如何在ocaml中可视化/绘制自动机？

Question

我正在做自动机的组合.所以在最后,我想绘制组合自动机.所以在ocaml中有没有任何库？或者是否有为任何图形可视化工具编写的ocaml包装器？我已经谷歌搜索了,但没有得到太多的ocaml.关于ocamlgraph的任何评论？我将在组合自动机中获得超过100个州.

Answer 1

使用ocamlgraph - 它是一个图形库,可以为你生成一个dot/graphviz文件,但也可以做很多其他可能对处理你的自动机感兴趣的东西.该库可以执行固定点,生成树,图搜索,查找强连接组件等.

下面是一些带有标记边缘的有向图的完整示例+用于执行深度优先搜索+模块的模块,用于创建它的点表示:

(* representation of a node -- must be hashable *)
module Node = struct
   type t = int
   let compare = Pervasives.compare
   let hash = Hashtbl.hash
   let equal = (=)
end

(* representation of an edge -- must be comparable *)
module Edge = struct
   type t = string
   let compare = Pervasives.compare
   let equal = (=)
   let default = ""
end

(* a functional/persistent graph *)
module G = Graph.Persistent.Digraph.ConcreteBidirectionalLabeled(Node)(Edge)

(* more modules available, e.g. graph traversal with depth-first-search *)
module D = Graph.Traverse.Dfs(G)

(* module for creating dot-files *)
module Dot = Graph.Graphviz.Dot(struct
   include G (* use the graph module from above *)
   let edge_attributes (a, e, b) = [`Label e; `Color 4711]
   let default_edge_attributes _ = []
   let get_subgraph _ = None
   let vertex_attributes _ = [`Shape `Box]
   let vertex_name v = string_of_int v
   let default_vertex_attributes _ = []
  let graph_attributes _ = []
end)

你可以写你的程序; 例如:

(* work with the graph ... *)
let _ =
   let g = G.empty in
   let g = G.add_edge_e ...
   ...
   let file = open_out_bin "mygraph.dot" in
   let () = Dot.output_graph file g in
   ...
   if D.has_cycle g then ... else ...

Answer 2

我只是将自动机写为文本到文件(格式适合graphviz),然后对该文件运行graphviz.