奇怪的错误导入点文件 [英] Odd Error Importing DOT files

问题描述

有关我的C ++程序，我需要使用Boost图，后来又输出点文件点文件中读取。不过，我遇到了读入阶段这实在是拧紧了我的程序一个奇怪的错误。

For my C++ program, I need to read in a DOT file using Boost Graph, and later output another DOT file. However, I am encountering a weird error in the read-in stage which is really screwing up my program.

我读入code（Graph类型是一个双向升压图​​的类型定义）

My read-in code (Graph type is a typedef of a bidirectional Boost graph)

void readGraph(Graph& graph, string filename) {

    boost::dynamic_properties dp(boost::ignore_other_properties);

    ifstream fin(filename.c_str());
    boost::read_graphviz(fin, graph, dp);

}

好了，问题的是，在.DOT文件中的节点在错误的顺序读取的 的！我用一个简单的例子.DOT文件，试了一下：

Ok, so the problem is that the nodes in the .DOT file are read in in the wrong order! I tried it with a simple example .DOT file:

digraph G {
0; 1; 2; 3; 4; 5; 6; 7; 8; 9; 10;
0->1; 1->0;
1->2; 2->1;
2->3; 3->2;
3->4; 4->3;
4->5; 5->4;
5->6; 6->5;
6->7; 7->6;
7->8; 8->7;
8->9; 9->8;
9->10; 10->9;
}

这是从节点0到节点10但是，如果我读使用Boost图，并将其输出文件的双向链立即无需改动，就变成：

This is a bi-directional chain from node 0 to node 10. However if I read this file using Boost Graph and output it immediately without changes, it becomes:

digraph G {
0;
1;
2;
3;
4;
5;
6;
7;
8;
9;
10;
0->1 ;
1->3 ;
3->4 ;
4->5 ;
5->6 ;
6->7 ;
7->8 ;
8->9 ;
9->10 ;
10->2 ;
1->0 ;
3->1 ;
4->3 ;
5->4 ;
6->5 ;
7->6 ;
8->7 ;
9->8 ;
10->9 ;
2->10 ;
}

注意，节点2现在莫名其妙地连接到结点10，并且是在链的末端。我曾经做过的没有的阅读和输出图形之间。

Notice, node 2 is now inexplicably connected to node 10, and is at the end of the chain. I have done nothing in between reading and outputting the graph.

注：

• 当我尝试这更复杂.DOT文件，图的拓扑结构是一样的，它只是节点已经被置换了一些奇怪的原因。

• When I try this with more complicated .DOT files, the topology of the graph remains the same, it's just that the nodes have been permuted for some odd reason.

我知道这是一个读，不会写错误，因为当我输出在节目中的顶点和边，他们已经搞砸了。

I know it is a read, not write error, because when I output the vertices and edges during the program, they are already screwed up.

谁能帮我了解并解决这一问题？谢谢你。

Can anyone help me understand and fix this? Thanks.

推荐答案

如果你读了图形和打印（以​​graphviz的格式）再次产生，你会发现，图形是等价（或同构）

If you read the graph and print the resulting again (in graphviz format), you'll find that the graphs are equivalent (or isomorphic):

<大骨节病> 住在Coliru

#include <boost/graph/graphviz.hpp>
#include "/Archive2/45/a4410ef1bd3024/main.cpp" // alias <libs/graph/src/read_graphviz_new.

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

void readGraph(Graph &graph, std::string filename) {
    boost::dynamic_properties dp(boost::ignore_other_properties);

    std::ifstream fin(filename.c_str());
    boost::read_graphviz(fin, graph, dp);
}

int main() {
    Graph g;
    readGraph(g, "input.dot");

    boost::write_graphviz(std::cout, g);
}

通过您的输入：

的输出是显然异Morphic环

The output is clearly iso-morphic:

注意在你自己的问题中显示的输出是一个简单的呢！

NOTE The output shown in your own question is simply that too!

你真正想要的是顶点的ID被保留。

What you actually want is for the vertex ID's to be retained.

在为了做到这一点，你必须存放顶点ID（从点文件中读取）到属性明确。下面是一个例子：

In order to do that, you'll have to store the vertex ID (as read from the dot file) into a property explicitly. Here is an example:

住在Coliru

Live On Coliru

#include <boost/graph/graphviz.hpp>
#include "/Archive2/45/a4410ef1bd3024/main.cpp" // alias <libs/graph/src/read_graphviz_new.

using namespace boost;

struct MyVertex {
    int id;
};

using Graph = adjacency_list<
    vecS, vecS, directedS, 
    MyVertex
>;

void readGraph(Graph &graph, std::string filename) {
    boost::dynamic_properties dp(boost::ignore_other_properties);
    dp.property("node_id", boost::get(&MyVertex::id, graph));

    std::ifstream fin(filename.c_str());
    boost::read_graphviz(fin, graph, dp);
}

int main() {
    Graph g;
    readGraph(g, "input.dot");

    boost::dynamic_properties dp(boost::ignore_other_properties);
    dp.property("node_id", boost::get(&MyVertex::id, g));
    boost::write_graphviz_dp(std::cout, g, dp);
}

生成：

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