/**
  *  Vertex update function.
  */
 void update(graphchi_vertex<VertexDataType, EdgeDataType> &vertex, graphchi_context &gcontext) {
     int ninedges = 0;
     if (gcontext.iteration == 0) {
         for(int i=0; i < vertex.num_inedges(); i++) {
             vertex.inedge(i)->set_data(vertex.id());        
             ninedges++;
         }
     } else {
         // Keep track of the number of edegs to ensure that
         // deletion works fine.
         if (vertex.get_data() != vertex.num_inedges())  {
             logstream(LOG_ERROR) << "Discrepancy in edge counts: " << vertex.get_data() << " != " << vertex.num_inedges() << std::endl;
         }
         assert(vertex.get_data() == vertex.num_inedges());
         
         for(int i=0; i < vertex.num_outedges(); i++) {
             graphchi_edge<vid_t> * edge = vertex.outedge(i);
             vid_t outedgedata = edge->get_data();
             vid_t expected = edge->vertex_id() + gcontext.iteration - (edge->vertex_id() > vertex.id());
             if (!is_deleted_edge_value(edge->get_data())) {
                 if (outedgedata != expected) {
                     logstream(LOG_ERROR) << outedgedata << " != " << expected << std::endl;
                     assert(false);
                 }
             }
         }
         for(int i=0; i < vertex.num_inedges(); i++) {
             vertex.inedge(i)->set_data(vertex.id() + gcontext.iteration);
             
             if (std::rand()  % 4 == 1) {
                 vertex.remove_inedge(i);
                 __sync_add_and_fetch(&ndeleted, 1);
             } else {
                 ninedges++;
             }
         }
     }
     
     if (gcontext.iteration == gcontext.num_iterations - 1) {
         vertex.set_data(gcontext.iteration + 1);
     } else {
         vertex.set_data(ninedges);
     }
 }
 /**
  *  Vertex update function.
  */
 void update(graphchi_vertex<VertexDataType, EdgeDataType> &vertex, graphchi_context &gcontext) {
     
     if (vertex.get_data().confirmed) {
         return;
     }
     
     VertexDataType vertexdata = vertex.get_data();
     bool propagate = false;
     if (gcontext.iteration == 0) {
         /* "Leader" of the SCC */
         if (vertexdata.color == vertex.id()) {
             propagate = true;
             vertex.remove_alloutedges();
         }
         
     } else {
         
         /* Loop over in-edges and see if there is a match */
         bool match = false;
         for(int i=0; i < vertex.num_outedges(); i++) {
             if (!vertex.outedge(i)->get_data().deleted()) {
                 if (vertex.outedge(i)->get_data().neighbor_label(vertex.id(), vertex.outedge(i)->vertexid) == vertexdata.color) {
                     match = true;
                     
                     break;
                 }
             }
         }
         if (match) {
             propagate = true;
             vertex.remove_alloutedges();
             vertex.set_data(SCCinfo(vertexdata.color, true));
         } else {
             vertex.set_data(SCCinfo(vertex.id(), false));
         }
     }
     
     
     if (propagate) {
         for(int i=0; i < vertex.num_inedges(); i++) {
             bidirectional_label edgedata = vertex.inedge(i)->get_data();
             if (!edgedata.deleted()) {
                 edgedata.my_label(vertex.id(), vertex.inedge(i)->vertexid) = vertexdata.color;
                 vertex.inedge(i)->set_data(edgedata);
                 gcontext.scheduler->add_task(vertex.inedge(i)->vertexid, true);
             }
         }
     }
 }
Example #3
0
	void update(graphchi_vertex<VertexDataType, EdgeDataType> &vertex, graphchi_context &gcontext) {
		
		assert(vertex.num_inedges() * vertex.num_outedges() <= product);

		for(int i=0; i<vertex.num_outedges(); i++){
			bidirectional_label edgedata = vertex.outedge(i)->get_data();
			if(edgedata.is_equal()){		
				if(root == edgedata.my_label(vertex.id(), vertex.outedge(i)->vertexid)){
					lock.lock();
						fprintf(fpout, "%u\t%u\n", vertex.id(), vertex.outedge(i)->vertexid);
					lock.unlock();
					continue;
				}
			}
			lock.lock();
			fprintf(fpout1, "%u\t%u\n", vertex.id(), vertex.outedge(i)->vertexid);
			lock.unlock();
		}
	}
Example #4
0
  /**
   *  Vertex update function.
   */
  void update(graphchi_vertex<VertexDataType, EdgeDataType> &vertex, graphchi_context &gcontext) {
    //go over all user nodes
    if ( vertex.num_outedges() > 0 && (algo == GLOBAL_MEAN || algo == USER_MEAN)){
      vertex_data & user = latent_factors_inmem[vertex.id()]; 

