Re: [Neo4j] Function to check whether two nodes are connected?
Just a heads up here:
if (r.getType().equals(rel.getType()))
isn't accurate. If you read the javadocs you can see that you cannot compare
RelationshipType instances, but rather their names or use the short-hand
method on Relationship:
if (r.isType(rel.getType()))
2011/10/27 Bruno Paiva Lima da Silva bplsi...@gmail.com
Easy: just one.
For now, I've written this, but I'm still not sure it is the simplest
way to write it
public boolean areConnected(Node n1,Node n2,Relationship
rel,Direction dir) throws Exception {
IterableRelationship relationships = n1.getRelationships(dir);
for (Relationship r : relationships) {
//I am only working with Dynamic Relationships
if (r.getType().equals(rel.getType())) {
if (dir == Direction.OUTGOING) { if
(r.getEndNode().equals(n2)) { return true; } }
else { if (r.getStartNode().equals(n2)) { return true; } }
}
}
return false;
}
Bruno
Le 27/10/2011 18:31, Peter Neubauer a écrit :
Bruno,
There is no such function low level, but toy can use a Shortest path algo
to
check this. What is the maximum length for a path between the nodes?
On Oct 27, 2011 6:14 PM, Bruno Paiva Lima da Silvabplsi...@gmail.com
wrote:
Hello there!
First of all, thanks for the help in all my previous questions, all the
answers have been helping me to use Neo4j with success.
I have a very simple question, but I haven't found the answer yet...
I'd like to have a function, which signature would be more or less like
this:
public areTheyConnected(Node *n1*,Node *n2*,Relationship *rel*,Direction
*dir*)
which returns true iff there is an edge of type *rel*, between *n1* and
*n2*, in the *dir* direction (the direction has n1 as reference).
Example:
In my graph, I have: Bob knows Tom, Tom knows Peter, Jack knows Tom
areTheyConnected(nodeBob,nodeTom,relKnows,Direction.OUTGOING) returns
true; (Bob knows Tom)
areTheyConnected(nodeTom,nodeJack,relKnows,Direction.INCOMING) also
returns true; (Jack knows Tom)
areTheyConnected(nodeBob,nodeTom,relKnows,Direction.INCOMING) returns
false; (Tom doesn't know Bob)
Is there an easy method (constant time, or close) for that?
Thank you very much,
Bruno
___
Neo4j mailing list
User@lists.neo4j.org
https://lists.neo4j.org/mailman/listinfo/user
___
Neo4j mailing list
User@lists.neo4j.org
https://lists.neo4j.org/mailman/listinfo/user
___
Neo4j mailing list
User@lists.neo4j.org
https://lists.neo4j.org/mailman/listinfo/user
--
Mattias Persson, [matt...@neotechnology.com]
Hacker, Neo Technology
www.neotechnology.com
___
Neo4j mailing list
User@lists.neo4j.org
https://lists.neo4j.org/mailman/listinfo/user
Re: [Neo4j] Function to check whether two nodes are connected?
Bruno, There is no such function low level, but toy can use a Shortest path algo to check this. What is the maximum length for a path between the nodes? On Oct 27, 2011 6:14 PM, Bruno Paiva Lima da Silva bplsi...@gmail.com wrote: Hello there! First of all, thanks for the help in all my previous questions, all the answers have been helping me to use Neo4j with success. I have a very simple question, but I haven't found the answer yet... I'd like to have a function, which signature would be more or less like this: public areTheyConnected(Node *n1*,Node *n2*,Relationship *rel*,Direction *dir*) which returns true iff there is an edge of type *rel*, between *n1* and *n2*, in the *dir* direction (the direction has n1 as reference). Example: In my graph, I have: Bob knows Tom, Tom knows Peter, Jack knows Tom areTheyConnected(nodeBob,nodeTom,relKnows,Direction.OUTGOING) returns true; (Bob knows Tom) areTheyConnected(nodeTom,nodeJack,relKnows,Direction.INCOMING) also returns true; (Jack knows Tom) areTheyConnected(nodeBob,nodeTom,relKnows,Direction.INCOMING) returns false; (Tom doesn't know Bob) Is there an easy method (constant time, or close) for that? Thank you very much, Bruno ___ Neo4j mailing list User@lists.neo4j.org https://lists.neo4j.org/mailman/listinfo/user ___ Neo4j mailing list User@lists.neo4j.org https://lists.neo4j.org/mailman/listinfo/user
Re: [Neo4j] Function to check whether two nodes are connected?
