jgrapht-users — JGraphT user list.

[jgrapht-users] DirectedNeighborIndex

[Claudio M. <cla...@gm...>]

Hi,

I'm implementing a few algorithms that make extensive use of local
neighborhoods of Vertexes. Therefore I'd like to use
DirectedNeighborIndex class to speed up the computation. At the moment
I've extended SimpleDirectedWeightedGraph and added the methods
outgoingVertexesOf(V) and incomingVertexesOf(V), both cycling over the
results of outgoingEdgesOf() and incomingEdgesOf(). What I'm trying to
understand is re-implementing these outgoingVertexesOf() and
incomingVertexesOf() with calls to  predecessorOf() and successorOf()
of DirectedNeighborhorIndex is the smartest way to optimize my code.
My second question, connected to the first one, is if it's possible,
if it's not already been used, to ask the graph to cache the calls
internally for some computation.

TIA

/CM

-- 
    Claudio Martella
    cla...@gm...

Re: [jgrapht-users] Average path length

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

Claudio Martella wrote:
> yes, that's what i want. i guess i should first transform my graph
> into adjacent matrix representation in order to do so. Is there an
> efficient way in jgrapht?

We don't currently have the code for that; you could consider 
contributing it if you develop it.

JVS

Re: [jgrapht-users] Average path length

[Claudio M. <cla...@gm...>]

yes, that's what i want. i guess i should first transform my graph
into adjacent matrix representation in order to do so. Is there an
efficient way in jgrapht?

On Wed, Apr 29, 2009 at 9:10 PM, John V. Sichi <js...@gm...> wrote:
> Hi Claudio,
>
> You probably want to first run an all-pairs shortest path algorithm such as
> Floyd-Warshall and then analyze the results from that.
>
> http://en.wikipedia.org/wiki/Floyd-Warshall_algorithm
>
> JGraphT does not yet have this in the library.
>
> JVS
>
> Claudio Martella wrote:
>>
>> Hello list!
>>
>> I'm trying to calculate the average path length of my graph and the
>> diameter (longest shortest path).
>>
>> At the moment it's non-optimized:
>>
>> for(Vertex source: graph.vertexSet()){
>>    for(Vertex destination: graph.vertexSet()){
>>        if(!source.equals(destination)){
>>            List<DefaultWeightedEdge> path =
>> DijkstraShortestPath.findPathBetween(graph, source, destination);
>>            if(path != null)
>>                averagePathLength += path.size();
>>        }
>>    }
>> }
>> N = graph.vertexSet().size();
>> averagePathLength /= (N*(N-1));
>>
>> This code is simplified to explain you what I'm doing now. There's of
>> course a misusage of resources and computational time. Any idea what
>> is the best way to calculate average path lengths, diameter and every
>> kind of graph property that would need to calculate paths reusing
>> resources and partial solutions?
>>
>> TIA
>>
>> /CM
>>
>>
>
>



-- 
    Claudio Martella
    cla...@gm...

Re: [jgrapht-users] Average path length

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

Hi Claudio,

You probably want to first run an all-pairs shortest path algorithm such 
as Floyd-Warshall and then analyze the results from that.

http://en.wikipedia.org/wiki/Floyd-Warshall_algorithm

JGraphT does not yet have this in the library.

JVS

Claudio Martella wrote:
> Hello list!
> 
> I'm trying to calculate the average path length of my graph and the
> diameter (longest shortest path).
> 
> At the moment it's non-optimized:
> 
> for(Vertex source: graph.vertexSet()){
>     for(Vertex destination: graph.vertexSet()){
>         if(!source.equals(destination)){
>             List<DefaultWeightedEdge> path =
> DijkstraShortestPath.findPathBetween(graph, source, destination);
>             if(path != null)
>                 averagePathLength += path.size();
>         }
>     }
> }
> N = graph.vertexSet().size();
> averagePathLength /= (N*(N-1));
> 
> This code is simplified to explain you what I'm doing now. There's of
> course a misusage of resources and computational time. Any idea what
> is the best way to calculate average path lengths, diameter and every
> kind of graph property that would need to calculate paths reusing
> resources and partial solutions?
> 
> TIA
> 
> /CM
> 
> 

[jgrapht-users] Average path length

[Claudio M. <cla...@gm...>]

Hello list!

I'm trying to calculate the average path length of my graph and the
diameter (longest shortest path).

