src/Values.hs

   1 {-# LANGUAGE FlexibleInstances #-}
   2
   3 module Values
   4 where
   5
   6 import Data.Array.Repa (
   7   Array,
   8   Z(..),
   9   (:.)(..),
  10   DIM1,
  11   DIM2,
  12   DIM3,
  13   extent,
  14   fromList,
  15   unsafeIndex,
  16   reshape,
  17   size
  18   )
  19
  20 import Data.Array.Repa.IO.Vector (readVectorFromTextFile,
  21                                   writeVectorToTextFile)
  22 import System.FilePath ()
  23 import Test.QuickCheck (Arbitrary(..), Gen, choose, vectorOf)
  24
  25
  26 import ScaleFactor
  27
  28
  29 type Values sh = Array sh Double
  30 type Values1D = Values DIM1
  31 type Values2D = Values DIM2
  32 type Values3D = Values DIM3
  33
  34
  35 instance Arbitrary Values3D where
  36     arbitrary = do
  37       -- I declare not to care about empty lists.
  38       x_dim <- choose (1, 27)
  39       y_dim <- choose (1, 27)
  40       z_dim <- choose (1, 27)
  41       elements <- vectorOf (x_dim * y_dim * z_dim) (arbitrary :: Gen Double)
  42       let new_shape = (Z :. x_dim :. y_dim :. z_dim)
  43       let three_d = Data.Array.Repa.fromList new_shape elements
  44       return three_d
  45
  46
  47 read_values_1d :: FilePath -> IO Values1D
  48 read_values_1d = readVectorFromTextFile
  49
  50
  51 read_values_3d :: DIM3 -> FilePath -> IO Values3D
  52 read_values_3d sh path = do
  53   one_d <- read_values_1d path
  54   return $ reshape sh one_d
  55
  56 write_values_1d :: Values3D -> FilePath -> IO ()
  57 write_values_1d v3d path = do
  58   let size3d = size $ extent v3d
  59   let shape1d = (Z :. size3d)
  60   let v1d = reshape shape1d v3d
  61   writeVectorToTextFile v1d path
  62
  63 empty3d :: Values3D
  64 empty3d = Data.Array.Repa.fromList (Z :. 0 :. 0 :. 0) []
  65
  66
  67 dims :: Values3D -> (Int, Int, Int)
  68 dims v3d =
  69     let (Z :. x :. y :. z) = extent v3d
  70     in
  71       (x,y,z)
  72
  73
  74 idx :: Values3D -> Int -> Int -> Int -> Double
  75 idx v3d i j k =
  76     unsafeIndex v3d shape
  77     where
  78       shape :: DIM3
  79       shape = (Z :. i :. j :. k)
  80
  81
  82 zoom_shape :: ScaleFactor -> DIM3 -> DIM3
  83 zoom_shape (sfx, sfy, sfz) sh =
  84     let (Z :. x :. y :. z) = sh
  85         x' = x * sfx
  86         y' = y * sfy
  87         z' = z * sfz
  88     in
  89       (Z :. x' :. y' :. z')
  90
  91
  92 drop_z :: DIM3 -> DIM2
  93 drop_z (Z :. 1 :. y :. x) = (Z :. y :. x)
  94 drop_z _ = error "can't drop the z-dimension unless its size is 1"