GraphLite图计算PageRank

/** * @file PageRankVertex.cc * @author  Songjie Niu, Shimin Chen * @version 0.1 * * @section LICENSE  *  * Copyright 2016 Shimin Chen ([e-mail]) and * Songjie Niu ([e-mail]) *  * Licensed under the Apache License, Version 2.0 (the "License"); * you may not use this file except in compliance with the License. * You may obtain a copy of the License at * *     http://www.apache.org/licenses/LICENSE-2.0 * * Unless required by applicable law or agreed to in writing, software * distributed under the License is distributed on an "AS IS" BASIS, * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. * See the License for the specific language governing permissions and * limitations under the License. *  * @section DESCRIPTION *  * This file implements the PageRank algorithm using graphlite API. * */#include <stdio.h>#include <string.h>#include <math.h>#include "GraphLite.h"#define VERTEX_CLASS_NAME(name) PageRankVertex##name#define EPS 1e-6class VERTEX_CLASS_NAME(InputFormatter): public InputFormatter {public:    int64_t getVertexNum() {        unsigned long long n;        sscanf(m_ptotal_vertex_line, "%lld", &n);        m_total_vertex= n;        return m_total_vertex;    }    int64_t getEdgeNum() {        unsigned long long n;        sscanf(m_ptotal_edge_line, "%lld", &n);        m_total_edge= n;        return m_total_edge;    }    int getVertexValueSize() {        m_n_value_size = sizeof(double);        return m_n_value_size;    }    int getEdgeValueSize() {        m_e_value_size = sizeof(double);        return m_e_value_size;    }    int getMessageValueSize() {        m_m_value_size = sizeof(double);        return m_m_value_size;    }    void loadGraph() {        unsigned long long last_vertex;        unsigned long long from;        unsigned long long to;        double weight = 0;                double value = 1;        int outdegree = 0;                const char *line= getEdgeLine();        // Note: modify this if an edge weight is to be read        //       modify the 'weight' variable        sscanf(line, "%lld %lld", &from, &to);        addEdge(from, to, &weight);        last_vertex = from;        ++outdegree;        for (int64_t i = 1; i < m_total_edge; ++i) {            line= getEdgeLine();            // Note: modify this if an edge weight is to be read            //       modify the 'weight' variable            sscanf(line, "%lld %lld", &from, &to);            if (last_vertex != from) {                addVertex(last_vertex, &value, outdegree);                last_vertex = from;                outdegree = 1;            } else {                ++outdegree;            }            addEdge(from, to, &weight);        }        addVertex(last_vertex, &value, outdegree);    }};class VERTEX_CLASS_NAME(OutputFormatter): public OutputFormatter {public:    void writeResult() {        int64_t vid;        double value;        char s[1024];        for (ResultIterator r_iter; ! r_iter.done(); r_iter.next() ) {            r_iter.getIdValue(vid, &value);            int n = sprintf(s, "%lld: %f\n", (unsigned long long)vid, value);            writeNextResLine(s, n);        }    }};// An aggregator that records a double value tom compute sumclass VERTEX_CLASS_NAME(Aggregator): public Aggregator<double> {public:    void init() {        m_global = 0;        m_local = 0;    }    void* getGlobal() {        return &m_global;    }    void setGlobal(const void* p) {        m_global = * (double *)p;    }    void* getLocal() {        return &m_local;    }    void merge(const void* p) {        m_global += * (double *)p;    }    void accumulate(const void* p) {        m_local += * (double *)p;    }};class VERTEX_CLASS_NAME(): public Vertex <double, double, double> {public:    void compute(MessageIterator* pmsgs) {        double val;        if (getSuperstep() == 0) {           val= 1.0;        } else {            if (getSuperstep() >= 2) {                double global_val = * (double *)getAggrGlobal(0);                if (global_val < EPS) {                    voteToHalt(); return;                }            }            double sum = 0;            for ( ; ! pmsgs->done(); pmsgs->next() ) {                sum += pmsgs->getValue();            }            val = 0.15 + 0.85 * sum;            double acc = fabs(getValue() - val);            accumulateAggr(0, &acc);        }        * mutableValue() = val;        const int64_t n = getOutEdgeIterator().size();        sendMessageToAllNeighbors(val / n);    }};class VERTEX_CLASS_NAME(Graph): public Graph {public:    VERTEX_CLASS_NAME(Aggregator)* aggregator;public:    // argv[0]: PageRankVertex.so    // argv[1]: <input path>    // argv[2]: <output path>    void init(int argc, char* argv[]) {        setNumHosts(5);        setHost(0, "localhost", 1411);        setHost(1, "localhost", 1421);        setHost(2, "localhost", 1431);        setHost(3, "localhost", 1441);        setHost(4, "localhost", 1451);        if (argc < 3) {           printf ("Usage: %s <input path> <output path>\n", argv[0]);           exit(1);        }        m_pin_path = argv[1];        m_pout_path = argv[2];        aggregator = new VERTEX_CLASS_NAME(Aggregator)[1];        regNumAggr(1);        regAggr(0, &aggregator[0]);    }    void term() {        delete[] aggregator;    }};/* STOP: do not change the code below. */extern "C" Graph* create_graph() {    Graph* pgraph = new VERTEX_CLASS_NAME(Graph);    pgraph->m_pin_formatter = new VERTEX_CLASS_NAME(InputFormatter);    pgraph->m_pout_formatter = new VERTEX_CLASS_NAME(OutputFormatter);    pgraph->m_pver_base = new VERTEX_CLASS_NAME();    return pgraph;}extern "C" void destroy_graph(Graph* pobject) {    delete ( VERTEX_CLASS_NAME()* )(pobject->m_pver_base);    delete ( VERTEX_CLASS_NAME(OutputFormatter)* )(pobject->m_pout_formatter);    delete ( VERTEX_CLASS_NAME(InputFormatter)* )(pobject->m_pin_formatter);    delete ( VERTEX_CLASS_NAME(Graph)* )pobject;}

执行命令：

1. source bin/setenv
$ . bin/setenv
2. build example
$ cd example
$ make
3. run example
$ start-graphlite example/PageRankVertex.so Input/facebookcombined_4w Output/out