      //go over all ratings
      if (algo == USER_MEAN){
        for(int e=0; e < vertex.num_edges(); e++) {
          float observation = vertex.edge(e)->get_data();                
          user.mean_rating += observation;
        }
        if (vertex.num_edges() > 0)
          user.mean_rating /= vertex.num_edges();
      }

      //go over all ratings
      for(int e=0; e < vertex.num_edges(); e++) {
        double prediction;
        float observation = vertex.edge(e)->get_data();                
        vertex_data & movie = latent_factors_inmem[vertex.edge(e)->vertex_id()];
        rmse_vec[omp_get_thread_num()] += baseline_predict(user, movie, observation, prediction);
      }
    }
    else if (vertex.num_inedges() > 0 && algo == ITEM_MEAN){
      vertex_data & user = latent_factors_inmem[vertex.id()]; 

      //go over all ratings
      for(int e=0; e < vertex.num_edges(); e++) {
        float observation = vertex.edge(e)->get_data();                
        user.mean_rating += observation;
      } 
      if (vertex.num_edges() > 0)
        user.mean_rating /= vertex.num_edges();

      for(int e=0; e < vertex.num_edges(); e++) {
        float observation = vertex.edge(e)->get_data();                
        double prediction;
        vertex_data & movie = latent_factors_inmem[vertex.edge(e)->vertex_id()];
        rmse_vec[omp_get_thread_num()] += baseline_predict(movie, user, observation, prediction);
      }
    }
  }
Example #5
0
 /**
   * Pagerank update function.
   */
 void update(graphchi_vertex<VertexDataType, EdgeDataType> &v, graphchi_context &ginfo) {
     float sum=0;
     if (ginfo.iteration == 0) {
         /* On first iteration, initialize vertex and out-edges. 
            The initialization is important,
            because on every run, GraphChi will modify the data in the edges on disk. 
          */
         for(int i=0; i < v.num_outedges(); i++) {
             graphchi_edge<float> * edge = v.outedge(i);
             edge->set_data(1.0 / v.num_outedges());
         }
         v.set_data(RANDOMRESETPROB); 
     } else {
         /* Compute the sum of neighbors' weighted pageranks by
            reading from the in-edges. */
         for(int i=0; i < v.num_inedges(); i++) {
             float val = v.inedge(i)->get_data();
             sum += val;                    
         }
         
         /* Compute my pagerank */
         float pagerank = RANDOMRESETPROB + (1 - RANDOMRESETPROB) * sum;
         
         /* Write my pagerank divided by the number of out-edges to
            each of my out-edges. */
         if (v.num_outedges() > 0) {
             float pagerankcont = pagerank / v.num_outedges();
             for(int i=0; i < v.num_outedges(); i++) {
                 graphchi_edge<float> * edge = v.outedge(i);
                 edge->set_data(pagerankcont);
             }
         }
             
         /* Keep track of the progression of the computation.
            GraphChi engine writes a file filename.deltalog. */
         ginfo.log_change(std::abs(pagerank - v.get_data()));
         
         /* Set my new pagerank as the vertex value */
         v.set_data(pagerank); 
     }
 }
 void update(graphchi_vertex<VertexDataType, EdgeDataType>& v, graphchi_context& ginfo)
 {
     if (ginfo.iteration > 0) {
         float sum = 0;
         for (int i = 0; i < v.num_inedges(); i++) {
             sum += pr[v.inedge(i)->vertexid];
         }
         if (v.outc > 0) {
             pr[v.id()] = (RANDOMRESETPROB + (1 - RANDOMRESETPROB) * sum) / v.outc;
         } else {
             pr[v.id()] = (RANDOMRESETPROB + (1 - RANDOMRESETPROB) * sum);
         }
     } else if (ginfo.iteration == 0) {
         if (v.outc > 0)
             pr[v.id()] = 1.0f / v.outc;
     }
     if (ginfo.iteration == ginfo.num_iterations - 1) {
         /* On last iteration, multiply pr by degree and store the result */
         v.set_data(v.outc > 0 ? pr[v.id()] * v.outc : pr[v.id()]);
     }
 }
    /**
      * Pagerank update function.
      */
    void update(graphchi_vertex<VertexDataType, EdgeDataType> &v, graphchi_context &ginfo) {
        float sum=0;
	float prv = 0.0;
	float pagerankcont = 0.0;	

