicLayers.
You can use the gtype if you want, but it is specific to some
GeometryEncoders, and might change in future releases. It would be better
at 10:50 PM, Craig Taverner cr...@amanzi.com wrote:
Actually we do allow multiple geometry types in the same layer, but some
actions, like export to shapely, will fail. We even test for this in
TestDynamicLayers.
You can use the gtype if you want, but it is specific to some
Or if you want a command line import, try the ruby gem 'neo4j-spatial.rb'.
Once installed you can type:
osm_import file.shp
On Aug 13, 2011 10:33 AM, Andreas Wilhelm a...@kabelbw.de wrote:
Hi,
with the pgsql2shp tool you can dump your postgis db in a shapefile and
you should be able to import
I can elaborate a little on what Peter says. The DynamicLayer support is
indeed the only way to do what you want right now, but I think it is
actually quite a good fit for your use case. When defining a dynamic layer
you are actually just defining a 'returnable evaluator', which will be
applied to
I think Daniels questions are very relevant, but not just to OSM. Any large
graph (of which OSM is simply a good example) will be affected by
fragmentation, and that can affect performance. I recently was hit by
performance of GIS queries (not OSM) related to fragmentation of the index
tree. I
Hi all,
I am certainly behind on my emails, but I did just answer a related question
about OSM and fragmentation, and I think that might have answered some of
Daniels questions.
But I can say a little more about OSM and Neo4j here, specifically about the
issue of joins in postgres. Let me start
Sorry for such a late response, I missed this mail.
I must first point out that it seems you are trying to use Neo4j-Spatial in
the standalone server version of Neo4j. That is possible, but not well
supported. We have only exposed a few of the functions in the server, and do
not test it
Hi,
Sorry for a late contribution to this discussion. I will try make a few
comments to cover the various mails above.
Firstly, the neo4j-spatial.rb GEM at version 0.0.8 on RubyGems works with
Neo4j-Spatial 0.6, which does include the non-batch inserter code, so in
principle should work for you.
I did some initial work on incremental imports back in 2010, but stopped
due to some complications:
- We needed to mix lucene reads and writes during the import (read to
check if the node already exists, so we don't import twice) and this
performs very badly in the batch inserter. We
There are two approaches I can think of:
- use a better index for mapping ids. Lucent is too slow. Memory hashtables
are memory bound.Peter has been investigating alternative dbs like bdb. I
tried, but did not finish a hashmap of cached arrays, and Chris wrote his
big data import project on
What is the sort order? Date of first commit, number of lines, commits,
packages?
On Nov 21, 2011 2:35 PM, Peter Neubauer peter.neuba...@neotechnology.com
wrote:
Everyone,
have started to put in some random people in, see
http://docs.neo4j.org/chunked/snapshot/contributors.html .
Any ideas
There was only a method ending in 'WithCheck', or something like that,
lying unused in the code from last year. Nothing more than that. Except for
thinking about it, which is why I wrote the previous mail.
On Dec 2, 2011 12:50 PM, Peter Neubauer pe...@neubauer.se wrote:
Not sure,
Craig, do you
Of course the graph can be used for processing event data, and whether
that works for your case or not depends. But we have used it for this,
and I can discuss a few points.
The event stream is obviously just a linear chain and can be modeled
as such in the graph (eg. with NEXT relationships
We do indeed have twice the node count (and twice the relationship
count). This is a necessary side effect of the fact that an OSM node
can participate in more than one way (at intersections as well as
shared edges of polygons, etc.). In addition, with shared edges the
direction can be reversed
I definitely second this suggestion. We have recently being working on a
binary store for dense data we would like to access as if they were
properties of nodes. Right now we have properties that are references to
files on disk, and then handle the binary ourselves, but this does not
benefit from
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