jgrapht-users — JGraphT user list.

[jgrapht-users] JGraphT backport

[John V. S. <js...@gm...>]

The JGraphT development version (0.7.0alpha) in CVS requires JDK 1.5 to 
build, but I've just checked in backport support to allow it to run on 
JRE 1.4.  To use it, install Retroweaver (and JRE 1.4), then create a 
file named customBuild.properties in the same directory as build.xml and 
add these two lines:

retroweaver.dir=/path/to/full/distribution/of/retroweaver
retro.jre.dir=/path/to/jre1.4

Then run ant.  The "all" target will perform a normal build/test/jar 
sequence, and then run the backport (overwriting the class files in 
place with their retrowoven versions).  Then it will re-run all tests 
against JRE 1.4 to make sure that no dependencies on JRE 1.5 have crept 
in.  Finally, it will create an extra jar with the retrowoven classes as 
part of the distribution.

If you have comments on this process, please let me know.

JVS

Re: [jgrapht-users] Array of neighbours

[John V. S. <js...@gm...>]

GraphHelper has methods neighborListOf, predecessorListOf and
successorListOf.

JVS

> Julien Thomas de Boer wrote:
> 
>> Hi everyone,
>> Does someone know how to get an array with neighbour nodes of a given
>> vertice ? I thought it was possible but i didnt manage to find how in
>> the Javadoc. Thanks for your help.
>>  
> 
> 

[jgrapht-users] Array of neighbours

[Julien T. de B. <jul...@ep...>]

Hi everyone,
Does someone know how to get an array with neighbour nodes of a given
vertice ? I thought it was possible but i didnt manage to find how in
the Javadoc. Thanks for your help.
 
-- 
Sincerely,

Julien THOMAS DE BOER
Swiss Federal Institute of Technology of Lausanne (EPFL)

[jgrapht-users] JGraphT role changes

[Barak N. <bar...@us...>]

Dear JGraphT community,

I started JGraphT because I needed a graph library and no existing =
library
suited my needs.  I needed high performance graphs with low memory
consumption, and wanted the vertices to be of ANY type (annoyingly, many
libraries require the vertices to implement some Vertex interface). =20

At some point I realized that others might find JGraphT useful, so I =
made
the project open-source.  People indeed used it, reported bugs, =
requested
features, and contributed code.  Some even joined in and the whole thing
became a lot more fun than I anticipated!  The quality of the library =
has
improved continuously thanks to the received contributions and criticism =
--
it was a very convincing example how open source development produces =
better
software!

In the last year I became less and less available to admin JGraphT.  =
This
situation is unlikely to change in the near future, so we are making a =
role
change.  John V. Sichi, who has been a JGraphT developer and a co-admin =
for
a long time, is now taking the lead.  John is now the chief maintainer =
of
JGraphT, and although I'm staying involved, you should address project
issues to John.

JGraphT is going forward!  Version 0.6.0 was recently released and =
version
0.7.0 that will support Generics is now cooking...  The move to Java 5.0 =
is
thanks to the contribution of Christian Hammer.  If you can't wait for =
the
new candies, you might want to lend a hand and help making 0.7.0 ready
sooner...
 =20
Thanks to everyone for making it so much fun, and special thanks to John =
V.
Sichi who volunteered to lead JGraphT onwards.

Yours,
Barak Naveh

[jgrapht-users] JDK 1.5 support under development in CVS

[John V. S. <js...@gm...>]

Christian Hammer has submitted changes to the core JGraphT data 
structures to take advantage of JDK 1.5 language features, in particular 
generics.  This will become the basis for JGraphT 0.7.0.

If you check out the latest from CVS, you'll need to start using JDK 1.5 
to compile.  Backwards compatibility support for running on JVM 1.4 is 
planned via the RetroWeaver project.

If you'd like to help out with the next release, there are a number of 
subpackages of org._3pq.jgrapht (e.g. generate, ext) which should be 
updated with support for generics, as well as the entire testsrc 
directory (the goal should be to build without any -Xlint:unchecked 
warnings).

JVS

[jgrapht-users] JGraphT 0.6.0

[John V. S. <js...@gm...>]

At long last, JGraphT version 0.6.0 has been released and is now 
available to download from http://jgrapht.sf.net. Please address any 
problems with the release to me.

