minor

src/IGraph.hs

@@ -132,13 +132,13 @@ mkGraph (n, vattr) (es,eattr) = runST $ do
     zip' a b | length a /= length b = error "incorrect length"
              | otherwise = zipWith (\(x,y) z -> (x,y,z)) a b
 
-fromLabeledEdges :: (Graph d, Hashable v, Read v, Eq v, Show v)
-                 => [(v, v)] -> LGraph d v ()
-fromLabeledEdges es = mkGraph (n, Just labels) (es', Nothing)
+fromLabeledEdges :: (Graph d, Hashable v, Read v, Eq v, Show v, Show e)
+                 => [((v, v), e)] -> LGraph d v e
+fromLabeledEdges es = mkGraph (n, Just labels) (es', Just $ snd $ unzip es)
   where
-    es' = map (f *** f) es
+    es' = map (f *** f) $ fst $ unzip es
       where f x = M.lookupDefault undefined x labelToId
-    labels = nub $ concat [ [a,b] | (a,b) <- es ]
+    labels = nub $ concat [ [a,b] | ((a,b),_) <- es ]
     labelToId = M.fromList $ zip labels [0..]
     n = M.size labelToId
 

src/IGraph/Exporter/GEXF.hs

@@ -21,6 +21,7 @@ data NodeAttr = NodeAttr
     , _nodeLabel :: String
     , _positionX :: Double
     , _positionY :: Double
+    , _nodeZindex :: Int
     } deriving (Show, Read, Eq)
 
 instance Hashable NodeAttr where
@@ -33,6 +34,7 @@ defaultNodeAttributes = NodeAttr
     , _nodeLabel = ""
     , _positionX = 0
     , _positionY = 0
+    , _nodeZindex = 1
     }
 
 data EdgeAttr = EdgeAttr
@@ -40,6 +42,7 @@ data EdgeAttr = EdgeAttr
     , _edgeColour :: AlphaColour Double
     , _edgeWeight :: Double
     , _edgeArrowLength :: Double
+    , _edgeZindex :: Int
     } deriving (Show, Read, Eq)
 
 instance Hashable EdgeAttr where
@@ -51,6 +54,7 @@ defaultEdgeAttributes = EdgeAttr
     , _edgeColour = opaque black
     , _edgeWeight = 1.0
     , _edgeArrowLength = 5.0
+    , _edgeZindex = 0
     }
 
 genXMLTree :: (ArrowXml a, Graph d) => LGraph d NodeAttr EdgeAttr -> a XmlTree XmlTree

src/IGraph/Exporter/Graphics.hs

 {-# LANGUAGE FlexibleContexts #-}
-{-# LANGUAGE GADTs #-}
+{-# LANGUAGE GADTs            #-}
 module IGraph.Exporter.Graphics
     ( renderGraph
     , graphToDiagram
     ) where
 
-import Diagrams.Prelude
-import Diagrams.Size (dims)
-import Diagrams.Backend.Cairo
+import           Data.List              (sortBy)
+import           Data.Ord               (comparing)
+import           Diagrams.Backend.Cairo
+import           Diagrams.Prelude
+import           Diagrams.Size          (dims)
 
-import IGraph
-import IGraph.Exporter.GEXF
+import           IGraph
+import           IGraph.Exporter.GEXF
 
 renderGraph :: Graph d => FilePath -> Double -> Double -> LGraph d NodeAttr EdgeAttr -> IO ()
 renderGraph out w h gr = renderCairo out (dims $ w ^& h) $ graphToDiagram gr
 
 graphToDiagram :: Graph d => LGraph d NodeAttr EdgeAttr -> Diagram B
-graphToDiagram gr = position (map drawNode (nodes gr)) <> mconcat (map drawEdge (edges gr))
+graphToDiagram gr = mconcat $ fst $ unzip $ sortBy (flip (comparing snd)) $
+    map drawNode (nodes gr) ++ map drawEdge (edges gr)
   where
-    drawNode x = ( _positionX nattr ^& _positionY nattr
-                 , circle (_size nattr) # lwO 0 # fcA (_nodeColour nattr) )
+    drawNode x = ( moveTo (_positionX nattr ^& _positionY nattr)
+                          (circle (_size nattr) # lwO 0 # fcA (_nodeColour nattr))
+                 , _nodeZindex nattr )
       where
         nattr = nodeLab gr x
     drawEdge (from, to) = {-arrowBetween'
@@ -27,8 +31,8 @@ graphToDiagram gr = position (map drawNode (nodes gr)) <> mconcat (map drawEdge
                & arrowHead .~ arrowH
                & headLength .~ output (_edgeArrowLength eattr)
         ) start end-}
-        fromVertices [start, end]
-        # lwO (_edgeWeight eattr) # lcA (_edgeColour eattr)
+        ( fromVertices [start, end]
+        # lwO (_edgeWeight eattr) # lcA (_edgeColour eattr), _edgeZindex eattr )
       where
         eattr = edgeLab gr (from, to)
         start = _positionX nattr1 ^& _positionY nattr1

src/IGraph/Structure.hs

@@ -84,7 +84,7 @@ eigenvectorCentrality gr ws = unsafePerformIO $ do
 -- | Google's PageRank
 pagerank :: Graph d
          => LGraph d v e
-         -> Maybe [Double]
+         -> Maybe [Double]  -- ^ edge weights
          -> Double  -- ^ damping factor, usually around 0.85
          -> [Double]
 pagerank gr ws d = unsafePerformIO $ alloca $ \p -> do

stack.yaml

@@ -4,4 +4,4 @@ flags:
 packages:
     - '.'
 extra-deps: []
-resolver: lts-5.5
+resolver: lts-6.1