Question

我有一个类型为

的邻接列表

boost::adjacency_list<boost::setS, boost::vecS, boost::directedS, GraphData>

其中GraphData是一个包含名称的结构

struct GraphItem
{
    std::string Name;
}

我能够将图形写入xml

void WriteGraph() {
     boost::dynamic_properties dp;

     dp.property("Name", make_transform_value_property_map(&Name, 
     boost::get(vertex_bundle, graph)));

     boost::write_graphml(filename, graph, dp, true); 
}

std::string Name(boost::vertex_bundle_type<Graph>::type v) {
    std::ostringstream oss;
    oss << v.Name;
    return oss.str();
}

我将XML作为

<graphml>
  <key id="key0" for="node" attr.name="Name" attr.type="string" />
  <graph id="G" edgedefault="directed" parse.nodeids="canonical" 
   parse.edgeids="canonical" parse.order="nodesfirst">
    <node id="n0">
      <data key="key0">A</data>
    </node>
    <node id="n1">
      <data key="key0">D</data>
    </node>
    <node id="n2">
      <data key="key0">B</data>
    </node>
    <node id="n3">
      <data key="key0">C</data>
    </node>
    <edge id="e0" source="n0" target="n1">
    </edge>
    <edge id="e1" source="n2" target="n3">
    </edge>
  </graph>
</graphml>

当我阅读图表时

void ReadGraph() {
    boost::dynamic_properties dp;
    std::ifstream file(fileName);
    boost::read_graphml(file, graph, dp);
}

这是崩溃说找不到属性名称。如果我使用 ignore_other_properties 作为属性，

boost::dynamic_properties dp(ignore_other_properties);

它有效，但我没有在图顶点中获得任何图形项。

Answer 1

图表不为空，你得到：

Index Build (background) Index Build (background): 5311727/27231147 19%

或者使用XML：https://paste.ubuntu.com/p/c4tGmxGssJ/

当然，您想要读取name属性。为此，您显然需要使用动态属性映射注册该属性。

注意您可以更简单地访问属性包的成员：

0 --> 1 
1 --> 
2 --> 3 
3 -->

完整演示

    dp.property("Name", boost::get(&GraphData::Name, graph));

打印

#include <boost/graph/adjacency_list.hpp>
#include <boost/graph/graphml.hpp>

struct GraphData {
    std::string Name;
};

using Graph = boost::adjacency_list<boost::setS, boost::vecS, boost::directedS, GraphData>;

Graph ReadGraph(std::string const& fileName) {
    Graph graph;
    boost::dynamic_properties dp;
    dp.property("Name", boost::get(&GraphData::Name, graph));

    std::ifstream file(fileName);
    boost::read_graphml(file, graph, dp);

    return graph;
}

void WriteGraph(std::ostream& os, Graph& graph) {
    boost::dynamic_properties dp;
    dp.property("Name", get(&GraphData::Name, graph));

    boost::write_graphml(os, graph, dp, true); 
}

#include <boost/graph/graph_utility.hpp>

int main() {
    Graph g = ReadGraph("input.txt");
    print_graph(g, get(&GraphData::Name, g));

    // or as XML
    WriteGraph(std::cout << "==== XML version: ====\n\n", g);
}

Boost Read_graphml没有正确读取xml它给出了所有顶点但它们都是空的

1 个答案:

完整演示