From 4b6d1dbe4d79641d93676a311baa849b659cd12f Mon Sep 17 00:00:00 2001
From: Yann Herklotz <ymherklotz@gmail.com>
Date: Mon, 5 Nov 2018 22:04:48 +0000
Subject: Generate random undirected graph

---
 src/Main.hs | 49 ++++++++++++++++++++-----------------------------
 1 file changed, 20 insertions(+), 29 deletions(-)

(limited to 'src')

diff --git a/src/Main.hs b/src/Main.hs
index c52ad16..6aff865 100644
--- a/src/Main.hs
+++ b/src/Main.hs
@@ -6,42 +6,33 @@ import Data.GraphViz
 import Data.Graph.Inductive.Example (clr479, dag4)
 import Data.Graph.Inductive.Graph
 import Data.Graph.Inductive.PatriciaTree
+import Data.GraphViz.Attributes.Complete
+import Data.Text.Lazy
+import Data.GraphViz.Commands
+import Data.Graph.Generators.Random.WattsStrogatz
+import System.Random.MWC
+import Data.Graph.Generators.FGL
+import Data.Graph.Generators
 
 type Input = Bool
 
 data Gate = Nand
-          deriving (Show)
+          | And
+          | Or
+          deriving (Show, Eq, Ord)
 
-data Circuit a = In a
-               | Node Gate (Circuit a) (Circuit a)
-               deriving (Show)
+instance Labellable Gate where
+  toLabelValue gate = StrLabel . pack $ show gate
 
 instance Arbitrary Gate where
-  arbitrary = return Nand
+  arbitrary = elements [Nand, And, Or]
 
-instance (Arbitrary a) => Arbitrary (Circuit a) where
-  arbitrary = do
-    x <- arbitrary
-    frequency [(1, return (In x)), (1, arbNode)]
-      where
-        arbNode = Node <$> arbitrary <*> arbitrary <*> arbitrary
+randomTree :: Gr Gate String
+randomTree = mkGraph [(1, Nand), (2, Nand), (3, Or), (4, Nand), (5, Nand), (6, Nand), (7, Or)] [(3, 1, ""), (7, 1, ""), (5, 1, ""), (6, 2, ""), (7, 2, ""), (5, 2, ""), (1, 4, ""), (2, 4, ""), (3, 4, ""), (6, 4, "")]
 
-eval :: (Bits a) => Circuit a -> a
-eval (In val) = val
-eval (Node Nand c1 c2) = complement $ eval c1 .&. eval c2
-
-visualize :: (Show a) => Circuit a -> Gr String String
-visualize circ =
-  graph Nothing 0 (empty :: Gr String String) circ
-  where
-    graph parent nl graph circ =
-      let newNode str graph = (head $ newNodes 1 graph, str) in
-      case (parent, circ) of
-        (Nothing, (In val)) ->
-          insNode (newNode "IN" graph) graph
-        _ ->
-          graph
-
-main :: IO ()
+main :: IO FilePath
 --main = sample (arbitrary :: Gen (Circuit Input))
-main = preview $ visualize (In True)
+main = do
+  gen <- withSystemRandom . asGenIO $ return
+  gr <- wattsStrogatzGraph gen 50 3 0.6
+  runGraphviz (graphToDot nonClusteredParams (graphInfoToUGr gr)) Png "output.png"
-- 
cgit