Easy: just one.
For now, I've written this, but I'm still not sure it is the simplest
way to write it
public boolean areConnected(Node n1,Node n2,Relationship
rel,Direction dir) throws Exception {
IterableRelationship relationships = n1.getRelationships(dir);
for (Relationship r : relationships) {
//I am only working with Dynamic Relationships
if (r.getType().equals(rel.getType())) {
if (dir == Direction.OUTGOING) { if
(r.getEndNode().equals(n2)) { return true; } }
else { if (r.getStartNode().equals(n2)) { return true; } }
}
}
return false;
}
Bruno
Le 27/10/2011 18:31, Peter Neubauer a écrit :
Bruno,
There is no such function low level, but toy can use a Shortest path algo to
check this. What is the maximum length for a path between the nodes?
On Oct 27, 2011 6:14 PM, Bruno Paiva Lima da Silvabplsi...@gmail.com
wrote:
Hello there!
First of all, thanks for the help in all my previous questions, all the
answers have been helping me to use Neo4j with success.
I have a very simple question, but I haven't found the answer yet...
I'd like to have a function, which signature would be more or less like
this:
public areTheyConnected(Node *n1*,Node *n2*,Relationship *rel*,Direction
*dir*)
which returns true iff there is an edge of type *rel*, between *n1* and
*n2*, in the *dir* direction (the direction has n1 as reference).
Example:
In my graph, I have: Bob knows Tom, Tom knows Peter, Jack knows Tom
areTheyConnected(nodeBob,nodeTom,relKnows,Direction.OUTGOING) returns
true; (Bob knows Tom)
areTheyConnected(nodeTom,nodeJack,relKnows,Direction.INCOMING) also
returns true; (Jack knows Tom)
areTheyConnected(nodeBob,nodeTom,relKnows,Direction.INCOMING) returns
false; (Tom doesn't know Bob)
Is there an easy method (constant time, or close) for that?
Thank you very much,
Bruno
___
Neo4j mailing list
User@lists.neo4j.org
https://lists.neo4j.org/mailman/listinfo/user
___
Neo4j mailing list
User@lists.neo4j.org
https://lists.neo4j.org/mailman/listinfo/user
___
Neo4j mailing list
User@lists.neo4j.org
https://lists.neo4j.org/mailman/listinfo/user
Re: [Neo4j] Function to check whether two nodes are connected?
There is one caveat to this method, you'd have to know which node is most
densely connected.
Suppose one of the nodes has 100,000 relationships (incoming and outgoing) and
the other node has only a few relationships, then you'd want to iterate over
the relationships of the second node.
A solution could be to iterate over both sets of relationships at the same time:
public boolean areConnected(Node n1,Node n2, RelationshipType relType,Direction
dir) {
IteratorRelatiionship rels1 = n1.getRelationships(relType, dir).iterator();
IteratorRelatiionship rels2 = n2.getRelationships(relType, dir).iterator();
while(rels1.hasNext rels2.hasNext){
Relationship rel1 = rels1.next();
Relationship rel2 = rels2.next();
if (rel1.getEndNode().equals(n2)
return true;
else if (rel2.getEndNode().equals(n1))
return true;
}
return false;
}
Date: Thu, 27 Oct 2011 18:39:01 +0200
From: bplsi...@gmail.com
To: user@lists.neo4j.org
Subject: Re: [Neo4j] Function to check whether two nodes are connected?
Easy: just one.