Enjoy,
JVS

Re: [jgrapht-users] Specifying edges' appearance

[<Tom...@lo...>]

Dear Kyle et al,

I've solved my little problem and I'm posting the resulting code here.
I'm afraid that the code it's really kludgy, but as I've seen that this 
is a common problem, I'm pasting it hoping that it will be useful to 
someone.

// first we create an add the edge
ObjectHolderDirectedEdge edge = new ObjectHolderDirectedEdge(firstNode, 
secondNode, anObject);
graph.addEdge(edge);  // graph is a JGraphT ListenableGraph

// then we modify it's appearance
Map nested = new Hashtable();
Map attributeMap = new Hashtable();
DefaultGraphCell edgeCell = jgraphAdapter.getEdgeCell(edge);  // jgraph 
is, obviously a JGraph object.
                                                              // 
jgraphAdapter is a JGraphModelAdapter

GraphConstants.setLineColor(attributeMap, Color.BLUE);
GraphConstants.setLineEnd(attributeMap, GraphConstants.ARROW_TECHNICAL);
GraphConstants.setEditable(attributeMap, false);

nested.put(edgeCell, attributeMap);
jgraph.getGraphLayoutCache().edit(nested, null, null, null); 

hth.
best to all,
 tom.

Kyle Lahnakoski wrote:

> Can you cut and paste the toString() code?  I would like to know what 
> you mean by cusomizing the look.  Your original post seemed to 
> indicate you wanted to change the graphical look (somehow interfacing 
> with jgraph to change vertex and edge graphics).  But your recent post 
> indicates you just wanted to change the text.
>
> Which was it?
>
> Thanks.
>
>
> Tomás Laurenzo wrote:
>
>> Dear all,
>>
>>
>>
>> I've managed to overcome my little problem by creating a new kind of 
>> JGraphT Edge (ObjectHolderDirectedEdge extends DirectedEdge), and using
>> it for my project.
>>
>> By overriding it's toString() method I got the desired customization 
>> (it also holds a value, hence it's name).
>>
>> best,
>>  tom.
>>
>>
>>
>> -------------------------------------------------------
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>> from IBM. Find simple to follow Roadmaps, straightforward articles,
>> informative Webcasts and more! Get everything you need to get up to
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>> _______________________________________________
>> jgrapht-users mailing list
>> jgr...@li...
>> https://lists.sourceforge.net/lists/listinfo/jgrapht-users
>>
>
>

Re: [jgrapht-users] Specifying edges' appearance

[<Tom...@lo...>]

Dear Kyle,

I at first wanted to customize both the graphical appearance and the text.
As you say, by overriding the toString() method I only can change it's 
text. Sadly, the graphical customization remains unsolved.

best,
tom.

Kyle Lahnakoski wrote:

> Can you cut and paste the toString() code?  I would like to know what 
> you mean by cusomizing the look.  Your original post seemed to 
> indicate you wanted to change the graphical look (somehow interfacing 
> with jgraph to change vertex and edge graphics).  But your recent post 
> indicates you just wanted to change the text.
>
> Which was it?
>
> Thanks.
>
>
> Tomás Laurenzo wrote:
>
>> Dear all,
>>
>>
>>
>> I've managed to overcome my little problem by creating a new kind of 
>> JGraphT Edge (ObjectHolderDirectedEdge extends DirectedEdge), and using
>> it for my project.
>>
>> By overriding it's toString() method I got the desired customization 
>> (it also holds a value, hence it's name).
>>
>> best,
>>  tom.
>>
>>
>>
>> -------------------------------------------------------
>> SF.Net email is sponsored by: Discover Easy Linux Migration Strategies
>> from IBM. Find simple to follow Roadmaps, straightforward articles,
>> informative Webcasts and more! Get everything you need to get up to
>> speed, fast. http://ads.osdn.com/?ad_id=7477&alloc_id=16492&op=click
>> _______________________________________________
>> jgrapht-users mailing list
>> jgr...@li...
>> https://lists.sourceforge.net/lists/listinfo/jgrapht-users
>>
>
>

Re: [jgrapht-users] Edge: variable weight

[Kyle L. <ky...@ar...>]

Your second sentence was unclear, so I will ignore it, dispite it 
sounding important.