At the moment it's non-optimized:

for(Vertex source: graph.vertexSet()){
    for(Vertex destination: graph.vertexSet()){
        if(!source.equals(destination)){
            List<DefaultWeightedEdge> path =
DijkstraShortestPath.findPathBetween(graph, source, destination);
            if(path != null)
                averagePathLength += path.size();
        }
    }
}
N = graph.vertexSet().size();
averagePathLength /= (N*(N-1));

This code is simplified to explain you what I'm doing now. There's of
course a misusage of resources and computational time. Any idea what
is the best way to calculate average path lengths, diameter and every
kind of graph property that would need to calculate paths reusing
resources and partial solutions?

TIA

/CM


-- 
    Claudio Martella
    cla...@gm...

[jgrapht-users] Ask about jscrollpane in JGrapht

[Leo S. <leo...@ya...>]

Hi all,

In JGraphAdapterDemo, there is a JScrollPane with jgraph object as its component.
When I drag a vertex into an invisible part of JFrame, the scroll doesn't appear. It seems don't work.
So, a dragged vertex can't be seen again after that.

How can I show the scroll bar when a vertex is dragged to invisible area of JFrame?
So, I can use this scroll bar to see a dragged vertex....


Thanks...


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Re: [jgrapht-users] getVertex(Object o)

[Claudio M. <cla...@gm...>]

thank you john, i ended up extending the Graph with the encapsulation:
good solution.

On Tue, Apr 7, 2009 at 11:14 PM, John V. Sichi <js...@gm...> wrote:
> Your mission, should you choose to accept it, is to get Sun (IBM?) to change
> java.util.Set to allow you to "look up" an object already in the set.  Good
> luck.  JGraphT strives to follow the patterns set by java.util.
>
> For cases like this, I usually take the approach you mention of maintaining
> my own HashMap outside of the graph (in an encapsulating class).  If someone
> wanted to contributed something like a generic "KeyedGraph", that would be
> fine, but I think we should leave the existing interfaces alone.
>
> JVS
>
> Claudio Martella wrote:
>>
>> Hello to the list members.
>>
>> I write for a topic that looks kind of hot in here: the
>> Graph.getVertex() method.
>> I'm using a SimpleDirectedWeightedGraph ecl  to represent words with
>> my own WordNode class and their relationships (with a
>> DefaultWeightedEdge). Each graph vertex (a word for me) has a payload
>> for some statistics (i.e. the number of occurences in the
>> document/corpus).
>>
>> While parsing the document ( or while the application is running ) i
>> want to get access to the node to read its data. I've overidden the
>> .equals() for my WordNode class, so that it actually checks the
>> WordNode.getWord() - String, so the idea is to do a
>> graph.getVertex(new WordNode("whatever")).getOccurences()   without
>> the need to hold all the vertexes in another datastructure (like a
>> HashMap), or without surfing the expensive graph.vertexSet().
>> AFAIK, this is not possible in jgrapht. I don't actually want the
>> getVertex() to work for reference-equality, but for my value-equality
>> through the equals() "interface".
>>
>> Any suggestions?
>>
>> TIA
>>
>> Claudio Martella
>>
>
>



-- 
    Claudio Martella
    cla...@gm...

Re: [jgrapht-users] getVertex(Object o)

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

Your mission, should you choose to accept it, is to get Sun (IBM?) to 
change java.util.Set to allow you to "look up" an object already in the 
set.  Good luck.  JGraphT strives to follow the patterns set by java.util.

For cases like this, I usually take the approach you mention of 
maintaining my own HashMap outside of the graph (in an encapsulating 
class).  If someone wanted to contributed something like a generic 
"KeyedGraph", that would be fine, but I think we should leave the 
existing interfaces alone.

JVS

Claudio Martella wrote:
> Hello to the list members.
> 
> I write for a topic that looks kind of hot in here: the
> Graph.getVertex() method.
> I'm using a SimpleDirectedWeightedGraph ecl  to represent words with
> my own WordNode class and their relationships (with a
> DefaultWeightedEdge). Each graph vertex (a word for me) has a payload
> for some statistics (i.e. the number of occurences in the
> document/corpus).
> 
> While parsing the document ( or while the application is running ) i
> want to get access to the node to read its data. I've overidden the
> .equals() for my WordNode class, so that it actually checks the
> WordNode.getWord() - String, so the idea is to do a
> graph.getVertex(new WordNode("whatever")).getOccurences()   without
> the need to hold all the vertexes in another datastructure (like a
> HashMap), or without surfing the expensive graph.vertexSet().
> AFAIK, this is not possible in jgrapht. I don't actually want the
> getVertex() to work for reference-equality, but for my value-equality
> through the equals() "interface".
> 
> Any suggestions?
> 
> TIA
> 
> Claudio Martella
> 

[jgrapht-users] getVertex(Object o)

[Claudio M. <cla...@gm...>]

Hello to the list members.