For now, I've written this, but I'm still not sure it is the simplest
way to write it
public boolean areConnected(Node n1,Node n2,Relationship
rel,Direction dir) throws Exception {
IterableRelationship relationships = n1.getRelationships(dir);
for (Relationship r : relationships) {
//I am only working with Dynamic Relationships
if (r.getType().equals(rel.getType())) {
if (dir == Direction.OUTGOING) { if
(r.getEndNode().equals(n2)) { return true; } }
else { if (r.getStartNode().equals(n2)) { return true; } }
}
}
return false;
}
Bruno
Le 27/10/2011 18:31, Peter Neubauer a écrit :
Bruno,
There is no such function low level, but toy can use a Shortest path algo to
check this. What is the maximum length for a path between the nodes?
On Oct 27, 2011 6:14 PM, Bruno Paiva Lima da Silvabplsi...@gmail.com
wrote:
Hello there!
First of all, thanks for the help in all my previous questions, all the
answers have been helping me to use Neo4j with success.
I have a very simple question, but I haven't found the answer yet...
I'd like to have a function, which signature would be more or less like
this:
public areTheyConnected(Node *n1*,Node *n2*,Relationship *rel*,Direction
*dir*)
which returns true iff there is an edge of type *rel*, between *n1* and
*n2*, in the *dir* direction (the direction has n1 as reference).
Example:
In my graph, I have: Bob knows Tom, Tom knows Peter, Jack knows Tom
areTheyConnected(nodeBob,nodeTom,relKnows,Direction.OUTGOING) returns
true; (Bob knows Tom)
areTheyConnected(nodeTom,nodeJack,relKnows,Direction.INCOMING) also
returns true; (Jack knows Tom)
areTheyConnected(nodeBob,nodeTom,relKnows,Direction.INCOMING) returns
false; (Tom doesn't know Bob)
Is there an easy method (constant time, or close) for that?
Thank you very much,
Bruno
___
Neo4j mailing list
User@lists.neo4j.org
https://lists.neo4j.org/mailman/listinfo/user
___
Neo4j mailing list
User@lists.neo4j.org
https://lists.neo4j.org/mailman/listinfo/user
___
Neo4j mailing list
User@lists.neo4j.org
https://lists.neo4j.org/mailman/listinfo/user
___
Neo4j mailing list
User@lists.neo4j.org
https://lists.neo4j.org/mailman/listinfo/user
Re: [Neo4j] Function to check whether two nodes are connected?
I see I made a bit of a mistake with this one. The gist of the solution
remains, but I made a mistake dealing with the directions of relationship.
It should be something like this.
public boolean areConnected(Node n1,Node n2, RelationshipType relType,Direction
dir) {
Direction dir2 = null;
if(dir.equals(Direction.INCOMING))
dir2 = Direction.OUTGOING;
else if(dir.equals(Direction.OUTGOING))
dir2 = Direction.INCOMING;
else dir2 = Direction.BOTH;
IteratorRelationship rels1 = n1.getRelationships(relType, dir).iterator();
IteratorRelationship rels2 = n2.getRelationships(relType, dir2).iterator();
while(rels1.hasNext rels2.hasNext){
Relationship rel1 = rels1.next();
Relationship rel2 = rels2.next();
if (rel1.getEndNode().equals(n2)
return true;
else if (rel2.getEndNode().equals(n1))
return true;
}
return false;
}
From: pd_aficion...@hotmail.com
To: user@lists.neo4j.org
Date: Thu, 27 Oct 2011 19:05:16 +0200
Subject: Re: [Neo4j] Function to check whether two nodes are connected?
There is one caveat to this method, you'd have to know which node is most
densely connected.
Suppose one of the nodes has 100,000 relationships (incoming and outgoing)
and the other node has only a few relationships, then you'd want to iterate
over the relationships of the second node.
A solution could be to iterate over both sets of relationships at the same
time:
public boolean areConnected(Node n1,Node n2, RelationshipType
relType,Direction dir) {
IteratorRelatiionship rels1 = n1.getRelationships(relType,
dir).iterator();
IteratorRelatiionship rels2 = n2.getRelationships(relType,
dir).iterator();
while(rels1.hasNext rels2.hasNext){
Relationship rel1 = rels1.next();
Relationship rel2 = rels2.next();
if (rel1.getEndNode().equals(n2)
return true;
else if (rel2.getEndNode().equals(n1))
return true;
}
return false;
}
Date: Thu, 27 Oct 2011 18:39:01 +0200
From: bplsi...@gmail.com
To: user@lists.neo4j.org
Subject: Re: [Neo4j] Function to check whether two nodes are connected?
