public static void Triangles(this PINQCollection <Pair <int> > graph, Pair <int>[] buckets, double epsilon)
{
var symmGraph = graph.Select(edge => new Pair <int>(edge.b, edge.a));
var undirectedGraph = graph.Concat(symmGraph);
var abc = undirectedGraph.Join(undirectedGraph, x => x.b, y => y.a, (x, y) => new Triple(x.a, x.b, y.b));
var bca = abc.Select(x => new Triple(x.b, x.c, x.a));
var cab = abc.Select(x => new Triple(x.c, x.a, x.b));
var result = abc.Intersect(bca).Intersect(cab);
Console.WriteLine("triangles: {0}", result.Count(x => true, epsilon)[true]);
}
public static PINQCollection <Triple> jddTriangles(this PINQCollection <Pair <int> > graph, Pair <int>[] buckets, double epsilon)
{
bool symmetry = false;
if (symmetry)
{
var symmGraph = graph.Select(edge => new Pair <int>(edge.b, edge.a));
var undirectedGraph = graph.Concat(symmGraph);
graph = undirectedGraph;
//I need to double the buckets (maybe is not correct to double)
for (int i = 0; i < buckets.Length; i++)
{
buckets[i].a = buckets[i].a * 2;
buckets[i].b = buckets[i].b * 2;
}
}
// does a DPCount, but then immediately replaces the degree with the bucket.
//var aBuckets = graph.DPCount(x => x.a, (k, i) => new Pair<int>(k, buckets.Where(bucket => i < bucket.a).First().a));
//var bBuckets = graph.DPCount(x => x.b, (k, i) => new Pair<int>(k, buckets.Where(bucket => i < bucket.b).First().b));
//var aDegEdge = graph.Join(aBuckets, edge => edge.a, pair => pair.a, (edge, pair) => new Pair<Pair<int>, int>(edge, pair.b));
//var bDegEdge = graph.Join(bBuckets, edge => edge.b, pair => pair.a, (edge, pair) => new Pair<Pair<int>, int>(edge, pair.b));
var aDegrees = graph.DPCount(x => x.a, (k, i) => new Pair <int>(k, i));
var bDegrees = graph.DPCount(x => x.b, (k, i) => new Pair <int>(k, i));
var aDegEdge = graph.Join(aDegrees, edge => edge.a, pair => pair.a, (edge, pair) => new Pair <Pair <int>, int>(edge, pair.b));
var bDegEdge = graph.Join(bDegrees, edge => edge.b, pair => pair.a, (edge, pair) => new Pair <Pair <int>, int>(edge, pair.b));
var edgeDegree = aDegEdge.Join(bDegEdge, aTriple => aTriple.a, bTriple => bTriple.a, (aTriple, bTriple)
=> new Triple <Pair <int>, int, int>(aTriple.a, aTriple.b, bTriple.b));
//create a a path of length 3 with the degrees of each node involved
var abc = edgeDegree.Join(edgeDegree, x => x.a.b, y => y.a.a, (x, y) => new Triple(x.b, x.c, y.c));
return(abc);
}