I write for a topic that looks kind of hot in here: the
Graph.getVertex() method.
I'm using a SimpleDirectedWeightedGraph ecl  to represent words with
my own WordNode class and their relationships (with a
DefaultWeightedEdge). Each graph vertex (a word for me) has a payload
for some statistics (i.e. the number of occurences in the
document/corpus).

While parsing the document ( or while the application is running ) i
want to get access to the node to read its data. I've overidden the
.equals() for my WordNode class, so that it actually checks the
WordNode.getWord() - String, so the idea is to do a
graph.getVertex(new WordNode("whatever")).getOccurences()   without
the need to hold all the vertexes in another datastructure (like a
HashMap), or without surfing the expensive graph.vertexSet().
AFAIK, this is not possible in jgrapht. I don't actually want the
getVertex() to work for reference-equality, but for my value-equality
through the equals() "interface".

Any suggestions?

TIA

Claudio Martella

-- 
    Claudio Martella
    cla...@gm...

[jgrapht-users] VertexDegreeComparator with sort()

[lalitha v. <lal...@ya...>]

Hi,

I have created a simpleWeightedGraph and i have to find the nodes with top k degrees. How can i use VertexDegreeComparator with sort() function of java to do this?

Thanks
Lalitha


      

Re: [jgrapht-users] Node degree in the case of a looping edge

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

Thanks; this is definitely a bug (the test should be using equals 
instead of == in all cases).  I've checked in the fix and unit test in 
Subversion.

JVS

Michaël Michaud wrote:
> Hi,
> 
> Maybe somebody can tell me if this behaviour is normal or if it's a bug.
> I want to build a graph with a unique cycle (one edge, one vertex)
> I use two classes MyVertex and MyEdge, a WeightedPseudograph (version 
> 0.7.3 of jGraphT), and here is my test case :
> 
> v1 = new MyVertex();
> graph.addVertex(v1);
> graph.addEdge(v1,v1,new MyEdge());
> ==> build a graph with 1 vertex and 1 edge, vertex has degree 2 (that is 
> OK!)
> 
> v1 = new MyVertex();
> v2 = new MyVertex(); // where n2.equals(n1)
> graph.addVertex(v1);
> graph.addVertex(v2);
> graph.addEdge(v1,v2,new MyEdge());
> ==> build a graph with 1 vertex and 1 edge, vertex has degree 4 !
> 
> Seems like addVertex  uses equals to compare vertices and add only one 
> vertex if v1!=v2 but v1.equals(v2)
> That's fine for me
> There is still 1 vertex after addEdge, but that time, the degreeOf 
> method returns 4 instead of 2
> 
> I find this code in AbstractBaseGraph (line 1109) :
> if (source != target) {getEdgeContainer(target).addEdge(e);}
> //here == is used, not equals
> and also this (line 1125) :
> if (getEdgeSource(e).equals(getEdgeTarget(e))) { degree += 2;}
> 
> Any help is welcome
> 
> Michaël
> 
> 
> 
> ------------------------------------------------------------------------------
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> _______________________________________________
> jgrapht-users mailing list
> jgr...@li...
> https://lists.sourceforge.net/lists/listinfo/jgrapht-users
> 

[jgrapht-users] Node degree in the case of a looping edge

[Michaël M. <mic...@fr...>]

Hi,

Maybe somebody can tell me if this behaviour is normal or if it's a bug.
I want to build a graph with a unique cycle (one edge, one vertex)
I use two classes MyVertex and MyEdge, a WeightedPseudograph (version 
0.7.3 of jGraphT), and here is my test case :

v1 = new MyVertex();
graph.addVertex(v1);
graph.addEdge(v1,v1,new MyEdge());
==> build a graph with 1 vertex and 1 edge, vertex has degree 2 (that is 
OK!)

v1 = new MyVertex();
v2 = new MyVertex(); // where n2.equals(n1)
graph.addVertex(v1);
graph.addVertex(v2);
graph.addEdge(v1,v2,new MyEdge());
==> build a graph with 1 vertex and 1 edge, vertex has degree 4 !