Easy: just one.
For now, I've written this, but I'm still not sure it is the simplest
way to write it
public boolean areConnected(Node n1,Node n2,Relationship
rel,Direction dir) throws Exception {
IterableRelationship relationships = n1.getRelationships(dir);
for (Relationship r : relationships) {
//I am only working with Dynamic Relationships
if (r.getType().equals(rel.getType())) {
if (dir == Direction.OUTGOING) { if
(r.getEndNode().equals(n2)) { return true; } }
else { if (r.getStartNode().equals(n2)) { return true; } }
}
}
return false;
}
Bruno
Le 27/10/2011 18:31, Peter Neubauer a écrit :
Bruno,
There is no such function low level, but toy can use a Shortest path algo
to
check this. What is the maximum length for a path between the nodes?
On Oct 27, 2011 6:14 PM, Bruno Paiva Lima da Silvabplsi...@gmail.com
wrote:
Hello there!
First of all, thanks for the help in all my previous questions, all the
answers have been helping me to use Neo4j with success.
I have a very simple question, but I haven't found the answer yet...
I'd like to have a function, which signature would be more or less like
this:
public areTheyConnected(Node *n1*,Node *n2*,Relationship *rel*,Direction
*dir*)
which returns true iff there is an edge of type *rel*, between *n1* and
*n2*, in the *dir* direction (the direction has n1 as reference).
Example:
In my graph, I have: Bob knows Tom, Tom knows Peter, Jack knows Tom
areTheyConnected(nodeBob,nodeTom,relKnows,Direction.OUTGOING) returns
true; (Bob knows Tom)
areTheyConnected(nodeTom,nodeJack,relKnows,Direction.INCOMING) also
returns true; (Jack knows Tom)
areTheyConnected(nodeBob,nodeTom,relKnows,Direction.INCOMING) returns
false; (Tom doesn't know Bob)
Is there an easy method (constant time, or close) for that?
Thank you very much,
Bruno
___
Neo4j mailing list
User@lists.neo4j.org
https://lists.neo4j.org/mailman/listinfo/user
___
Neo4j mailing list
User@lists.neo4j.org
https://lists.neo4j.org/mailman/listinfo/user
___
Neo4j mailing list
User@lists.neo4j.org
https://lists.neo4j.org/mailman/listinfo/user
___
Neo4j mailing list
User@lists.neo4j.org
https://lists.neo4j.org/mailman/listinfo/user
___
Neo4j mailing list
User@lists.neo4j.org
https://lists.neo4j.org/mailman/listinfo
Re: [Neo4j] Function to check whether two nodes are connected?
Good catch Niels, thanks - my brain is in jet lag mode :-\
On Oct 27, 2011 7:26 PM, Niels Hoogeveen pd_aficion...@hotmail.com
wrote:
I see I made a bit of a mistake with this one. The gist of the solution
remains, but I made a mistake dealing with the directions of relationship.
It should be something like this.
public boolean areConnected(Node n1,Node n2, RelationshipType
relType,Direction dir) {
Direction dir2 = null;
if(dir.equals(Direction.INCOMING))
dir2 = Direction.OUTGOING;
else if(dir.equals(Direction.OUTGOING))
dir2 = Direction.INCOMING;
else dir2 = Direction.BOTH;
IteratorRelationship rels1 = n1.getRelationships(relType,
dir).iterator();
IteratorRelationship rels2 = n2.getRelationships(relType,
dir2).iterator();
while(rels1.hasNext rels2.hasNext){
Relationship rel1 = rels1.next();
Relationship rel2 = rels2.next();
if (rel1.getEndNode().equals(n2)
return true;
else if (rel2.getEndNode().equals(n1))
return true;
}
return false;
}
From: pd_aficion...@hotmail.com
To: user@lists.neo4j.org
Date: Thu, 27 Oct 2011 19:05:16 +0200
Subject: Re: [Neo4j] Function to check whether two nodes are connected?
