my bad. The code snippet should be as follows:
for(UndirectedGraphNode node : UndirectedGraph.getNodesList() ) {
double sum = 0;
int count = 0;
for(UndirectedGraphNodeReference neighbor :
node.getNeighborsList() ) {
sum += ????
count++;
}
node.setWeight(sum/count);
}
----- graph.proto -----
package graph;
option java_package = "graph";
option java_outer_classname = "UndirectedGraphType";
option optimize_for = CODE_SIZE;
message UndirectedGraphNodeReference {
required string id = 1;
}
message UndirectedGraphNode {
required string id = 1;
required double weight = 2;
repeated UndirectedGraphNodeReference neighbors = 2;
}
message UndirectedGraph {
repeated UndirectedGraphNode nodes = 1;
}
On Oct 22, 2:36 pm, GDR <[EMAIL PROTECTED]> wrote:
> That does solve the duplicate information problem but it makes updates
> to node attributes (like weight) difficult. Let's say, I want to
> assign the weight of each node to the average of its neighbors.
>
> for(UndirectedGraphNode node : UndirectedGraph.getNodesList() ) {
> double sum = 0;
> int count = 0;
> for(UndirectedGraphNodeReference neighbor :
> node.getNeighborsList() ) {
> sum += ????
> count++;
> }
> node.setWeight(sum/count);
>
> }
>
> ----- graph.proto -----
>
> package graph;
>
> option java_package = "graph";
> option java_outer_classname = "UndirectedGraphType";
> option optimize_for = CODE_SIZE;
>
> message UndirectedGraphNodeReference {
> required string id = 1;
> required double weight = 2;
>
> }
>
> message UndirectedGraphNode {
> required string id = 1;
> repeated UndirectedGraphNodeReference neighbors = 2;
>
> }
>
> message UndirectedGraph {
> repeated UndirectedGraphNode nodes = 1;
>
> }
>
> On Oct 22, 2:14 pm, Jeremy Leader <[EMAIL PROTECTED]> wrote:
>
> > I was assuming all the properties of a node (weight, label, color,
> > whatever) would be in UndirectedGraphNode; UndirectedGraphNodeReference
> > would only have the id and nothing else.
>
> > --
> > Jeremy Leader
> > [EMAIL PROTECTED]
>
> > GDR wrote:
> > > Thanks Jeremy. That worked!
> > > But we now have information about the same node being replicated. For
> > > instance, let's say we have a field 'weight' attached to each node as
> > > shown below. This setup will replicate the weight information of a
> > > node as many times as its degree. If the weight of a node changes, I
> > > will have update all it's occurrences in the PB. Any way I can avoid
> > > it?
>
> > > package graph;
>
> > > option java_package = "graph";
> > > option java_outer_classname = "UndirectedGraphType";
> > > option optimize_for = CODE_SIZE;
>
> > > message UndirectedGraphNodeReference {
> > > required string id = 1;
> > > required double weight = 2;
> > > }
>
> > > message UndirectedGraphNode {
> > > required string id = 1;
> > > repeated UndirectedGraphNodeReference neighbors = 2;
> > > }
>
> > > message UndirectedGraph {
> > > repeated UndirectedGraphNode nodes = 1;
> > > }
>
> > > On Oct 21, 6:37 pm, Jeremy Leader <[EMAIL PROTECTED]> wrote:
> > >> Keep in mind that protobufs describe serialized data, and there's no
> > >> concept of an object reference like Java uses. In your example, if A
> > >> and B are neighbors, then in your proto, the data representing A
> > >> contains the data representing B, and the data representing B contains
> > >> the data representing A!
>
> > >> One way around this is to implement your own form of references, perhaps
> > >> using the node ids like this:
>
> > >> package graph;
>
> > >> option java_package = "graph";
> > >> option java_outer_classname = "UndirectedGraph";
> > >> option optimize_for = CODE_SIZE;
>
> > >> message UndirectedGraphNodeReference {
> > >> required string id = 0;
>
> > >> }
>
> > >> message UndirectedGraphNode {
> > >> required string id = 0;
> > >> repeated UndirectedGraphNodeReference neighbors;
>
> > >> }
>
> > >> message UndirectedGraph {
> > >> repeated UndirectedGraphNode nodes;
>
> > >> }
>
> > >> --
> > >> Jeremy Leader
> > >> [EMAIL PROTECTED]
>
> > >> GDR wrote:
> > >>> Hi,
> > >>> I'm wondering how would one go about implementing self-referential
> > >>> data structures? As an exercise, I tried to implement a PB version of
> > >>> the adjacency list representation of a graph. I'm having a hard time
> > >>> getting it work. Any suggestions?
> > >>> Thanks!
> > >>> --- graph.proto ---
> > >>> package graph;
> > >>> option java_package = "graph";
> > >>> option java_outer_classname = "UndirectedGraph";
> > >>> option optimize_for = CODE_SIZE;
> > >>> message UndirectedGraphNode {
> > >>> required string id = 0;
> > >>> repeated UndirectedGraphNode neighbors;
> > >>> }
> > >>> message UndirectedGraph {
> > >>> repeated UndirectedGraphNode nodes;
> > >>> }
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