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Boost.Graph:使用名称保存并加载boost :: adjacency_list

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一个boost :: adjaceny_list我能够得到并设置图形的名称 . 可悲的是,我无法将其保存并加载到文件中 . 我可以保存和加载顶点和边缘,但图形属性的工作方式不同 .

在下面的完整测试编译代码中,我展示:

  • 如何使用名称创建空的有向图

  • 设置并获取图表的名称

  • 加载并保存图表

  • main:设置图形名称,保存,加载,检查结果是否仍具有该名称

首先是基础工作:

  • 如何使用名称创建空的有向图

  • 设置并获取图表的名称

这些功能接近于简单:

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

boost::adjacency_list<
  boost::vecS,
  boost::vecS,
  boost::directedS,
  boost::no_property,
  boost::no_property,
  boost::property<boost::graph_name_t,std::string>
>
create_empty_directed_graph_with_graph_name() noexcept
{
  return {};
}

template <typename graph>
void set_graph_name(const std::string& name, graph& g) noexcept
{
  get_property(g, boost::graph_name) = name;
}

template <typename graph>
std::string get_graph_name(const graph& g) noexcept
{
  return get_property(g, boost::graph_name
  );
}

我想去上班的考试:

int main()
{
  const std::string dot_filename{"test.dot"};
  auto g = create_empty_directed_graph_with_graph_name();
  set_graph_name("TestGraph", g);
  save_graph_with_graph_name_to_dot(g, dot_filename);
  const auto h = load_directed_graph_with_graph_name_from_dot(dot_filename);
  assert(get_graph_name(g) == get_graph_name(h));
}

步骤是:(1)设置图形名称(2)保存(3)加载图形(4)检查是否具有相同名称

我问的代码是保存 . 我用这样的名字保存图表:

template <typename graph>
void save_graph_with_graph_name_to_dot(
  const graph& g, const std::string& filename
)
{
  std::ofstream f(filename);
  boost::write_graphviz(
    f,
    g,
    boost::default_writer(),
    boost::default_writer(),
    [g](std::ostream& os) {
      os << "name=\""
        << get_graph_name(g)
        << "\";\n";
    }
  );
}

我不确定这是否可行 . 它生成以下.dot文件:

digraph G {
name="TestGraph";
}

我想知道它是否应该不会说'digraph TestGraph',但它被接受为有效的.dot文件 .

加载此文件是我被困在的地方 . 我甚至不知道如何编译它 . 我知道如何(保存和)加载任何类型的边和顶点(见a Boost.Graph tutorial),但在这里我迷路了 . 这是我的尝试:

boost::adjacency_list<
  boost::vecS,
  boost::vecS,
  boost::directedS,
  boost::no_property,
  boost::no_property,
  boost::property<boost::graph_name_t, std::string>
>
load_directed_graph_with_graph_name_from_dot(
  const std::string& dot_filename
)
{
  std::ifstream f(dot_filename.c_str());
  auto g = create_empty_directed_graph_with_graph_name();

  //#define TODO_KNOW_HOW_TO_LOAD_A_GRAPH_ITS_NAME
  #ifdef TODO_KNOW_HOW_TO_LOAD_A_GRAPH_ITS_NAME
  boost::dynamic_properties p;
  p.property("name",get_property(g,boost::graph_name)); //Something like this?
  #else
  boost::dynamic_properties p(
    boost::ignore_other_properties
  );
  #endif
  boost::read_graphviz(f,g,p);
  return g;
}

我希望有人知道如何保存和加载带有名称的图形 . 它不应该太难,不是吗?

这是完整的完整列表:

#include <boost/graph/adjacency_list.hpp>
#include <boost/graph/graphviz.hpp>
#include <boost/graph/properties.hpp>
#include <cassert>
#include <fstream>
#include <string>

boost::adjacency_list<
  boost::vecS,
  boost::vecS,
  boost::directedS,
  boost::no_property,
  boost::no_property,
  boost::property<boost::graph_name_t,std::string>
>
create_empty_directed_graph_with_graph_name() noexcept
{
  return {};
}

template <typename graph>
void set_graph_name(const std::string& name, graph& g) noexcept
{
  get_property(g, boost::graph_name) = name;
}

template <typename graph>
std::string get_graph_name(const graph& g) noexcept
{
  return get_property(g, boost::graph_name
  );
}

template <typename graph>
void save_graph_with_graph_name_to_dot(
  const graph& g, const std::string& filename
)
{
  std::ofstream f(filename);
  boost::write_graphviz(
    f,
    g,
    boost::default_writer(),
    boost::default_writer(),
    //Unsure if this results in a graph that can be loaded correctly from a .dot file
    [g](std::ostream& os) {
      os << "name=\""
        << get_graph_name(g)
        << "\";\n";
    }
  );
}

boost::adjacency_list<
  boost::vecS,
  boost::vecS,
  boost::directedS,
  boost::no_property,
  boost::no_property,
  boost::property<boost::graph_name_t, std::string>
>
load_directed_graph_with_graph_name_from_dot(
  const std::string& dot_filename
)
{
  std::ifstream f(dot_filename.c_str());
  auto g = create_empty_directed_graph_with_graph_name();

  //#define TODO_KNOW_HOW_TO_LOAD_A_GRAPH_ITS_NAME
  #ifdef TODO_KNOW_HOW_TO_LOAD_A_GRAPH_ITS_NAME
  boost::dynamic_properties p;
  p.property("name",get_property(g,boost::graph_name)); //Something like this?
  #else
  boost::dynamic_properties p(
    boost::ignore_other_properties
  );
  #endif
  boost::read_graphviz(f,g,p);
  return g;
}

int main()
{
  const std::string dot_filename{"test.dot"};
  auto g = create_empty_directed_graph_with_graph_name();
  set_graph_name("TestGraph", g);
  save_graph_with_graph_name_to_dot(g, dot_filename);
  const auto h = load_directed_graph_with_graph_name_from_dot(dot_filename);
  assert(get_graph_name(g) == get_graph_name(h));
}

1 回答

  • 0

    cv_and_he:谢谢!我确实看到了那个页面,但是很难看到它!

    答:代码的加载部分需要更改为:

    boost::adjacency_list<
      boost::vecS,
      boost::vecS,
      boost::directedS,
      boost::no_property,
      boost::no_property,
      boost::property<boost::graph_name_t, std::string>
    >
    load_directed_graph_with_graph_name_from_dot(
      const std::string& dot_filename
    )
    {
      using graph = boost::adjacency_list<
        boost::vecS,
        boost::vecS,
        boost::directedS,
        boost::no_property,
        boost::no_property,
        boost::property<boost::graph_name_t, std::string>
      >;
    
    
      std::ifstream f(dot_filename.c_str());
      auto g = create_empty_directed_graph_with_graph_name();
    
      boost::ref_property_map<graph*,std::string>
        graph_name(get_property(g,boost::graph_name)
      );
    
      boost::dynamic_properties dp;
      dp.property("name",graph_name);
    
      boost::read_graphviz(f,g,dp);
      return g;
    }
    

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