Safe Haskell | None |
---|---|
Language | Haskell98 |
This module defines the default specialisation of flows that appears in Data.Repa.Flow. Each stream in the bundle is indexed by a single integer, and stream state is stored using the IO monad.
- type Sources a = Sources Int IO A a
- type Sinks a = Sinks Int IO A a
- type Flow a = (Flow Int IO A a, Windowable A a)
- sourcesArity :: Sources a -> Int
- sinksArity :: Sinks a -> Int
- fromList :: Build a => Int -> [a] -> IO (Sources a)
- fromLists :: Build a => Int -> [[a]] -> IO (Sources a)
- toList1 :: Build a => Int -> Sources a -> IO [a]
- toLists1 :: Build a => Int -> Sources a -> IO [[a]]
- fromArray :: Build a => Int -> Array a -> IO (Sources a)
- fromArrays :: (Elem a, Build a) => Int -> Array (Array a) -> IO (Sources a)
- toArray1 :: (Elem a, Build a) => Int -> Sources a -> IO (Array a)
- toArrays1 :: (Elem a, Build a) => Int -> Sources a -> IO (Array (Array a))
- drainS :: Sources a -> Sinks a -> IO ()
- drainP :: Sources a -> Sinks a -> IO ()
- consumeS :: Bulk A a => Sources a -> (Int -> a -> IO ()) -> IO ()
- replicates_i :: (Flow (Int, a), Build a) => Sources (Int, a) -> IO (Sources a)
- map_i :: (Flow a, Build b) => (a -> b) -> Sources a -> IO (Sources b)
- map_o :: (Flow a, Build b) => (a -> b) -> Sinks b -> IO (Sinks a)
- zipWith_i :: (Flow a, Flow b, Build c) => (a -> b -> c) -> Sources a -> Sources b -> IO (Sources c)
- process_i :: (Flow a, Flow b, Build b) => (s -> a -> (s, Array b)) -> s -> Sources a -> IO (Sources b)
- module Data.Repa.Flow.Auto.ZipWith
- dup_oo :: Sinks a -> Sinks a -> IO (Sinks a)
- dup_io :: Sources a -> Sinks a -> IO (Sources a)
- dup_oi :: Sinks a -> Sources a -> IO (Sources a)
- connect_i :: Sources a -> IO (Sources a, Sources a)
- watch_i :: (Int -> Array A a -> IO ()) -> Sources a -> IO (Sources a)
- watch_o :: (Int -> Array A a -> IO ()) -> Sinks a -> IO (Sinks a)
- trigger_o :: Int -> (Int -> Array A a -> IO ()) -> IO (Sinks a)
- ignore_o :: Int -> IO (Sinks a)
- abandon_o :: Int -> IO (Sinks a)
- head_i :: Flow a => Int -> Int -> Sources a -> IO (Maybe ([a], Sources a))
- concat_i :: (Flow a, Build a) => Sources (Array a) -> IO (Sources a)
- select_i :: (Select n (Array fs), Select' n (Array fs) ~ Array (Select' n fs)) => Nat n -> Sources fs -> IO (Sources (Select' n fs))
- select_o :: (Select n (Array fs), Select' n (Array fs) ~ Array (Select' n fs)) => Nat n -> Sinks (Select' n fs) -> IO (Sinks fs)
- discard_i :: (Discard n (Array fs), Discard' n (Array fs) ~ Array (Discard' n fs)) => Nat n -> Sources fs -> IO (Sources (Discard' n fs))
- discard_o :: (Discard n (Array fs), Discard' n (Array fs) ~ Array (Discard' n fs)) => Nat n -> Sinks (Discard' n fs) -> IO (Sinks fs)
- mask_i :: (Mask ms (Array fs), Mask' ms (Array fs) ~ Array (Mask' ms fs)) => ms -> Sources fs -> IO (Sources (Mask' ms fs))
- mask_o :: (Mask ms (Array fs), Mask' ms (Array fs) ~ Array (Mask' ms fs)) => ms -> Sinks (Mask' ms fs) -> IO (Sinks fs)
- groups_i :: (GroupsDict a, Eq a) => Sources a -> IO (Sources (a, Int))
- groupsBy_i :: GroupsDict a => (a -> a -> Bool) -> Sources a -> IO (Sources (a, Int))
- type GroupsDict a = GroupsDict Int IO A A A a
- foldlS :: (Flow b, Build a) => (a -> b -> a) -> a -> Sources b -> IO (Array A a)
- foldlAllS :: Flow b => (a -> b -> a) -> a -> Sources b -> IO a
- folds_i :: FoldsDict n a b => (a -> b -> b) -> b -> Sources (n, Int) -> Sources a -> IO (Sources (n, b))
- type FoldsDict n a b = FoldsDict Int IO A A A A n a b
- foldGroupsBy_i :: FoldGroupsDict n a b => (n -> n -> Bool) -> (a -> b -> b) -> b -> Sources n -> Sources a -> IO (Sources (n, b))
- type FoldGroupsDict n a b = (BulkI A n, Material A a, Material A n, Material A b)
- finalize_i :: (Int -> IO ()) -> Sources a -> IO (Sources a)
- finalize_o :: (Int -> IO ()) -> Sinks a -> IO (Sinks a)
Flow types
type Sources a = Sources Int IO A a Source
A bundle of stream sources, where the elements of the stream are chunked into arrays.