        if (ginfo.iteration == 0) {
            /* On first iteration, initialize vertex and out-edges. 
               The initialization is important,
               because on every run, GraphChi will modify the data in the edges on disk. 
             */
	    /* For the weighted version */
	    update_edge_data(v, 1.0, true);
            v.set_data(RANDOMRESETPROB); 
            //v.set_data(1.0); 
        } else {
	    /* We need to come up with the weighted version */
            for(int i=0; i < v.num_inedges(); i++) {
                chivector<float> * evector = v.inedge(i)->get_vector();
                assert(evector->size() >= 2);
                sum += evector->get(1);
    		//std::cout <<  v.id() << " with data: " << evector->get(1) << " with weight " << evector->get(0) << std::endl;
    		//std::cout <<  v.id() << " edge endpoint: " << v.inedge(i)->vertex_id() << std::endl;
		//evector->clear();
	    }

            /* Compute my pagerank */
            prv = RANDOMRESETPROB + (1 - RANDOMRESETPROB) * sum;
	    //std::cout << "sum" << sum << "pagerank: " << prv << std::endl;

	    update_edge_data(v, prv, false);
            /* Keep track of the progression of the computation.
               GraphChi engine writes a file filename.deltalog. */
	    double delta = std::abs(prv - v.get_data());
	    //std::cout << "pagerank: " << prv << "v.data" << v.get_data() << "delta: " << delta << std::endl;
            ginfo.log_change(delta);
            
            /* Set my new pagerank as the vertex value */
            v.set_data(prv);
        }
    }
Example #8
0
    /**
     *  Vertex update function.
     */
    void update(graphchi_vertex<VertexDataType, EdgeDataType> &vertex, graphchi_context &gcontext) {


        if (gcontext.iteration == 0) {
            if (is_user(vertex.id()) && vertex.num_outedges() > 0) {
                vertex_data& user = latent_factors_inmem[vertex.id()];
                user.pvec = zeros(D*3);
                for(int e=0; e < vertex.num_outedges(); e++) {
                    rbm_movie mov = latent_factors_inmem[vertex.edge(e)->vertex_id()];
                    float observation = vertex.edge(e)->get_data();
                    int r = (int)(observation/rbm_scaling);
                    assert(r < rbm_bins);
                    mov.bi[r]++;
                }
            }
            return;
        } else if (gcontext.iteration == 1) {
            if (vertex.num_inedges() > 0) {
                rbm_movie mov = latent_factors_inmem[vertex.id()];
                setRand2(mov.w, D*rbm_bins, 0.001);
                for(int r = 0; r < rbm_bins; ++r) {
                    mov.bi[r] /= (double)vertex.num_inedges();
                    mov.bi[r] = log(1E-9 + mov.bi[r]);

                    if (mov.bi[r] > 1000) {
                        assert(false);
                        Rcpp::Rcerr<<"Numerical overflow" <<std::endl;
                    }
                }
            }

            return; //done with initialization
        }
        //go over all user nodes
        if (is_user(vertex.id()) && vertex.num_outedges()) {
            vertex_data & user = latent_factors_inmem[vertex.id()];
            user.pvec = zeros(3*D);
            rbm_user usr(user);

            vec v1 = zeros(vertex.num_outedges());
            //go over all ratings
            for(int e=0; e < vertex.num_outedges(); e++) {
                float observation = vertex.edge(e)->get_data();
                rbm_movie mov = latent_factors_inmem[vertex.edge(e)->vertex_id()];
                int r = (int)(observation / rbm_scaling);
                assert(r < rbm_bins);
                for(int k=0; k < D; k++) {
                    usr.h[k] += mov.w[D*r + k];
                    assert(!std::isnan(usr.h[k]));
                }
            }

            for(int k=0; k < D; k++) {
                usr.h[k] = sigmoid(usr.h[k]);
                if (drand48() < usr.h[k])
                    usr.h0[k] = 1;
                else usr.h0[k] = 0;
            }


