src/Gargantext/Viz/Graph/FGL.hs

   1 {-| Module      : Gargantext.Viz.Graph.FGL
   2 Description : FGL main functions used in Garg
   3 Copyright   : (c) CNRS, 2017-Present
   4 License     : AGPL + CECILL v3
   5 Maintainer  : team@gargantext.org
   6 Stability   : experimental
   7 Portability : POSIX
   8
   9 Main FGL funs/types to ease portability with IGraph.
  10
  11 -}
  12
  13 {-# LANGUAGE NoImplicitPrelude #-}
  14 {-# LANGUAGE ConstraintKinds   #-}
  15
  16 module Gargantext.Viz.Graph.FGL where
  17
  18 import Gargantext.Prelude
  19 import qualified Data.Graph.Inductive as FGL
  20 import Data.List as List
  21 ------------------------------------------------------------------
  22 -- | Main Types
  23
  24 type Graph_Undirected = FGL.Gr () ()
  25 type Graph_Directed   = FGL.Gr () ()
  26
  27 type Graph = FGL.Graph
  28 type Node = FGL.Node -- Int
  29 type Edge = FGL.Edge -- (Int, Int)
  30
  31 ------------------------------------------------------------------
  32 -- | Main Functions
  33 mkGraph :: [Node] -> [Edge] -> Graph_Undirected
  34 mkGraph = FGL.mkUGraph
  35
  36 neighbors :: Graph gr => gr a b -> Node -> [Node]
  37 neighbors = FGL.neighbors
  38
  39 -- | TODO bug: if graph is undirected, we need to filter
  40 -- nub . (map (\(n1,n2) -> if n1 < n2 then (n1,n2) else (n2,n1))) . FGL.edges
  41 edges :: Graph gr => gr a b -> [Edge]
  42 edges = FGL.edges
  43
  44 nodes :: Graph gr => gr a b -> [Node]
  45 nodes = FGL.nodes
  46
  47 ------------------------------------------------------------------------
  48 -- | Graph Tools
  49
  50 filterNeighbors :: Graph_Undirected -> Node -> [Node]
  51 filterNeighbors g n = List.nub $ neighbors g n
  52
  53 -- Q: why not D.G.I.deg ? (Int as result)
  54 degree :: Graph_Undirected -> Node -> Double
  55 degree g n = fromIntegral $ List.length (filterNeighbors g n)
  56
  57 vcount :: Graph_Undirected -> Double
  58 vcount = fromIntegral . List.length . List.nub . nodes
  59
  60 -- | TODO tests, optim and use IGraph library, fix IO ?
  61 ecount :: Graph_Undirected -> Double
  62 ecount = fromIntegral . List.length . List.nub . edges
  63
  64
  65 ------------------------------------------------------------------
  66 -- | Main sugared functions
  67
  68 mkGraphUfromEdges :: [(Int, Int)] -> Graph_Undirected
  69 mkGraphUfromEdges es = mkGraph ns es
  70   where
  71     ns = List.nub (a <> b)
  72       where
  73         (a, b) = List.unzip es
  74