type Sinks a = Sinks Int IO A a Source
A bundle of stream sinks, where the elements of the stream are chunked into arrays.
sourcesArity :: Sources a -> Int Source
Yield the number of streams in the bundle.
sinksArity :: Sinks a -> Int Source
Yield the number of streams in the bundle.
Conversion
List conversion
fromList :: Build a => Int -> [a] -> IO (Sources a) Source
Given an arity and a list of elements, yield sources that each produce all the elements.
- All elements are stuffed into a single chunk, and each stream is given the same chunk.
fromLists :: Build a => Int -> [[a]] -> IO (Sources a) Source
Like fromList
but take a list of lists.
Each each of the inner lists is packed into a single chunk.
toList1 :: Build a => Int -> Sources a -> IO [a] Source
Drain a single source from a bundle into a list of elements.
- If the index does not specify a valid stream then the result will be empty.
toLists1 :: Build a => Int -> Sources a -> IO [[a]] Source
Drain a single source from a bundle into a list of chunks.
- If the index does not specify a valid stream then the result will be empty.
Array conversion
fromArray :: Build a => Int -> Array a -> IO (Sources a) Source
Given an arity and an array of elements, yield sources that each produce all the elements.
- All elements are stuffed into a single chunk, and each stream is given the same chunk.
fromArrays :: (Elem a, Build a) => Int -> Array (Array a) -> IO (Sources a) Source
Like fromArray
but take an array of arrays.
Each of the inner arrays is packed into a single chunk.
toArray1 :: (Elem a, Build a) => Int -> Sources a -> IO (Array a) Source
Drain a single source from a bundle into an array of elements.
- If the index does not specify a valid stream then the result will be empty.
toArrays1 :: (Elem a, Build a) => Int -> Sources a -> IO (Array (Array a)) Source
Drain a single source from a bundle into an array of elements.
- If the index does not specify a valid stream then the result will be empty.
Evaluation
consumeS :: Bulk A a => Sources a -> (Int -> a -> IO ()) -> IO () Source
Pull all available values from the sources and pass them to the given action.
Flow Operators
Replicating
:: (Flow (Int, a), Build a) | |
=> Sources (Int, a) | Source of segment lengths and values. |
-> IO (Sources a) |
Segmented replicate.
Mapping
If you want to work on a chunk at a time then use
map_i
and
map_o
from Data.Repa.Flow.Generic.
map_i :: (Flow a, Build b) => (a -> b) -> Sources a -> IO (Sources b) Source
Apply a function to all elements pulled from some sources.
map_o :: (Flow a, Build b) => (a -> b) -> Sinks b -> IO (Sinks a) Source
Apply a function to all elements pushed to some sinks.
zipWith_i :: (Flow a, Flow b, Build c) => (a -> b -> c) -> Sources a -> Sources b -> IO (Sources c) Source
Combine corresponding elements of two sources with the given function.
Processing
:: (Flow a, Flow b, Build b) | |
=> (s -> a -> (s, Array b)) | Worker function. |
-> s | Initial state. |
-> Sources a | Input sources. |
-> IO (Sources b) |
Apply a generic stream process to a bundle of sources.
Higher arity zipWith functions.
module Data.Repa.Flow.Auto.ZipWith
Connecting
dup_oo :: Sinks a -> Sinks a -> IO (Sinks a) Source
Send the same data to two consumers.
Given two argument sinks, yield a result sink. Pushing to the result sink causes the same element to be pushed to both argument sinks.
dup_io :: Sources a -> Sinks a -> IO (Sources a) Source
Send the same data to two consumers.