            int i = 0;
            double prediction;
            for(int e=0; e < vertex.num_outedges(); e++) {
                rbm_movie mov = latent_factors_inmem[vertex.edge(e)->vertex_id()];
                float observation = vertex.edge(e)->get_data();
                predict1(usr, mov, observation, prediction);
                int vi = (int)(prediction / rbm_scaling);
                v1[i] = vi;
                i++;
            }

            i = 0;
            for(int e=0; e < vertex.num_outedges(); e++) {
                rbm_movie mov = latent_factors_inmem[vertex.edge(e)->vertex_id()];
                int r = (int)v1[i];
                for (int k=0; k< D; k++) {
                    usr.h1[k] += mov.w[r*D+k];
                }
                i++;
            }

            for (int k=0; k < D; k++) {
                usr.h1[k] = sigmoid(usr.h1[k]);
                if (drand48() < usr.h1[k])
                    usr.h1[k] = 1;
                else usr.h1[k] = 0;
            }

            i = 0;
            for(int e=0; e < vertex.num_outedges(); e++) {
                rbm_movie mov = latent_factors_inmem[vertex.edge(e)->vertex_id()];
                float observation = vertex.edge(e)->get_data();
                double prediction;
                rbm_predict(user, mov, observation, prediction, NULL);
                double pui = prediction / rbm_scaling;
                double rui = observation / rbm_scaling;
                rmse_vec[omp_get_thread_num()] += (pui - rui) * (pui - rui);
                //nn += 1.0;
                int vi0 = (int)(rui);
                int vi1 = (int)v1[i];
                for (int k = 0; k < D; k++) {
                    mov.w[D*vi0+k] += rbm_alpha * (usr.h0[k] - rbm_beta * mov.w[vi0*D+k]);
                    assert(!std::isnan(mov.w[D*vi0+k]));
                    mov.w[D*vi1+k] -= rbm_alpha * (usr.h1[k] + rbm_beta * mov.w[vi1*D+k]);
                    assert(!std::isnan(mov.w[D*vi1+k]));
                }
                i++;
            }
        }
    }
Example #9
0
    /**
     *  Vertex update function.
     */
    void update(graphchi_vertex<VertexDataType, EdgeDataType> &vertex, graphchi_context &gcontext) {
              
		VertexDataType vertexdata; //= vertex.get_data();
		//bool propagate = false;
		if (gcontext.iteration == 0) {
			//vertex.set_data(SCCinfo(vertex.id()));
			vertexdata = vertex.get_data();
			/* vertices that is not visited in Fw phase is not in the giant SCC!
			 * minor improve by mzj 2016/3/13
			 */
			if(!vertexdata.confirmed)
				return;
			//assert(vertexdata.color == root);
			if(vertex.id() == root){
				//vertexdata.confirmed = true;
				vertexdata.color = vertex.id(); 
				vertexdata.reconfirmed = true; 
				for(int i=0; i<vertex.num_inedges(); i++){
					bidirectional_label edgedata = vertex.inedge(i)->get_data();
					edgedata.my_label(vertex.id(), vertex.inedge(i)->vertexid) = vertex.id();
					vertex.inedge(i)->set_data(edgedata);
					if(scheduler) gcontext.scheduler->add_task(vertex.inedge(i)->vertexid);	
					vertex.inedge(i)->set_data(edgedata);
				}	
				vertex.set_data(vertexdata);	
			}else{
				vertexdata.reconfirmed = false;
				vertexdata.color = vertex.id(); 
				for(int i=0; i<vertex.num_inedges(); i++){
					bidirectional_label edgedata = vertex.inedge(i)->get_data();
					edgedata.my_label(vertex.id(), vertex.inedge(i)->vertexid) = vertex.id();
					vertex.inedge(i)->set_data(edgedata);
					//if(scheduler) gcontext.scheduler->add_task(vertex.outedge(i)->vertexid);	
				}	
				vertex.set_data(vertexdata);	
			}
			//vertex.set_data(vertexdata);	
		} else {
			vertexdata = vertex.get_data();
			if(!vertexdata.confirmed)
				return ;
			vid_t min_color = vertexdata.color;
			for(int i=0; i<vertex.num_outedges(); i++){
				//min_color = std::min(min_color, vertexdata.inedge(i)->get_data().neighbor_label(vertex.id(), vertex.inedge(i)->vertexid));		
				if(root == (vertex.outedge(i)->get_data()).neighbor_label(vertex.id(), vertex.outedge(i)->vertexid)){
						min_color = root;
						break;
				}
			}
			if(min_color != vertexdata.color){
				converged = false;
				//vertexdata.confirmed = true;
				vertexdata.reconfirmed = true;
				vertexdata.color = min_color;
				for(int i=0; i<vertex.num_inedges(); i++){
					bidirectional_label edgedata = vertex.inedge(i)->get_data();
					edgedata.my_label(vertex.id(), vertex.inedge(i)->vertexid) = min_color;
					if(scheduler) gcontext.scheduler->add_task(vertex.inedge(i)->vertexid);	
					vertex.inedge(i)->set_data(edgedata);
				}	
				vertex.set_data(vertexdata);
			}
		}
    }
Example #10
0
    /**
     *  Vertex update function.
     */
	void update(graphchi_vertex<VertexDataType, EdgeDataType> &vertex, graphchi_context &gcontext) {