Seems like addVertex  uses equals to compare vertices and add only one 
vertex if v1!=v2 but v1.equals(v2)
That's fine for me
There is still 1 vertex after addEdge, but that time, the degreeOf 
method returns 4 instead of 2

I find this code in AbstractBaseGraph (line 1109) :
if (source != target) {getEdgeContainer(target).addEdge(e);}
//here == is used, not equals
and also this (line 1125) :
if (getEdgeSource(e).equals(getEdgeTarget(e))) { degree += 2;}

Any help is welcome

Michaël

Re: [jgrapht-users] Load graph from file

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

Francesco Cioffi wrote:
> Hi guys,
> 
> I'm new to jgrapht and I would like to use as graph library in my Project.
> 
> I must create a graph, save it in a file, and then reload it for some purpose.
> 
> I have found some utilities for exporting but I don't found utilities
> for load a graph from a file.
> 
> 
> Can you suggest me, how can I do that?

Right, we currently only have exporters, without importers.  However, 
most JGraphT data structures implement Serializable, so that is one 
option for persistence, although I personally am not a big fan of it due 
to issues like incompatibilities during migration to newer versions.

JVS

[jgrapht-users] Load graph from file

[Francesco C. <fc...@gm...>]

Hi guys,

I'm new to jgrapht and I would like to use as graph library in my Project.

I must create a graph, save it in a file, and then reload it for some purpose.

I have found some utilities for exporting but I don't found utilities
for load a graph from a file.


Can you suggest me, how can I do that?



Thank you,
Francesco Cioffi

Re: [jgrapht-users] Question on JGraphT

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

Thanks Guillaume.  I'll poke around a bit and update the Javadoc with 
what I find.

Olivier, if you are interested in implementing one of the newer 
algorithms, we can incorporate that into the library too.

JVS

gu boulmi wrote:
> Hi,
>  
> I have not implemented this algorithm based on a reference paper. So, 
> it's not Jimenez and Marzal!
> Though I'm sure that what I've written is not new and must have 
> been explained previously in many papers.
>  
> The algorithm is a *variant of the Bellman-Ford algorithm* but instead 
> of only storing the best path I store the "*k*" best paths at each pass 
> (se differences between methods KShortestPathsIterator#next and 
> BellmanFordIterator#next).
>  
> Complexity "*/m*n/*" is because it's a variant of Bellman-Ford (whose 
> complexity is /*O(m*n)*/) and the "*/k/*" factor is because the method 
> RankingPathElementList#addPathElements is /*O(k)*/ where *k* is the 
> number of expected paths to be computed (by the way I notice that this 
> "O(k)" piece of information is not in the javadoc documentation).
>  
> If you find a paper pointing to this kind of algorithm, feel free to 
> update the javadoc documentation.
>  
> Regards,
>  
> Guillaume
> 
> --- En date de : *Mer 4.3.09, John V. Sichi /<js...@gm...>/* a écrit :
> 
>     De: John V. Sichi <js...@gm...>
>     Objet: Re: Question on JGraphT
>     À: lef...@ya...
>     Cc: jgr...@li..., bou...@ya...
>     Date: Mercredi 4 Mars 2009, 1h09
> 
>     Olivier Lefevre wrote:
>     > Hi,
>     > 
>     > What is the algorithm used for K-shortest paths in JGraphT: the REA
>     algorithm of Jimenez and Marzal?
>     > 
>     > Regards,
>     > 
>     > Olivier Lefevre
>     > Freelance bioinformatics developer
>     > Berlin, Germany
> 
>     Greetings Olivier,
> 
>     I don't know the answer, so I'm cc'ing your question to the users
>     mailing list, as well as Guillaume Boulmier, who developed this code.
> 
>     Jimenez and Marzal is O(m+Knlog(m/n)), whereas Guillaume's comments have
>     O(K*m*n) for the running time.
> 
>     JVS
> 
> 

Re: [jgrapht-users] How to get subgraph of a graph?

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

maria esther sanchez wrote:
> I was wondering if there is a method in JGraphT to get the aislated 
> subgraphs inside a graph? (Like the graphs inside a graph)

To find them, you can use org.jgrapht.alg.ConnectivityInspector or 
StrongConnectivityInspector.