Given an argument source and argument sink, yield a result source. Pulling an element from the result source pulls from the argument source, and pushes that element to the sink, as well as returning it via the result source.
dup_oi :: Sinks a -> Sources a -> IO (Sources a) Source
Send the same data to two consumers.
Like dup_io
but with the arguments flipped.
connect_i :: Sources a -> IO (Sources a, Sources a) Source
Connect an argument source to two result sources.
Pulling from either result source pulls from the argument source. Each result source only gets the elements pulled at the time, so if one side pulls all the elements the other side won't get any.
Watching
watch_i :: (Int -> Array A a -> IO ()) -> Sources a -> IO (Sources a) Source
Hook a worker function to some sources, which will be passed every chunk that is pulled from each source.
- The worker is also passed the source index of the chunk that was pulled.
watch_o :: (Int -> Array A a -> IO ()) -> Sinks a -> IO (Sinks a) Source
Hook a worker function to some sinks, which will be passed every chunk that is pushed to each sink.
- The worker is also passed the source index of the chunk that was pushed.
trigger_o :: Int -> (Int -> Array A a -> IO ()) -> IO (Sinks a) Source
Create a bundle of sinks of the given arity that pass incoming chunks to a worker function.
- This is like
watch_o
, except that the incoming chunks are discarded after they are passed to the worker function
Ignorance
ignore_o :: Int -> IO (Sinks a) Source
Create a bundle of sinks of the given arity that drop all data on the floor.
- Haskell debugging thunks attached to the chunks will be demanded, but thunks attached to elements may not be -- depending on whether the chunk representation is strict in the elements.
abandon_o :: Int -> IO (Sinks a) Source
Create a bundle of sinks of the given arity that drop all data on the floor.
- As opposed to
ignore_o
the sinks are non-strict in the chunks. - Haskell debugging thunks attached to the chunks will *not* be demanded.
Splitting
head_i :: Flow a => Int -> Int -> Sources a -> IO (Maybe ([a], Sources a)) Source
Given a source index and a length, split the a list of that length from the front of the source. Yields a new source for the remaining elements.
- We pull whole chunks from the source stream until we have
at least the desired number of elements. The leftover elements
in the final chunk are visible in the result
Sources
.
Concatenation
concat_i :: (Flow a, Build a) => Sources (Array a) -> IO (Sources a) Source
Concatenate a flow of arrays into a flow of the elements.
Selecting
:: (Select n (Array fs), Select' n (Array fs) ~ Array (Select' n fs)) | |
=> Nat n | Index of column to keep. |
-> Sources fs | Sources of complete rows. |
-> IO (Sources (Select' n fs)) | Sources of selected column. |
Select a single column from a flow of rows of fields.
:: (Select n (Array fs), Select' n (Array fs) ~ Array (Select' n fs)) | |
=> Nat n | Index of column to keep. |
-> Sinks (Select' n fs) | Sinks for selected column. |
-> IO (Sinks fs) | Sinks for complete rows. |
Select a single column from a flow of fields.
:: (Discard n (Array fs), Discard' n (Array fs) ~ Array (Discard' n fs)) | |
=> Nat n | Index of column to discard. |
-> Sources fs | Sources of complete rows. |
-> IO (Sources (Discard' n fs)) | Sources of partial rows. |
Discard a single column from a flow of fields.
:: (Discard n (Array fs), Discard' n (Array fs) ~ Array (Discard' n fs)) | |
=> Nat n | Index of column to discard. |
-> Sinks (Discard' n fs) | Sinks for partial rows. |
-> IO (Sinks fs) | Sinks for complete rows. |
Discard a single column from a flow of fields.
:: (Mask ms (Array fs), Mask' ms (Array fs) ~ Array (Mask' ms fs)) | |
=> ms | Column mask. |
-> Sources fs | Sources of complete rows. |
-> IO (Sources (Mask' ms fs)) | Sources of masked rows. |
Mask columns from a flow of fields.
:: (Mask ms (Array fs), Mask' ms (Array fs) ~ Array (Mask' ms fs)) | |
=> ms | Column mask. |
-> Sinks (Mask' ms fs) | Sources of complete rows. |
-> IO (Sinks fs) | Sources of masked rows. |
Mask columns from a flow of fields.