There is one caveat to this method, you'd have to know which node is
most densely connected.
Suppose one of the nodes has 100,000 relationships (incoming and
outgoing) and the other node has only a few relationships, then you'd want
to iterate over the relationships of the second node.
A solution could be to iterate over both sets of relationships at the
same time:
public boolean areConnected(Node n1,Node n2, RelationshipType
relType,Direction dir) {
IteratorRelatiionship rels1 = n1.getRelationships(relType,
dir).iterator();
IteratorRelatiionship rels2 = n2.getRelationships(relType,
dir).iterator();
while(rels1.hasNext rels2.hasNext){
Relationship rel1 = rels1.next();
Relationship rel2 = rels2.next();
if (rel1.getEndNode().equals(n2)
return true;
else if (rel2.getEndNode().equals(n1))
return true;
}
return false;
}
Date: Thu, 27 Oct 2011 18:39:01 +0200
From: bplsi...@gmail.com
To: user@lists.neo4j.org
Subject: Re: [Neo4j] Function to check whether two nodes are connected?
Easy: just one.
For now, I've written this, but I'm still not sure it is the simplest
way to write it
public boolean areConnected(Node n1,Node n2,Relationship
rel,Direction dir) throws Exception {
IterableRelationship relationships =
n1.getRelationships(dir);
for (Relationship r : relationships) {
//I am only working with Dynamic Relationships
if (r.getType().equals(rel.getType())) {
if (dir == Direction.OUTGOING) { if
(r.getEndNode().equals(n2)) { return true; } }
else { if (r.getStartNode().equals(n2)) { return
true; } }
}
}
return false;
}
Bruno
Le 27/10/2011 18:31, Peter Neubauer a écrit :
Bruno,
There is no such function low level, but toy can use a Shortest path
algo to
check this. What is the maximum length for a path between the nodes?
On Oct 27, 2011 6:14 PM, Bruno Paiva Lima da Silva
bplsi...@gmail.com
wrote:
Hello there!
First of all, thanks for the help in all my previous questions, all
the
answers have been helping me to use Neo4j with success.
I have a very simple question, but I haven't found the answer yet...
I'd like to have a function, which signature would be more or less
like
this:
public areTheyConnected(Node *n1*,Node *n2*,Relationship
*rel*,Direction
*dir*)
which returns true iff there is an edge of type *rel*, between *n1*
and
*n2*, in the *dir* direction (the direction has n1 as reference).
Example:
In my graph, I have: Bob knows Tom, Tom knows Peter, Jack knows
Tom
areTheyConnected(nodeBob,nodeTom,relKnows,Direction.OUTGOING)
returns
true; (Bob knows Tom)
areTheyConnected(nodeTom,nodeJack,relKnows,Direction.INCOMING) also
returns true; (Jack knows Tom)
areTheyConnected(nodeBob,nodeTom,relKnows,Direction.INCOMING)
returns
false; (Tom doesn't know Bob)
Is there an easy method (constant time, or close) for that?
Thank you very much,
Bruno
___
Neo4j mailing list
User@lists.neo4j.org
https://lists.neo4j.org/mailman/listinfo/user
___
Neo4j mailing list
User@lists.neo4j.org
https://lists.neo4j.org/mailman/listinfo/user
___
Neo4j mailing list
User@lists.neo4j.org
https://lists.neo4j.org/mailman/listinfo/user
___
Neo4j mailing list
User@lists.neo4j.org
https
Re: [Neo4j] Function to check whether two nodes are connected?
You know me and my obsession for densely connected nodes :-)
Date: Thu, 27 Oct 2011 17:37:07 +
From: peter.neuba...@neotechnology.com
To: user@lists.neo4j.org
Subject: Re: [Neo4j] Function to check whether two nodes are connected?
Good catch Niels, thanks - my brain is in jet lag mode :-\
On Oct 27, 2011 7:26 PM, Niels Hoogeveen pd_aficion...@hotmail.com
wrote:
I see I made a bit of a mistake with this one. The gist of the solution
remains, but I made a mistake dealing with the directions of relationship.
