diff --git a/tensorflow-ops/src/TensorFlow/EmbeddingOps.hs b/tensorflow-ops/src/TensorFlow/EmbeddingOps.hs index 96ee040..c6d2718 100644 --- a/tensorflow-ops/src/TensorFlow/EmbeddingOps.hs +++ b/tensorflow-ops/src/TensorFlow/EmbeddingOps.hs @@ -25,7 +25,7 @@ import Control.Monad (zipWithM) import Data.Int (Int32, Int64) import Data.List (genericLength) import TensorFlow.Build (Build, colocateWith, render) -import TensorFlow.Ops () -- Num instance for Tensor +import TensorFlow.Ops (shape, scalar, vector) -- Also Num instance for Tensor import TensorFlow.Tensor (Tensor, Value) import TensorFlow.Types (OneOf, TensorType) import qualified TensorFlow.GenOps.Core as CoreOps @@ -56,24 +56,33 @@ embeddingLookup :: forall a b v . -> Tensor Value b -- ^ A `Tensor` with type `int32` or `int64` -- containing the ids to be looked up in `params`. - -- The ids are required to be flat on entry and have - -- fewer than 2^31 entries. + -- The ids are required to have fewer than 2^31 + -- entries. -> Build (Tensor Value a) -- ^ A dense tensor with shape `shape(ids) + shape(params)[1:]`. -embeddingLookup params@(p1 : _) ids = - go (np :: Int32) - where - go 1 = colocateWith p1 (render $ CoreOps.gather p1 ids) - go _ = CoreOps.dynamicStitch pindices <$> partitionedResult - np = genericLength params - pAssignments = CoreOps.cast (ids `CoreOps.mod` np) - newIds = ids `CoreOps.div` np - originalIndices = CoreOps.range 0 (CoreOps.size ids) 1 - -- Partition list of ids based on assignments into np separate lists - gatherIds = CoreOps.dynamicPartition np newIds pAssignments - -- Similarly, partition the original indices. - pindices = CoreOps.dynamicPartition np originalIndices pAssignments - -- Do np separate lookups, finding embeddings for plist[p] in params[p] - partitionedResult = zipWithM - (\p g -> colocateWith p $ render $ CoreOps.gather p g) - params gatherIds +embeddingLookup [p0] ids = colocateWith p0 (render $ CoreOps.gather p0 ids) +embeddingLookup params@(p0 : _) ids = do + -- Do np separate lookups, finding embeddings for plist[p] in params[p] + partitionedResult <- zipWithM + (\p g -> colocateWith p $ render $ CoreOps.gather p g) + params gatherIds + let unshapedResult = CoreOps.dynamicStitch pindices partitionedResult + -- Shape restoration is not as optimal as it would be with client + -- side shape tracking. + paramShape <- colocateWith p0 (render (shape p0)) + let finalShape = CoreOps.concat 0 [shape ids, tailShape] + tailShape = CoreOps.slice paramShape (singleton 1) (singleton (-1)) + render $ CoreOps.reshape unshapedResult finalShape + where + np = genericLength params + flatIds = CoreOps.reshape ids (singleton (-1)) + pAssignments = CoreOps.cast (flatIds `CoreOps.mod` np) + newIds = flatIds `CoreOps.div` np + originalIndices = CoreOps.range 0 (CoreOps.size flatIds) 1 + -- Partition list of ids based on assignments into np separate lists + gatherIds = CoreOps.dynamicPartition np newIds pAssignments + -- Similarly, partition the original indices. + pindices = CoreOps.dynamicPartition np originalIndices pAssignments + singleton i = vector [i :: Int32] + +embeddingLookup [] _ = error "embeddingLookup requires params to be non empty"