I assume you have a set of objects (or equivalent) that can provide the 
required weights.

You can have those objects implement the Edge interface, and then use 
them in your graph instead of the DirectedWeightedEdge.

Alternativly, you could make one DirectedWeightedEdge for each object, 
using the object  weights in the constructor.


Good luck



Alessandro wrote:

> Hi jgraphtrs,
>
>
> I use the dijkstra alghoritm (in 
> org._3pq.jgrapht.alg.DijkstraShortestPath).. it use getWeight() method 
> in edge (DirectedEdge).
> Well! I wish a variable weight for each edge (depend on a parameter; 
> this parameter is present in the object which call 
> DijkstraShortestPath method).
>
> Some suggestion?
>
> Thank you very much!
> Bye bye,
>     Alessandro
>
>
>
>
> -------------------------------------------------------
> SF.Net email is sponsored by: Discover Easy Linux Migration Strategies
> from IBM. Find simple to follow Roadmaps, straightforward articles,
> informative Webcasts and more! Get everything you need to get up to
> speed, fast. http://ads.osdn.com/?ad_id=7477&alloc_id=16492&op=click
> _______________________________________________
> jgrapht-users mailing list
> jgr...@li...
> https://lists.sourceforge.net/lists/listinfo/jgrapht-users
>


-- 
----------------------------------------------------------------------
Kyle Lahnakoski                                       ky...@ar...
(416) 892-7784                                    Arcavia Software Ltd

Re: [jgrapht-users] Specifying edges' appearance

[Kyle L. <ky...@ar...>]

Can you cut and paste the toString() code?  I would like to know what 
you mean by cusomizing the look.  Your original post seemed to indicate 
you wanted to change the graphical look (somehow interfacing with jgraph 
to change vertex and edge graphics).  But your recent post indicates you 
just wanted to change the text.

Which was it?

Thanks.


Tomás Laurenzo wrote:

> Dear all,
>
>
>
> I've managed to overcome my little problem by creating a new kind of 
> JGraphT Edge (ObjectHolderDirectedEdge extends DirectedEdge), and using
> it for my project.
>
> By overriding it's toString() method I got the desired customization 
> (it also holds a value, hence it's name).
>
> best,
>  tom.
>
>
>
> -------------------------------------------------------
> SF.Net email is sponsored by: Discover Easy Linux Migration Strategies
> from IBM. Find simple to follow Roadmaps, straightforward articles,
> informative Webcasts and more! Get everything you need to get up to
> speed, fast. http://ads.osdn.com/?ad_id=7477&alloc_id=16492&op=click
> _______________________________________________
> jgrapht-users mailing list
> jgr...@li...
> https://lists.sourceforge.net/lists/listinfo/jgrapht-users
>


-- 
----------------------------------------------------------------------
Kyle Lahnakoski                                       ky...@ar...
(416) 892-7784                                    Arcavia Software Ltd

Re: [jgrapht-users] Dijktra shorthest problem with subgraphs

[Kyle L. <ky...@ar...>]

I looked at the code

The Subgraph class has a bug (or more).  TheDijkstraShortestPath will 
eventually use Subgraph.outgoingEdgesOf().  Here is the code:

    public List outgoingEdgesOf( Object vertex ) {
        return ( (DirectedGraph) *m_base* ).outgoingEdgesOf( vertex );
    }

Notice that the m_base is the original supergraph, not some subset.


Julien Thomas de Boer wrote:

>Hello everyone,
>Does someone know why this problem occurs :
>Given a ListenableDirectedWeighted graph g. I build the subgraph s from
>g. Imagine now I want to check the path between two nodes, A and B
>(connected in g but not in s). When I use :
>List chemin = DijkstraShortestPath.findPathBetween(s,"A","B");
>In chemin, it returns the path in g but not in s.
>How is it possible ? Do you know how to solve this problem ? Thanks a
>lot for your attention.
>
>
>  
>


-- 
----------------------------------------------------------------------
Kyle Lahnakoski                                       ky...@ar...
(416) 892-7784                                    Arcavia Software Ltd

[jgrapht-users] Dijktra shorthest problem with subgraphs

[Julien T. de B. <jul...@ep...>]

Hello everyone,
Does someone know why this problem occurs :
Given a ListenableDirectedWeighted graph g. I build the subgraph s from
g. Imagine now I want to check the path between two nodes, A and B
(connected in g but not in s). When I use :
List chemin = DijkstraShortestPath.findPathBetween(s,"A","B");
In chemin, it returns the path in g but not in s.
How is it possible ? Do you know how to solve this problem ? Thanks a
lot for your attention.