Grouping
:: (GroupsDict a, Eq a) | |
=> Sources a | Input elements. |
-> IO (Sources (a, Int)) | Starting element and length of groups. |
Scan through some sources to find runs of matching elements, and count the lengths of those runs.
> F.toList1 0 =<< F.groups_i =<< F.fromList 1 "waabbbblle" [('w',1),('a',2),('b',4),('l',2),('e',1)]
:: GroupsDict a | |
=> (a -> a -> Bool) | Fn to check if consecutive elements are in the same group. |
-> Sources a | Input elements. |
-> IO (Sources (a, Int)) | Starting element and length of groups. |
Like groupsBy
, but take a function to determine whether two consecutive
values should be in the same group.
type GroupsDict a = GroupsDict Int IO A A A a Source
Dictionaries needed to perform a grouping.
Folding
Complete
:: (Flow b, Build a) | |
=> (a -> b -> a) | Combining funtion. |
-> a | Starting value. |
-> Sources b | Input elements to fold. |
-> IO (Array A a) |
Fold all the elements of each stream in a bundle, one stream after the other, returning an array of fold results.
:: Flow b | |
=> (a -> b -> a) | Combining funtion. |
-> a | Starting value. |
-> Sources b | Input elements to fold. |
-> IO a |
Fold all the elements of each stream in a bundle, one stream after the other, returning an array of fold results.
Segmented
:: FoldsDict n a b | |
=> (a -> b -> b) | Worker function. |
-> b | Initial state when folding each segment. |
-> Sources (n, Int) | Segment lengths. |
-> Sources a | Input elements to fold. |
-> IO (Sources (n, b)) | Result elements. |
Given streams of lengths and values, perform a segmented fold where fold segments of values of the corresponding lengths are folded together.
> sSegs <- F.fromList 1 [('a', 1), ('b', 2), ('c', 4), ('d', 0), ('e', 1), ('f', 5 :: Int)] > sVals <- F.fromList 1 [10, 20, 30, 40, 50, 60, 70, 80, 90 :: Int] > F.toList1 0 =<< F.folds_i (+) 0 sSegs sVals [('a',10),('b',50),('c',220),('d',0),('e',80)]
If not enough input elements are available to fold a complete segment then no output is produced for that segment. However, trailing zero length segments still produce the initial value for the fold.
> sSegs <- F.fromList 1 [('a', 1), ('b', 2), ('c', 0), ('d', 0), ('e', 0 :: Int)] > sVals <- F.fromList 1 [10, 20, 30 :: Int] > F.toList1 0 =<< F.folds_i (*) 1 sSegs sVals [('a',10),('b',600),('c',1),('d',1),('e',1)]
type FoldsDict n a b = FoldsDict Int IO A A A A n a b Source
Dictionaries needed to perform a segmented fold.
:: FoldGroupsDict n a b | |
=> (n -> n -> Bool) | Fn to check if consecutive elements are in the same group. |
-> (a -> b -> b) | Worker function for the fold. |
-> b | Initial when folding each segment. |
-> Sources n | Names that determine groups. |
-> Sources a | Values to fold. |
-> IO (Sources (n, b)) |
Combination of groupsBy_i
and folds_i
. We determine the the segment
lengths while performing the folds.
Note that a SQL-like groupby aggregations can be performed using this function, provided the data is pre-sorted on the group key. For example, we can take the average of some groups of values:
> sKeys <- F.fromList 1 "waaaabllle" > sVals <- F.fromList 1 [10, 20, 30, 40, 50, 60, 70, 80, 90, 100 :: Double] > sResult <- F.map_i (\(key, (acc, n)) -> (key, acc / n)) =<< F.foldGroupsBy_i (==) (\x (acc, n) -> (acc + x, n + 1)) (0, 0) sKeys sVals > F.toList1 0 sResult [10.0,35.0,60.0,80.0,100.0]
Finalizers
finalize_i :: (Int -> IO ()) -> Sources a -> IO (Sources a) Source
Attach a finalizer to some sources.
- For a given source, the finalizer will be called the first time a consumer of that source tries to pull an element when no more are available.
- The finalizer is given the index of the source that ended.
- The finalizer will be run after any finalizers already attached to the source.
finalize_o :: (Int -> IO ()) -> Sinks a -> IO (Sinks a) Source
Attach a finalizer to some sinks.
- For a given sink, the finalizer will be called the first time that sink is ejected.
- The finalizer is given the index of the sink that was ejected.
- The finalizer will be run after any finalizers already attached to the sink.