Boost图设计没有邻接表或邻接矩阵 [英] Boost graph designing without adjacency list or adjacency matrix

问题描述

有没有什么方法来创建图形结构，而不使用邻接列表或邻接矩阵在C ++ boost？ （使用指向其邻居顶点的指针的顶点结构）

Is there any way to create a graph structure without using adjacency list or adjacency matrix in C++ boost? (a vertex structure using pointers which points to its neighbour vertices)

推荐答案

当然， traits，这意味着你基本上处理顶点和边缘，即使在你的代码中，他们被称为节点和链接。

It is possible, of course, provided your data has "traits" of a theoretical graph, meaning you essentially deal with "vertices" and "edges", even if in your code they are called, say, "nodes" and "links".

此结构称为BGL图适配器。这可能是一个有点具有挑战性的C ++运动，但。一般的想法是教BGL有关你的数据的很多细节：

This construct is called "BGL graph adapter". It can be a little challenging C++ exercise, though. The general idea is to teach BGL a lot of details about your data:

1. 你的数据的C ++类型在你的想象图中意味着什么， / li>
   
2. 如何迭代顶点和边。

所以你定义一个类，比如MyGraph，它通常是一个很轻的重量，然后通过提供BGL的模板专用化来定义其特征 graph_traits ：

So you define a class, say MyGraph, which is typically a very light-weight and just keeps few pointers to your data. Then you define its traits by providing template specialization of BGL graph_traits:

#include <boost/graph/graph_traits.hpp>
namespace boost {
    template <>
    struct graph_traits<MyGraph> 
{
    typedef ... vertex_descriptor; //what plays a role of vertex in your data
    typedef ... edge_descriptor; //what plays a role of edge in your data

    //other typedefs from graph_traits like edge_iterator, out_edge_iterator, etc.

    //plus, you specify "categories" of your graph explaining what types of traversal are
    //available (more the better)
    struct traversal_category
        : public virtual boost::vertex_list_graph_tag
        , public virtual boost::adjacency_graph_tag
        , public virtual boost::bidirectional_graph_tag //means we provide access to in_edges
                                                        //and to out_edges of a given vertex
    {
    };    
};
}

之后，您实现了在图结构上提供访问和迭代器的全局函数，例如：

After that you implement global functions which provide access and iterator over your graph structure, for example:

MyGraph::vertex_descriptor 
source(MyGraph::edge_descriptor e, const MyGraph & g); 

和

std::pair<MyGraph::out_edge_iterator,
          MyGraph::out_edge_iterator>
out_edges(MyGraph::::vertex_descriptor vd, const MyGraph & g )

是在 BGL图概念中预定义的几十个这样的遍历函数。您必须至少提供与上面声明的 traversal_category 相关的那些。

There is about dozens of such traverse functions predefined in BGL graph concepts. You have to provide at least those which relevant for your traversal_category declared above.

如果一切顺利，可以使用BGL算法直接使用您的数据，而不使用预定义的BGL图。

If everything is done right, you can use your data directly with BGL algorithms, without using one of predefined BGL graphs.

在BGL章节如何将现有图表转换为BGL

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