-- 
Sincerely,

Julien THOMAS DE BOER
Swiss Federal Institute of Technology of Lausanne (EPFL)

[jgrapht-users] Edge: variable weight

[Alessandro <al...@in...>]

Hi jgraphtrs,


I use the dijkstra alghoritm (in 
org._3pq.jgrapht.alg.DijkstraShortestPath).. it use getWeight() method 
in edge (DirectedEdge).
Well! I wish a variable weight for each edge (depend on a parameter; 
this parameter is present in the object which call DijkstraShortestPath 
method).

Some suggestion?

Thank you very much!
Bye bye,
	Alessandro

RE: [jgrapht-users] Specifying edges' appearance

[<Tom...@lo...>]

Dear all,



I've managed to overcome my little problem by creating a new kind of 
JGraphT Edge (ObjectHolderDirectedEdge extends DirectedEdge), and using
it for my project.

By overriding it's toString() method I got the desired customization (it 
also holds a value, hence it's name).

best,
  tom.

[jgrapht-users] Specifying edges' appearance

[<Tom...@lo...>]

Dear all,

Is it possible to specify the appearance of an edge via JGraphT?
I've noticed that this question has been asked a few times but remains 
unanswered. Could anyone please post an answer?

(a little bit of context: I have my project almost finished but I do 
need some kind of graphical customization and backtracking to a version 
w/o JgraphT would imply a huge effort).

Thank you very much,
tom.

[jgrapht-users] weighted graphs

[Kenneth S. <ke...@Vi...>]

Hi - would someone be kind enough to get me started on 
weighted graphs? 

Maybe a simple example?

Any help would be greatly appreciated! 

-- Ken

[jgrapht-users] Maximum size for a Jgrapht graph

[Julien T. de B. <jul...@ep...>]

Hello everybody,
Does someone know what it is the maximum number of nodes a Jgrapht graph 
can support ?
Thanks for this info.

-- 
Sincerely,

Julien THOMAS DE BOER
Laboratory of Computer Communication and Application (LCA)
Swiss Federal Institute of Technology Lausanne (EPFL)

[jgrapht-users] Where are the graph algorithms?

[Kyle L. <ky...@ar...>]

I am brand new to JGraphT.  I like the fact it integrates with JGraph 
easily; I never had the time to use JGraph becasue of it's API learning 
curve.

For my main point.  Where are the graph algorithms?  From the main page 
it says:

    /JGraphT is a free Java graph library that provides mathematical
    graph-theory objects and *algorithms*
    /

I have found DijkstraShortestPath(), but that is it.

Thanks

-- 
----------------------------------------------------------------------
Kyle Lahnakoski                                       ky...@ar...
(416) 892-7784                                    Arcavia Software Ltd

[jgrapht-users] HOW TO ADD IMAGE IN VERTEX

[Arun K. <aru...@gm...>]

Hi all,
Currently am using JGraphT but i need to add ImageIcon in the Vertex ,
please tell me how to do it.

Regards
Arunkumar.H.G

--=20
Developer to Developer Connection
http://www.arunzone.com
INSPIRATION HAS MANY FACES

Re: [jgrapht-users] OutofMemory Error

[Michael B. <beh...@in...>]

=2D----BEGIN PGP SIGNED MESSAGE-----
Hash: SHA1

Am Mittwoch, 9. M=E4rz 2005 14:47 schrieb Balaji Iyengar:
> Hello,
>
> I am using Jgrapht to study the properties of some garbage collection
> algorithms and I am running out of memory (Java.lang.outofmemory
> error), has anybody faced this before while using Jgrapht? In my case
> the graph has about 3-4 million objects on an average, are there ways
> to get around this?