		VertexDataType vertexdata; //= vertex.get_data();
		bool propagate = false;
		if (gcontext.iteration == 0) {

			//vertex.set_data(SCCinfo(vertex.id()));
			vertexdata = vertex.get_data();
			vertexdata.color = vertex.id();
			

			if(vertex.id() == root){
				product = vertex.num_inedges() * vertex.num_outedges(); 

				vertexdata.confirmed = true;
				vertex.set_data(vertexdata);
				for(int i=0; i<vertex.num_outedges(); i++){
					bidirectional_label edgedata = vertex.outedge(i)->get_data();
					edgedata.my_label(vertex.id(), vertex.outedge(i)->vertexid) = vertex.id();
					if(scheduler) gcontext.scheduler->add_task(vertex.outedge(i)->vertexid);	
					vertex.outedge(i)->set_data(edgedata);
				}	
			}else{
				vertexdata.confirmed = false;
				vertex.set_data(vertexdata);
				for(int i=0; i<vertex.num_outedges(); i++){
					bidirectional_label edgedata = vertex.outedge(i)->get_data();
					edgedata.my_label(vertex.id(), vertex.outedge(i)->vertexid) = vertex.id();
					//if(scheduler) gcontext.scheduler->add_task(vertex.outedge(i)->vertexid);	
					vertex.outedge(i)->set_data(edgedata);
				}	
				// initialize labels on in and out edges
				for(int i=0; i<vertex.num_inedges(); i++){
					bidirectional_label edgedata = vertex.inedge(i)->get_data();
					edgedata.my_label(vertex.id(), vertex.inedge(i)->vertexid) = vertex.id();
					//if(scheduler) gcontext.scheduler->add_task(vertex.outedge(i)->vertexid);	
					vertex.inedge(i)->set_data(edgedata);
				}	
			}
		} else {
			if(true == vertexdata.confirmed)
				return ;
			vertexdata = vertex.get_data();
			vid_t min_color = vertexdata.color;
			for(int i=0; i<vertex.num_inedges(); i++){
				//min_color = std::min(min_color, vertexdata.inedge(i)->get_data().neighbor_label(vertex.id(), vertex.inedge(i)->vertexid));		
				if(root == (vertex.inedge(i)->get_data()).neighbor_label(vertex.id(), vertex.inedge(i)->vertexid)){
						min_color = root;
						break;
				}
			}
			if(min_color != vertexdata.color){
				converged = false;
				vertexdata.confirmed = true;
				vertexdata.color = min_color;
				for(int i=0; i<vertex.num_outedges(); i++){
					bidirectional_label edgedata = vertex.outedge(i)->get_data();
					edgedata.my_label(vertex.id(), vertex.outedge(i)->vertexid) = min_color;
					if(scheduler) gcontext.scheduler->add_task(vertex.outedge(i)->vertexid);	
					vertex.outedge(i)->set_data(edgedata);
				}	
				vertex.set_data(vertexdata);
			}
		}
	}
 /**
  *  Vertex update function.
  */
 void update(graphchi_vertex<VertexDataType, EdgeDataType> &vertex, graphchi_context &gcontext) {
     if (first_iteration) {
         vertex.set_data(SCCinfo(vertex.id()));
     }
    
     
     if (vertex.get_data().confirmed) {
        
         if (vertex.num_edges() > 0) {
             vertex.remove_alledges();
         }
         return;
     }
     