It should be something like this.
public boolean areConnected(Node n1,Node n2, RelationshipType
relType,Direction dir) {
Direction dir2 = null;
if(dir.equals(Direction.INCOMING))
dir2 = Direction.OUTGOING;
else if(dir.equals(Direction.OUTGOING))
dir2 = Direction.INCOMING;
else dir2 = Direction.BOTH;
IteratorRelationship rels1 = n1.getRelationships(relType,
dir).iterator();
IteratorRelationship rels2 = n2.getRelationships(relType,
dir2).iterator();
while(rels1.hasNext rels2.hasNext){
Relationship rel1 = rels1.next();
Relationship rel2 = rels2.next();
if (rel1.getEndNode().equals(n2)
return true;
else if (rel2.getEndNode().equals(n1))
return true;
}
return false;
}
From: pd_aficion...@hotmail.com
To: user@lists.neo4j.org
Date: Thu, 27 Oct 2011 19:05:16 +0200
Subject: Re: [Neo4j] Function to check whether two nodes are connected?
There is one caveat to this method, you'd have to know which node is
most densely connected.
Suppose one of the nodes has 100,000 relationships (incoming and
outgoing) and the other node has only a few relationships, then you'd want
to iterate over the relationships of the second node.
A solution could be to iterate over both sets of relationships at the
same time:
public boolean areConnected(Node n1,Node n2, RelationshipType
relType,Direction dir) {
IteratorRelatiionship rels1 = n1.getRelationships(relType,
dir).iterator();
IteratorRelatiionship rels2 = n2.getRelationships(relType,
dir).iterator();
while(rels1.hasNext rels2.hasNext){
Relationship rel1 = rels1.next();
Relationship rel2 = rels2.next();
if (rel1.getEndNode().equals(n2)
return true;
else if (rel2.getEndNode().equals(n1))
return true;
}
return false;
}
Date: Thu, 27 Oct 2011 18:39:01 +0200
From: bplsi...@gmail.com
To: user@lists.neo4j.org
Subject: Re: [Neo4j] Function to check whether two nodes are connected?
Easy: just one.
For now, I've written this, but I'm still not sure it is the simplest
way to write it
public boolean areConnected(Node n1,Node n2,Relationship
rel,Direction dir) throws Exception {
IterableRelationship relationships =
n1.getRelationships(dir);
for (Relationship r : relationships) {
//I am only working with Dynamic Relationships
if (r.getType().equals(rel.getType())) {
if (dir == Direction.OUTGOING) { if
(r.getEndNode().equals(n2)) { return true; } }
else { if (r.getStartNode().equals(n2)) { return
true; } }
}
}
return false;
}
Bruno
Le 27/10/2011 18:31, Peter Neubauer a écrit :
Bruno,
There is no such function low level, but toy can use a Shortest path
algo to
check this. What is the maximum length for a path between the nodes?
On Oct 27, 2011 6:14 PM, Bruno Paiva Lima da Silva
bplsi...@gmail.com
wrote:
Hello there!
First of all, thanks for the help in all my previous questions, all
the
answers have been helping me to use Neo4j with success.
I have a very simple question, but I haven't found the answer yet...
I'd like to have a function, which signature would be more or less
like
this:
public areTheyConnected(Node *n1*,Node *n2*,Relationship
*rel*,Direction
*dir*)
which returns true iff there is an edge of type *rel*, between *n1*
and
*n2*, in the *dir* direction (the direction has n1 as reference).
Example:
In my graph, I have: Bob knows Tom, Tom knows Peter, Jack knows
Tom
areTheyConnected(nodeBob,nodeTom,relKnows,Direction.OUTGOING)
returns
true; (Bob knows Tom)
areTheyConnected(nodeTom,nodeJack,relKnows,Direction.INCOMING) also
returns true; (Jack knows Tom)
areTheyConnected(nodeBob,nodeTom,relKnows,Direction.INCOMING)
returns
false; (Tom doesn't know Bob)
Is there an easy method (constant time, or close) for that?
Thank you very much,
Bruno
___
Neo4j mailing list
User@lists.neo4j.org
https://lists.neo4j.org/mailman/listinfo/user