To manipulate them individually once you find them, you can use 
org.jgrapht.graph.Subgraph (or one of its variants such as 
DirectedSubgraph).

JVS

Re: [jgrapht-users] Question on JGraphT

[gu b. <bou...@ya...>]

Hi,
 
I have not implemented this algorithm based on a reference paper. So, it's not Jimenez and Marzal!
Though I'm sure that what I've written is not new and must have been explained previously in many papers.
 
The algorithm is a variant of the Bellman-Ford algorithm but instead of only storing the best path I store the "k" best paths at each pass (se differences between methods KShortestPathsIterator#next and BellmanFordIterator#next).
 
Complexity "m*n" is because it's a variant of Bellman-Ford (whose complexity is O(m*n)) and the "k" factor is because the method RankingPathElementList#addPathElements is O(k) where k is the number of expected paths to be computed (by the way I notice that this "O(k)" piece of information is not in the javadoc documentation).
 
If you find a paper pointing to this kind of algorithm, feel free to update the javadoc documentation.
 
Regards,
 
Guillaume

--- En date de : Mer 4.3.09, John V. Sichi <js...@gm...> a écrit :

De: John V. Sichi <js...@gm...>
Objet: Re: Question on JGraphT
À: lef...@ya...
Cc: jgr...@li..., bou...@ya...
Date: Mercredi 4 Mars 2009, 1h09

Olivier Lefevre wrote:
> Hi,
> 
> What is the algorithm used for K-shortest paths in JGraphT: the REA
algorithm of Jimenez and Marzal?
> 
> Regards,
> 
> Olivier Lefevre
> Freelance bioinformatics developer
> Berlin, Germany

Greetings Olivier,

I don't know the answer, so I'm cc'ing your question to the users
mailing list, as well as Guillaume Boulmier, who developed this code.

Jimenez and Marzal is O(m+Knlog(m/n)), whereas Guillaume's comments have
O(K*m*n) for the running time.

JVS



      

Re: [jgrapht-users] Question on JGraphT

[gu b. <bou...@ya...>]

Hi,
 
I have not implemented this algorithm based on a reference paper, though I'm sure that what I've written is not new and must have been explained previously in many papers.
 
The algorithm is a variant of the Bellman-Ford algorithm but instead of only storing the best path I store the "k" best paths at each pass (se differences between KShortestPathsIterator#next and BellmanFordIterator#next).
 
Complexity "m*n" is because it's a variant of Bellman-Ford and the "k" factor is because the method RankingPathElementList#addPathElements is O(k).
 
If you find  
 

--- En date de : Mer 4.3.09, John V. Sichi <js...@gm...> a écrit :

De: John V. Sichi <js...@gm...>
Objet: Re: Question on JGraphT
À: lef...@ya...
Cc: jgr...@li..., bou...@ya...
Date: Mercredi 4 Mars 2009, 1h09

Olivier Lefevre wrote:
> Hi,
> 
> What is the algorithm used for K-shortest paths in JGraphT: the REA
algorithm of Jimenez and Marzal?
> 
> Regards,
> 
> Olivier Lefevre
> Freelance bioinformatics developer
> Berlin, Germany

Greetings Olivier,

I don't know the answer, so I'm cc'ing your question to the users
mailing list, as well as Guillaume Boulmier, who developed this code.

Jimenez and Marzal is O(m+Knlog(m/n)), whereas Guillaume's comments have
O(K*m*n) for the running time.

JVS



      

Re: [jgrapht-users] Question on JGraphT

[gu b. <bou...@ya...>]

Hi,
 
I'm Implmentation

--- En date de : Mer 4.3.09, John V. Sichi <js...@gm...> a écrit :

De: John V. Sichi <js...@gm...>
Objet: Re: Question on JGraphT
À: lef...@ya...
Cc: jgr...@li..., bou...@ya...
Date: Mercredi 4 Mars 2009, 1h09

Olivier Lefevre wrote:
> Hi,
> 
> What is the algorithm used for K-shortest paths in JGraphT: the REA
algorithm of Jimenez and Marzal?
> 
> Regards,
> 
> Olivier Lefevre
> Freelance bioinformatics developer
> Berlin, Germany

Greetings Olivier,

I don't know the answer, so I'm cc'ing your question to the users
mailing list, as well as Guillaume Boulmier, who developed this code.

Jimenez and Marzal is O(m+Knlog(m/n)), whereas Guillaume's comments have
O(K*m*n) for the running time.