     /* Vertices with only in or out edges cannot be part of a SCC (Trimming) */
     if (vertex.num_inedges() == 0 || vertex.num_outedges() == 0) {
         if (vertex.num_edges() > 0) {
             // TODO: check this logic!
             vertex.set_data(SCCinfo(vertex.id(), true));
         }
         vertex.remove_alledges();
         return;
     }
     remainingvertices = true;
     
     VertexDataType vertexdata = vertex.get_data();
     bool propagate = false;
     if (gcontext.iteration == 0) {
         vertexdata = vertex.id();
         propagate = true;
         /* Clean up in-edges. This would be nicer in the messaging abstraction... */
         for(int i=0; i < vertex.num_inedges(); i++) {
             bidirectional_label edgedata = vertex.inedge(i)->get_data();
             if (!edgedata.deleted()) {
                 edgedata.my_label(vertex.id(), vertex.inedge(i)->vertexid) = vertex.id();
                 vertex.inedge(i)->set_data(edgedata);
             }
         }
     } else {
         
         /* Loop over in-edges and choose minimum color */
         vid_t minid = vertexdata.color;
         for(int i=0; i < vertex.num_inedges(); i++) {
             if (!vertex.inedge(i)->get_data().deleted()) {
                 minid = std::min(minid, vertex.inedge(i)->get_data().neighbor_label(vertex.id(), vertex.inedge(i)->vertexid));
             }
         }
         
         if (minid != vertexdata.color) {
             vertexdata.color = minid;
             propagate = true;
         }
     }
     vertex.set_data(vertexdata);
     
     if (propagate) {
         for(int i=0; i < vertex.num_outedges(); i++) {
             bidirectional_label edgedata = vertex.outedge(i)->get_data();
             if (!edgedata.deleted()) {
                 edgedata.my_label(vertex.id(), vertex.outedge(i)->vertexid) = vertexdata.color;
                 vertex.outedge(i)->set_data(edgedata);
                 gcontext.scheduler->add_task(vertex.outedge(i)->vertexid, true);
             }
         }
     }
 }
    void update(graphchi_vertex<VertexDataType, EdgeDataType> &vertex, graphchi_context &gcontext) {


        //For iteration 0
        if (gcontext.iteration == 0) {
            
           
            chivector<vid_t> * v_vector = vertex.get_vector();
            v_vector->clear();
            
            /* Initialize a json object, rvec to maintain the result vector of the current node.
             * Maintain the list of outedges of the current vector. 
             * These outedges are the children and must match the children of the query node.
             * Maintain a vector for all the nodes set to false in the current iteraion. 
             */
            nlohmann::json rvec;
            std::vector<vid_t> vertex_outedges;
            std::vector<vid_t> vertex_false;
            
            for (int i = 0; i < vertex.num_outedges(); i++) {
                vertex_outedges.push_back(vertex.outedge(i)->vertex_id());
            }
            
            /*
             * Iterate through all the query nodes, and check the equality with the current node. 
             * If the current node matches the query node, add the dependencies of the query node to the rvec.
             * If the query node does not have any dependencies, set rvec[i] as true. (This implies a direct match)
             * If the query node and the current node don't match, set rvec[i] to false and add i to vertex_false.
             */
            for(unsigned int i=0; i < query_json["node"].size(); i++) {
                if(check_equal(vertex_json[vertex.id()],query_json["node"][i])) {    
                    unsigned int out_d = query_json["node"][i]["out_degree"];
                    if(out_d == 0){
                        rvec[i] = true;
                        v_vector->add(i);
                    }
                    else if(vertex_outedges.size() == 0)
                    {
                        rvec[i] = false;
                        vertex_false.push_back(i);
                    }
                    else
                    {    for(unsigned int j=0; j <query_json["edge"].size(); j++){
                            unsigned int source = query_json["edge"][j]["source"], target = query_json["edge"][j]["target"];
                            if(i == source )
                                rvec[i][target] = vertex_outedges;
                        }
                        v_vector->add(i);
                    }
                    
                }
                else
                {
                    rvec[i] = false;
                    vertex_false.push_back(i);
                }
            }
            
            // Access the element of rvec_map with key equal to current vertex id. 
            // Assign rvec as the value for current vertex id.
            tbb::concurrent_hash_map<unsigned int, nlohmann::json>::accessor ac;
            rvec_map.insert(ac,vertex.id());
            ac->second = rvec;
            ac.release();
            
