FunctorCombo.ParScan

Composable parallel scanning from http://conal.net/blog/posts/composable-parallel-scanning/

Documentation

class Scan f where

Parallel scans. prefixScan accumulates moving left-to-right, while suffixScan accumulates moving right-to-left.

Methods

prefixScan :: Monoid m => f m -> PreScanO f m

suffixScan :: Monoid m => f m -> SufScanO f m

Instances

Scan Id

Scan Pair

Scan (Const x)

(Scan g, Scan f, Functor f, Applicative g) => Scan ((:.) g f)

(Scan f, Scan g) => Scan ((:+:) f g)

(Scan f, Scan g, Functor f, Functor g) => Scan ((:*:) f g)

type PreScanO f a = (f a, a)

type SufScanO f a = (a, f a)

prefixScanEnc :: (EncodeF f, Scan (Enc f), Monoid m) => f m -> PreScanO f m

suffixScanEnc :: (EncodeF f, Scan (Enc f), Monoid m) => f m -> SufScanO f m

preScanTweak :: Functor f => (a -> b) -> PreScanO f a -> PreScanO f b

sufScanTweak :: Functor f => (a -> b) -> SufScanO f a -> SufScanO f b

prefixSums :: (Functor f, Scan f, Num a) => f a -> PreScanO f a

suffixSums :: (Functor f, Scan f, Num a) => f a -> SufScanO f a