Safe Haskell	None
Language	Haskell2010

DataFrame.Internal.RadixRank

Description

Stable rank of a set of group representatives by ascending unsigned hash order. Shared by the sequential and parallel group-by canonical-ordering steps so they stay bit-for-bit identical. O(ng) stable LSD radix sort.

Synopsis

rankByHash :: PrimMonad m => (Int -> m Int) -> Int -> m (Vector Int)
sortKey :: Int -> Int

Documentation

rankByHash :: PrimMonad m => (Int -> m Int) -> Int -> m (Vector Int) Source #

See the module header. readHash supplies the hash of local group gid.

sortKey :: Int -> Int Source #

Unsigned sort key of a hash: ascending Word64 order of sortKey h equals ascending signed-Int order of h. Reinterpreted to Int for the byte-wise radix passes (the byte mask makes the sign extension irrelevant).