            /*
             * If the size of vertex_false is not zero, changes have been made in the current iteration.
             * For all the inedges, add the all the elements of vertex_false to the edge vector.
             * Schedule all the inedges for the next iteration.
             * 
             */
            
            if(vertex_false.size() != 0) {
                for(int i = 0; i < vertex.num_inedges(); i++) {
                    chivector<vid_t> * e_vector = vertex.inedge(i)->get_vector();
                    e_vector->clear();
                    for(unsigned int j = 0; j< vertex_false.size(); j++){
                        e_vector->add(vertex_false[j]);
                    }
                    gcontext.scheduler->add_task(vertex.inedge(i)->vertex_id());
                }
            }    

        } 
        
        //For iteration 1..n
        else{
            
            /*
             * Retrieve the rvec for the current node from the rvec_map. 
             * Intialize vertex_false to maintain the vertices set to false.  
             */
            tbb::concurrent_hash_map<unsigned int, nlohmann::json>::accessor ac;
            rvec_map.find(ac,vertex.id());
            nlohmann::json rvec = ac->second;
            std::vector<vid_t> vertex_false;
            
            chivector<vid_t> * v_vector = vertex.get_vector();
            
                    
            
            /*
             * Iterate through all the outedges.
             * Iterate through each edge vector (e_vector).
             * Get the target value, t from each element in the edge vector.
             * If rvec[k] isn't a bool and rvec[k] has dependencies on t, remove j from rvec[k][t].
             * If rvec[k][t] is now empty, set rvec[k] = false and add it to vertex_false.
             * Else update rvec[k][t].
             */
            for(int i = 0; i < vertex.num_outedges(); i++){

                chivector<vid_t> * e_vector = vertex.outedge(i)->get_vector();
                if(e_vector->size() != 0 ) {
                    for(unsigned int j =0; j < e_vector->size(); j++){
                        vid_t t = e_vector->get(j);
                        for(unsigned int k = 0; k < rvec.size(); k++ ) {
                            
                            if(rvec[k].is_boolean())
                                continue;
                            if(rvec[k][t].is_null())
                                continue;
                            
                            std::vector <vid_t> desc(rvec[k][t].begin(),rvec[k][t].end());
                            
                            std::vector <vid_t>::iterator it = std::find(desc.begin(), desc.end(), vertex.outedge(i)->vertex_id());
                            if(it != desc.end())
                            {
                                desc.erase(it);
                                if(desc.size() == 0){
                                    rvec[k] = false;
                                    vertex_false.push_back(k);
                                }
                                else
                                    rvec[k][t] = desc;
                            }                                
                        }
                    }
                }
                e_vector->clear();
            }
            
            /*
             * If the size of vertex_false is not zero, changes have been made in the current iteration.
             * Update the vertex vector.
             * For all the inedges, add the all the elements of vertex_false to the edge vector.
             * Schedule all the inedges for the next iteration.
             */
           
            
            
            if(vertex_false.size() != 0){
            //Update the new match nodes for the vertex by adding only the current matches to the vertex vector.
                v_vector->clear();
                for(unsigned int i = 0; i < rvec.size(); i++){
                    if(!rvec[i].is_boolean()) 
                        v_vector->add(i);
                    else if(rvec[i])
                        v_vector->add(i);
                }
                for(int i=0; i < vertex.num_inedges(); i++){
                   chivector<vid_t> * e_vector = vertex.inedge(i) -> get_vector();
                    for(unsigned int j = 0; j < vertex_false.size(); j++)
                        e_vector->add(vertex_false[j]);
                    gcontext.scheduler->add_task(vertex.inedge(i)->vertex_id());
                }
            }
            ac -> second = rvec;
            ac.release();
        }

    }
    void update(graphchi_vertex<VertexDataType, EdgeDataType> &vertex, graphchi_context &gcontext) {
            
        /*
         * Concurrent accessor to access the rvec value corresponding to the current vertex.
         */
         
        tbb::concurrent_hash_map<unsigned int, nlohmann::json>::accessor ac;
        rvec_map.insert(ac,vertex.id());
        nlohmann::json rvec = ac->second;
        
        int dependencies; //The number of active dependencies of the current vertex. 
        