JVS



      

Re: [jgrapht-users] Troubless with references...

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

maria esther sanchez wrote:
> Hello! I am having trouble with the references. I would like to know how 
> to duplicate, clone or copy a graph in with there are no references amog 
> them. I tryed this method: Graphs.addGraph(simpleGraph,graph)... but i 
> still have the same problem. If a modify a vertex from simplegrap, the 
> node that corresponds to graph is modified also.
> How can i make a copy that does afect  from the graph that i am copying, 
> and the other way arround.
> Thank u for you help!

Hi Maria,

You can code this as follows:

1) create a Map<V,V> m

2) write a new cloneAllVertices like addAllVertices which does vPrime = 
v.clone(), adds an entry (v,vPrime) to m, and puts vPrime in the 
destination graph

3) write a new addAllEdgesForClones like addAllEdges which uses m to map 
each s and t to sPrime and tPrime before calling addEdge

I forget how the interactions between generics and clone work out, but 
if you get a generic version of this working along with a unit test, 
please send it to me and I'll check it in as a new utility method on 
class org.jgrapht.Graphs.

JVS

Re: [jgrapht-users] Bidirectional Edges

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

Bhavesh Sanghvi wrote:
> I am interested in a digraph which may also contain bidirectional edges 
> (preferably with weight). Later, I wish to detect cycles this graph 
> (specifically for this reason, I cannot use two directional edges as 
> they would be identified in the cycle).
> 
>  
> 
> Please let me know if it is possible to create such a graph using 
> JGraphT. I searched for bidirectional edges, however, was not able to 
> find it.

Hi Bhavesh,

Following the Mathworld definition,

http://mathworld.wolfram.com/DirectedGraph.html

a bidirectional edge is equivalent to a pair of oppositely-directed edges.

The ability to mix directed with undirected edges in the same graph 
isn't something we're planning to add since it is an uncommon 
requirement and would complicate the internals considerably.

Perhaps you could you can write a modified version of the cycle detector 
which ignores cycles of length 2?

JVS

[jgrapht-users] Troubless with references...

[maria e. s. <tet...@ho...>]

Hello! I am having trouble with the references. I would like to know how to duplicate, clone or copy a graph in with there are no references amog them. I tryed this method: Graphs.addGraph(simpleGraph,graph)... but i still have the same problem. If a modify a vertex from simplegrap, the node that corresponds to graph is modified also. 

How can i make a copy that does afect  from the graph that i am copying, and the other way arround.

Thank u for you help!

Atte tete

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[jgrapht-users] Bidirectional Edges

[Bhavesh S. <bsa...@cs...>]

Hello,

 

I am interested in a digraph which may also contain bidirectional edges
(preferably with weight). Later, I wish to detect cycles this graph
(specifically for this reason, I cannot use two directional edges as they
would be identified in the cycle).

 

Please let me know if it is possible to create such a graph using JGraphT. I
searched for bidirectional edges, however, was not able to find it.

 

Thanks for your help!

 

--

Thanks & regards,

Bhavesh Sanghvi

 

P.S. Please excuse me for cross-posting on both forum and mailing list. I
was not sure if they are synched or not.

 

Re: [jgrapht-users] Question on JGraphT

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

Olivier Lefevre wrote:
> Hi,
> 
> What is the algorithm used for K-shortest paths in JGraphT: 
> the REA algorithm of Jimenez and Marzal?
> 
> Regards,
> 
> Olivier Lefevre
> Freelance bioinformatics developer
> Berlin, Germany

Greetings Olivier,

I don't know the answer, so I'm cc'ing your question to the users 
mailing list, as well as Guillaume Boulmier, who developed this code.

Jimenez and Marzal is O(m+Knlog(m/n)), whereas Guillaume's comments have 
O(K*m*n) for the running time.

JVS

Re: [jgrapht-users] Access elements of Set<V>

[Jonathan C. <jon...@it...>]

This is not really a JGraphT-related question. A set of vertices is  
just any set. Refer to the standard Javadoc on questions about the  
collections framework: http://java.sun.com/javase/6/docs/api/java/util/Collection.html

/Jonathan

20 feb 2009 kl. 22.43 skrev padma priya:

> Hi,
> I have a set of vertices in Set<V>. How do I access them individually?
> I want the elements of Set<V> so that I can do some manipulations  
> with them.
> Please do let me know.
>
> Thank you,
> Padma dubasi.
>
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