如何在显示多个属性的graphviz中打印图表

Question

我的问题基于：How to print a graph with a single property displayed

我正在使用捆绑属性：

 typedef struct vert{
   std::string name;
 };

 typedef struct edge{
   int capacity;
   int weight;
 }; 

typedef adjacency_list<listS, vecS, undirectedS, vert, edge> Graph;
Graph g;
vector<int,int> ele;

我在一个应该创建边缘的循环中调用了以下内容：

  edge prop;
  prop.weight = 5;
  prop.capacity = 4;
  add_edge(ele.first,ele.second, prop, g);

此段是将图形打印为点格式。

ofstream dot("graph.dot");
write_graphviz(dot, g, 
  boost::make_label_writer(boost::get(&vert::name, g)),
  boost::make_label_writer(boost::get(&edge::weight, g)),
  boost::make_label_writer(boost::get(&edge::capacity, g)));

错误是：

/usr/include/boost/graph/graphviz.hpp: In function ‘void boost::write_graphviz(std::ostream&, const Graph&, VertexPropertiesWriter, EdgePropertiesWriter, GraphPropertiesWriter, VertexID) [with Graph = boost::adjacency_list<boost::listS, boost::vecS, boost::undirectedS, vert, edge, boost::no_property, boost::listS>, VertexPropertiesWriter = boost::label_writer<boost::bundle_property_map<boost::adjacency_list<boost::listS, boost::vecS, boost::undirectedS, vert, edge, boost::no_property, boost::listS>, long unsigned int, vert, std::basic_string<char, std::char_traits<char>, std::allocator<char> > > >, EdgePropertiesWriter = boost::label_writer<boost::bundle_property_map<boost::adjacency_list<boost::listS, boost::vecS, boost::undirectedS, vert, edge, boost::no_property, boost::listS>, boost::detail::edge_desc_impl<boost::undirected_tag, long unsigned int>, edge, int> >, GraphPropertiesWriter = boost::label_writer<boost::bundle_property_map<boost::adjacency_list<boost::listS, boost::vecS, boost::undirectedS, vert, edge, boost::no_property, boost::listS>, boost::detail::edge_desc_impl<boost::undirected_tag, long unsigned int>, edge, int> >, VertexID = boost::vec_adj_list_vertex_id_map<boost::property<boost::vertex_bundle_t, vert, boost::no_property>, long unsigned int>]’:
/usr/include/boost/graph/graphviz.hpp:260:   instantiated from ‘void boost::write_graphviz(std::ostream&, const Graph&, VertexPropertiesWriter, EdgePropertiesWriter, GraphPropertiesWriter) [with Graph = Graph, VertexPropertiesWriter = boost::label_writer<boost::bundle_property_map<boost::adjacency_list<boost::listS, boost::vecS, boost::undirectedS, vert, edge, boost::no_property, boost::listS>, long unsigned int, vert, std::basic_string<char, std::char_traits<char>, std::allocator<char> > > >, EdgePropertiesWriter = boost::label_writer<boost::bundle_property_map<boost::adjacency_list<boost::listS, boost::vecS, boost::undirectedS, vert, edge, boost::no_property, boost::listS>, boost::detail::edge_desc_impl<boost::undirected_tag, long unsigned int>, edge, int> >, GraphPropertiesWriter = boost::label_writer<boost::bundle_property_map<boost::adjacency_list<boost::listS, boost::vecS, boost::undirectedS, vert, edge, boost::no_property, boost::listS>, boost::detail::edge_desc_impl<boost::undirected_tag, long unsigned int>, edge, int> >]’
file_format.cc:194:   instantiated from here
/usr/include/boost/graph/graphviz.hpp:236: error: no match for call to ‘(boost::label_writer<boost::bundle_property_map<boost::adjacency_list<boost::listS, boost::vecS, boost::undirectedS, vert, edge, boost::no_property, boost::listS>, boost::detail::edge_desc_impl<boost::undirected_tag, long unsigned int>, edge, int> >) (std::basic_ostream<char, std::char_traits<char> >&)’

这对我来说很奇怪，因为它有效：

write_graphviz(dot, g,
  boost::make_label_writer(boost::get(&vert_info::name, g)));

并输出以下内容：

graph G {
0[label="0"];
1[label="1"];
2[label="2"];
3[label="3"];
4[label="4"];
5[label="5"];
6[label="6"];
7[label="7"];
8[label="8"];
9[label=""];  // this is another problem that I will have to fix but beside the point
0--9 ;
0--5 ;
0--2 ;
0--1 ;
...
...
}

我的目标是标记每个节点，并标记每个边的容量和权重。

Answer 1

您可以在write_graphviz 的所有重载列表中找到here。第一个错误的原因是您尝试使用的重载在其第五个参数中需要一个图形属性编写器。

辅助函数make_label_writer 只是创建一个属性编写器，它将图的顶点或边中的单个属性分配给名为label 的graphviz 顶点或边属性。

为了实现您想要的，您需要创建一个自定义property writer，在其中您将每个边缘属性分配给您需要的graphviz attributes。我个人会使用weight->label 和capacity->taillabel 或headlabel。

template <class WeightMap,class CapacityMap>
class edge_writer {
public:
  edge_writer(WeightMap w, CapacityMap c) : wm(w),cm(c) {}
  template <class Edge>
  void operator()(ostream &out, const Edge& e) const {
    out << "[label=\"" << wm[e] << "\", taillabel=\"" << cm[e] << "\"]";
  }
private:
  WeightMap wm;
  CapacityMap cm;
};

template <class WeightMap, class CapacityMap>
inline edge_writer<WeightMap,CapacityMap> 
make_edge_writer(WeightMap w,CapacityMap c) {
  return edge_writer<WeightMap,CapacityMap>(w,c);
}

最后你的write_graphviz 调用将是：

ofstream dot("graph.dot");
write_graphviz(dot, g, 
  boost::make_label_writer(boost::get(&vert::name, g)),
  make_edge_writer(boost::get(&edge::weight,g),boost::get(&edge::capacity,g)));