        /*
         * vertex_false to keep track of all the query vertices marked false for the vertex in the current iteration
         */

        std::vector<vid_t> vertex_false;

        

        /*
         * If the vertex has a null rvec, it is being computed for the first time. 
         * Compare the vertex with each of the vertices in the query graph.
         * If the current node matches the query node, add the dependencies of the query node to the rvec.
         * If the query node does not have any dependencies, set rvec[i] as true. (This implies a direct match)
         * If the query node and the current node don't match, set rvec[i] to false and add i to vertex_false. 
         */
        
        if(rvec.is_null()){
           
            dependencies = 0; //Vertex is being computed for the first time and hence has zero dependencies. 
            
            for(unsigned int i=0; i < query_json["node"].size(); i++) {
                if(check_equal(vertex_json[vertex.id()],query_json["node"][i])) {    
                    unsigned int out_d = query_json["node"][i]["out_degree"];
                    if(out_d == 0){
                        rvec[i] = true;
                    }
                    else if(vertex.num_outedges() == 0)
                    {
                        rvec[i] = false;
                        vertex_false.push_back(i);
                    }
                    else
                    {   for(unsigned int j=0; j <query_json["edge"].size(); j++){
                            unsigned int source = query_json["edge"][j]["source"], target = query_json["edge"][j]["target"];
                            if(i == source )
                                rvec[i][target] = vertex.num_outedges();
                        }
                        dependencies++;
                    }

                }
                else
                {
                    rvec[i] = false;
                    vertex_false.push_back(i);
                }
            }
            /*
             * If the vertex has dependencies, schedule the children of the current vertex (outedges).
             */
            if(dependencies != 0){
                for(int i = 0; i <vertex.num_outedges();i++)
                    gcontext.scheduler->add_task(vertex.outedge(i)->vertex_id());
            }
            
            /*
             * Vertex data is set to the number of dependencies.
             * If the vertex data is greater than 0, then it is processed whenever it is scheduled in the subsequent iterations.
             * If the vertex data is 0, it is not processed in the subsequent iterations.  
             */
            vertex.set_data(dependencies);
        } 
            
        dependencies = vertex.get_data();
        
        /*
         * If the current vertex has dependencies, it has to be processed.
         * Collect the edge data of all it's outgoing edges and for each outgoing edge which is updated, update the corresponding dependency.
         * Else, clear all the outedges. 
         */
        
        if(dependencies != 0 ) {
            
            nlohmann::json updates;
            
            for(int i = 0; i < vertex.num_outedges(); i++){
                chivector<vid_t> * e_vector = vertex.outedge(i)->get_vector();
                int evector_size = e_vector->size();
                for( int j =0; j < evector_size; j++){
                    vid_t t = e_vector->get(j);
                    if(updates[t].is_null())
                        updates[t] = 1;
                    else {
                        int n = updates[t];
                        updates[t] = n +1;
                    }
                }
                e_vector->clear();
            }
            
            for(vid_t i = 0; i < updates.size(); i++ ) {
                if(updates[i].is_null())
                    continue;
                int cur_updates = updates[i];
                for(size_t j = 0; j < rvec.size(); j++){
                    if(rvec[j].is_boolean())
                        continue;
                    if(rvec[j][i].is_number()){
                        int prev_dep = rvec[j][i];
                        if(prev_dep <= cur_updates) {
                            rvec[j] = false;
                            vertex_false.push_back(j);
                            dependencies --;
                        }
                        else
                            rvec[j][i] = prev_dep - cur_updates;
                    }
                }
            }
            vertex.set_data(dependencies);
        } else {
            for(int i = 0; i < vertex.num_outedges(); i++){
                chivector<vid_t> * e_vector = vertex.outedge(i)->get_vector();
                if(e_vector->size())
                    e_vector ->clear();
            }
        }
   
        /*
         * If a node has been set to false in the current iteration, propagate the update through all the inedges.
         */
        if(vertex_false.size() != 0){
            for(int i=0; i < vertex.num_inedges(); i++){
                chivector<vid_t> * e_vector = vertex.inedge(i) -> get_vector();
                 for(unsigned int j = 0; j < vertex_false.size(); j++)
                     e_vector->add(vertex_false[j]);
                 gcontext.scheduler->add_task(vertex.inedge(i)->vertex_id());
            }
        }
        
        // Update the result vector and release the accsessor. 
        ac->second = rvec;
        ac.release();

    }