The advantage of tonys approach is, that it avoids potential unnecessary
loops when it finds the neighbour. Your loop iterates always over all
edges. Maybe that could make a Difference performance wise...
Am 27.09.2013 11:22 schrieb "Beth Kar" <[log in to unmask]>:

> Thank you very much for your prompt response. And actually, before
> receiving
> your replies I kind of figured out a solution. My approach was the similar
> to the one that Tony proposed. But instead of using a while loop I did
> this:
>
> Bag edges = mynetwork.getEdges(agentA, null);
> int length = edges.size();
> boolean exists = false;
>
> for (int node=0; node<len; node++){
> Edge e = (Edge)(edges.get(node));
> if(e.getOtherNode(agentA) == agentB){
>         exists = true;
> }else{continue;}
> }
>
> if (!exists){
> mynetwork.addEdge(agentA, agentB, null);
> }
>
> Thank you again,
> Beth
>
> On Thu, 26 Sep 2013 15:24:26 -0400, Joey Harrison <[log in to unmask]> wrote:
>
> >Ahh, my mistake.
> >
> >Joey
> >
> >
> >On Thu, Sep 26, 2013 at 2:38 PM, Tony Bigbee <[log in to unmask]>
> wrote:
> >
> >> That won't work.  getEdges returns a bag of Edge not Node objects.  You
> >> have to inspect each Edge looking for the neighbor agentB.
> >> I made the same mistake in my first prototype, hoping I could chain
> calls
> >> together in one line...
> >>
> >>
> >>
> >> On Thu, Sep 26, 2013 at 12:05 PM, Joey Harrison <[log in to unmask]>
> wrote:
> >>
> >>> Bag has a contains method, so you can just do this:
> >>>
> >>> network.getEdges(agentA, null).contains(agentB)
> >>>
> >>> Joey
> >>>
> >>>
> >>> On Thu, Sep 26, 2013 at 12:07 PM, Tony Bigbee <[log in to unmask]
> >wrote:
> >>>
> >>>> I couldn't find a method in sim.field.network.Network like
> >>>> areNeighbors(Object o1, Object o2).
> >>>>
> >>>> So a starting point would be to use Network's getEdges method and
> >>>> iterate through the returned Bag looking for the other agent node in
> the
> >>>> edges.    You could write a thin wrapper method to do the job and you
> would
> >>>> have a reusable component, like:
> >>>>
> >>>> public boolean areNeighbors(Network network, Object agentA, Object
> >>>> agentB) {
> >>>>     Bag edges = network.getEdges(agentA, null);  //obtain all edges
> that
> >>>> have agentA; the bag may be empty but it won't be null
> >>>>     Iterator<Edge> iter = edges.iterator();
> >>>>     while (iter.hasNext()) {
> //iterate
> >>>> through all edges until we find agentB
> >>>>             Edge e = iter.next();
> >>>>             if (e.getOtherNode(agentA)==agentB) {  //use agentA as one
> >>>> node and see if the other node is agentB
> >>>>                 return true;
> >>>> //found it
> >>>>             }
> >>>>         }
> >>>>     return false; //did not find it
> >>>> }
> >>>>
> >>>> Then to achieve what you originally asked:
> >>>>
> >>>> if ( !areNeighbors(mynetwork, agentA,agentB)) {
> >>>>     mynetwork.addEdge(agentA,agentB,null);
> >>>> }
> >>>>
> >>>> Tony
> >>>>
> >>>>
> >>>>
> >>>> On Thu, Sep 26, 2013 at 3:54 AM, Beth Kar <[log in to unmask]> wrote:
> >>>>
> >>>>> Hello!
> >>>>> I am a newbie to mason (and java) and I am trying to dynamically
> create
> >>>>> an
> >>>>> undirected network. I want to add an edge between two nodes using the
> >>>>> following code:
> >>>>>
> >>>>> mynetwork.addEdge(AgentA, AgentB, null).
> >>>>>
> >>>>> How can I check with an if-then statement before hand if that edge
> >>>>> exists
> >>>>> before adding it?
> >>>>>
> >>>>> p.s. If ( edge between AgentA and AgentB doesn't exist) {
> >>>>> mynetwork.addEdge(AgentA, AgentB, null)}
> >>>>>
> >>>>> How do I represent the phrase 'edge between AgentA and AgentB doesn't
> >>>>> exist'
> >>>>> in java?
> >>>>>
> >>>>> Thank you in advance for your help!
> >>>>> Beth.
> >>>>>
> >>>>
> >>>>
> >>>
> >>
> >
>