Try java -Xmx500m or whatever amount of memory you want to spent
(and you physically have). Try java -X for an explanation of the option.

Michael

=2D --=20
Michael Behrisch (Tel. +49 30 2093-3123)
HU Berlin, Institut fuer Informatik, Arbeitsgruppe Algorithmen
http://www.informatik.hu-berlin.de/~behrisch/
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Version: GnuPG v1.2.4 (GNU/Linux)

iD8DBQFCMAHjZDyR4hR8HnQRAreUAKC93i+ZhIQLxeeGLUYPAYbrNpUp8ACfXfsj
OvrvKbEbTNZMcYuUCkvL+hU=3D
=3DJOf8
=2D----END PGP SIGNATURE-----

[jgrapht-users] OutofMemory Error

[Balaji I. <bri...@gm...>]

Hello,

I am using Jgrapht to study the properties of some garbage collection
algorithms and I am running out of memory (Java.lang.outofmemory
error), has anybody faced this before while using Jgrapht? In my case
the graph has about 3-4 million objects on an average, are there ways
to get around this?

thanks
-balaji

Re: [jgrapht-users] graph object instantiation.

[Balaji I. <bri...@gm...>]

i fixed it, I was doing this:
DefaultDirectedGraph g_graph = new DefaultDirectedGraph();
in the constructor which was creating a new object rather than
instantiating the class member.

thanks
-balaji


On Tue, 8 Mar 2005 09:33:04 -0500, Balaji Iyengar <bri...@gm...> wrote:
> I was just typing some sort of a psuedo code. I got those right in my
> program. It looks like the reference returned by the
> DefaultDirectedGraph constructor is alive only in the body of the
> method it is in. So if you have this:
> 
> protected final void sample_method(){
> DefaultDirectedGraph g_graph = new DefaultDirectedGraph();
>  Integer tp_obj = new Integer(2);
>  g_graph.addVertex(tp_obj);
> }
> 
> then it works fine without a nullpointer exception.
> 
> thanks
> -balaji
> 
> On Tue, 8 Mar 2005 09:07:35 -0500, Bergeron Guyard, Alexandre
> <Ale...@dr...> wrote:
> > Well,
> >
> > From the little I see, I have a few ideas:
> >
> > 1) In your class you declare a method addNode(), but you later call
> > addVertex()....
> >
> > 2) You instanciate a SampleGraph under the name tmp-graph-obj, but use the
> > name tmp-obj to call the addNode()/addVertex() method later on...
> >
> > Hope this helps.
> >
> > Alex
> >
> > -----Original Message-----
> > From: Balaji Iyengar [mailto:bri...@gm...]
> > Sent: March 8, 2005 8:19 AM
> > To: jgr...@li...
> > Subject: [jgrapht-users] graph object instantiation.
> >
> > Hello,
> >
> > I have a DefaultDirectedGraph object as a private member of a class,
> > which i instantiate in the constructor of the class. I then use call
> > the addVertex function later from other files in my code structure.
> > This is how my class looks like:
> >
> > class SampleGraph {
> > private DefaultDirectedGraph g_graph;
> > // other members
> >
> > // constructor
> > SampleGraph(){
> > DefaultDirectedGraph g_graph = new DefaultDirectedGraph();
> > }
> >
> > // wrapper method
> > protected final boolean addNode(Object gnode){
> > return g_graph.addVertex(gnode);
> > }
> > }
> >
> > elsewhere in the code i do:
> >
> > SampleGraph tmp-graph-obj = new SampleGraph ();
> > tmp-obj.addVertex(tmp-node);
> >
> > which should add the tmp-node to the g_graph member of tmp-graph-obj,
> > is this the right way of doing this. I get a null pointer exception
> > here and i cant figure what i am doing wrong here.
> > Any help would be very much appreciated.
> >
> > thanks
> >
> > -------------------------------------------------------
> > SF email is sponsored by - The IT Product Guide
> > Read honest & candid reviews on hundreds of IT Products from real users.
> > Discover which products truly live up to the hype. Start reading now.
> > http://ads.osdn.com/?ad_id=6595&alloc_id=14396&op=click
> > _______________________________________________
> > jgrapht-users mailing list
> > jgr...@li...
> > https://lists.sourceforge.net/lists/listinfo/jgrapht-users
> >
>

Re: [jgrapht-users] graph object instantiation.

