Merge pull request #49 from HuwCampbell/topic/exact-hotmap

Topic/exact hotmap

examples/main/shakespeare.hs

@@ -41,6 +41,9 @@ import           System.IO.Unsafe ( unsafeInterleaveIO )
 -- This network is able to learn and generate simple words in
 -- about an hour.
 --
+-- Grab the input from
+-- https://raw.githubusercontent.com/karpathy/char-rnn/master/data/tinyshakespeare/input.txt
+--
 -- This is a first class recurrent net.
 --
 -- The F and R types are tagging types to ensure that the runner and
@@ -69,7 +72,7 @@ loadShakespeare :: FilePath -> ExceptT String IO (Vector Int, M.Map Char Int, Ve
 loadShakespeare path = do
   contents     <- lift $ readFile path
   let annotated = annotateCapitals contents
-  (m,cs)       <- ExceptT . return . note "Couldn't fit data in hotMap" $ hotMap (Proxy :: Proxy 40) annotated
+  (m,cs)       <- ExceptT . return $ hotMap (Proxy :: Proxy 40) annotated
   hot          <- ExceptT . return . note "Couldn't generate hot values" $ traverse (`M.lookup` m) annotated
   return (V.fromList hot, m, cs)
 

grenade.cabal

@@ -42,12 +42,9 @@ library
                      , containers                      >= 0.5         && < 0.6
                      , cereal                          >= 0.5         && < 0.6
                      , deepseq                         >= 1.4         && < 1.5
-                     , exceptions                      == 0.8.*
                      , hmatrix                         == 0.18.*
                      , MonadRandom                     >= 0.4         && < 0.6
-                     , mtl                             >= 2.2.1       && < 2.3
                      , primitive                       >= 0.6         && < 0.7
-                     , text                            == 1.2.*
                      , singletons                      >= 2.1         && < 2.4
                      , vector                          >= 0.11        && < 0.13
 

src/Grenade/Utils/OneHot.hs

@@ -52,15 +52,16 @@ oneHot hot =
 
 -- | Create a one hot map from any enumerable.
 --   Returns a map, and the ordered list for the reverse transformation
-hotMap :: (Ord a, KnownNat n) => Proxy n -> [a] -> Maybe (Map a Int, Vector a)
+hotMap :: (Ord a, KnownNat n) => Proxy n -> [a] -> Either String (Map a Int, Vector a)
 hotMap n as =
   let len  = fromIntegral $ natVal n
       uniq = [ c | (c:_) <- group $ sort as]
       hotl = length uniq
-  in if hotl <= len
+  in if hotl == len
       then
-        Just (M.fromList $ zip uniq [0..], V.fromList uniq)
+        Right (M.fromList $ zip uniq [0..], V.fromList uniq)
-      else Nothing
+      else
+        Left ("Couldn't create hotMap of size " ++ show len ++ " from vector with " ++ show hotl ++ " unique characters")
 
 -- | From a map and value, create a 1D Shape
 --   with one index hot (1) with the rest 0.