[Balaji I. <bri...@gm...>]

I was just typing some sort of a psuedo code. I got those right in my
program. It looks like the reference returned by the
DefaultDirectedGraph constructor is alive only in the body of the
method it is in. So if you have this:

protected final void sample_method(){
DefaultDirectedGraph g_graph = new DefaultDirectedGraph();
 Integer tp_obj = new Integer(2);
 g_graph.addVertex(tp_obj);
}

then it works fine without a nullpointer exception.

thanks
-balaji

On Tue, 8 Mar 2005 09:07:35 -0500, Bergeron Guyard, Alexandre
<Ale...@dr...> wrote:
> Well,
> 
> From the little I see, I have a few ideas:
> 
> 1) In your class you declare a method addNode(), but you later call
> addVertex()....
> 
> 2) You instanciate a SampleGraph under the name tmp-graph-obj, but use the
> name tmp-obj to call the addNode()/addVertex() method later on...
> 
> Hope this helps.
> 
> Alex
> 
> -----Original Message-----
> From: Balaji Iyengar [mailto:bri...@gm...]
> Sent: March 8, 2005 8:19 AM
> To: jgr...@li...
> Subject: [jgrapht-users] graph object instantiation.
> 
> Hello,
> 
> I have a DefaultDirectedGraph object as a private member of a class,
> which i instantiate in the constructor of the class. I then use call
> the addVertex function later from other files in my code structure.
> This is how my class looks like:
> 
> class SampleGraph {
> private DefaultDirectedGraph g_graph;
> // other members
> 
> // constructor
> SampleGraph(){
> DefaultDirectedGraph g_graph = new DefaultDirectedGraph();
> }
> 
> // wrapper method
> protected final boolean addNode(Object gnode){
> return g_graph.addVertex(gnode);
> }
> }
> 
> elsewhere in the code i do:
> 
> SampleGraph tmp-graph-obj = new SampleGraph ();
> tmp-obj.addVertex(tmp-node);
> 
> which should add the tmp-node to the g_graph member of tmp-graph-obj,
> is this the right way of doing this. I get a null pointer exception
> here and i cant figure what i am doing wrong here.
> Any help would be very much appreciated.
> 
> thanks
> 
> -------------------------------------------------------
> SF email is sponsored by - The IT Product Guide
> Read honest & candid reviews on hundreds of IT Products from real users.
> Discover which products truly live up to the hype. Start reading now.
> http://ads.osdn.com/?ad_id=6595&alloc_id=14396&op=click
> _______________________________________________
> jgrapht-users mailing list
> jgr...@li...
> https://lists.sourceforge.net/lists/listinfo/jgrapht-users
>

[jgrapht-users] graph object instantiation.

[Balaji I. <bri...@gm...>]

Hello, 
 
I have a DefaultDirectedGraph object as a private member of a class,
which i instantiate in the constructor of the class. I then use call
the addVertex function later from other files in my code structure.
This is how my class looks like:
 
class SampleGraph { 
private DefaultDirectedGraph g_graph; 
// other members 
 
// constructor 
SampleGraph(){  
DefaultDirectedGraph g_graph = new DefaultDirectedGraph(); 
} 
 
// wrapper method 
protected final boolean addNode(Object gnode){ 
return g_graph.addVertex(gnode); 
}  
} 
 
elsewhere in the code i do: 
 
SampleGraph tmp-graph-obj = new SampleGraph (); 
tmp-obj.addVertex(tmp-node); 
 
which should add the tmp-node to the g_graph member of tmp-graph-obj,
is this the right way of doing this. I get a null pointer exception
here and i cant figure what i am doing wrong here.
Any help would be very much appreciated. 
 
thanks

[jgrapht-users] Is Jgrapht what I need ?

[D. S. D. <dav...@us...>]

I was looking to use the JGrapht classes to
build programs to display and edit data plots using x-y
coordinates.

Is Jgrapht what I can use ? Are there any postings of examples
like this to get me started ?