rio-0.1.22.0: A standard library for Haskell
Safe HaskellNone
LanguageHaskell2010

RIO.Vector.Unboxed.Partial

Description

Unboxed Vector partial functions. Import as:

import qualified RIO.Vector.Unboxed.Partial as VU'
Synopsis

Accessors

Indexing

(!) :: Unbox a => Vector a -> Int -> a #

O(1) Indexing.

head :: Unbox a => Vector a -> a #

O(1) First element.

last :: Unbox a => Vector a -> a #

O(1) Last element.

Monadic indexing

indexM :: (Unbox a, Monad m) => Vector a -> Int -> m a #

O(1) Indexing in a monad.

The monad allows operations to be strict in the vector when necessary. Suppose vector copying is implemented like this:

copy mv v = ... write mv i (v ! i) ...

For lazy vectors, v ! i would not be evaluated which means that mv would unnecessarily retain a reference to v in each element written.

With indexM, copying can be implemented like this instead:

copy mv v = ... do
                  x <- indexM v i
                  write mv i x

Here, no references to v are retained because indexing (but not the element) is evaluated eagerly.

headM :: (Unbox a, Monad m) => Vector a -> m a #

O(1) First element of a vector in a monad. See indexM for an explanation of why this is useful.

lastM :: (Unbox a, Monad m) => Vector a -> m a #

O(1) Last element of a vector in a monad. See indexM for an explanation of why this is useful.

Extracting subvectors

init :: Unbox a => Vector a -> Vector a #

O(1) Yield all but the last element without copying. The vector may not be empty.

tail :: Unbox a => Vector a -> Vector a #

O(1) Yield all but the first element without copying. The vector may not be empty.

Modifying vectors

Bulk updates

(//) #

Arguments

:: Unbox a 
=> Vector a

initial vector (of length m)

-> [(Int, a)]

list of index/value pairs (of length n)

-> Vector a 

O(m+n) For each pair (i,a) from the list of idnex/value pairs, replace the vector element at position i by a.

<5,9,2,7> // [(2,1),(0,3),(2,8)] = <3,9,8,7>

update #

Arguments

:: Unbox a 
=> Vector a

initial vector (of length m)

-> Vector (Int, a)

vector of index/value pairs (of length n)

-> Vector a 

O(m+n) For each pair (i,a) from the vector of index/value pairs, replace the vector element at position i by a.

update <5,9,2,7> <(2,1),(0,3),(2,8)> = <3,9,8,7>

update_ #

Arguments

:: Unbox a 
=> Vector a

initial vector (of length m)

-> Vector Int

index vector (of length n1)

-> Vector a

value vector (of length n2)

-> Vector a 

O(m+min(n1,n2)) For each index i from the index vector and the corresponding value a from the value vector, replace the element of the initial vector at position i by a.

update_ <5,9,2,7>  <2,0,2> <1,3,8> = <3,9,8,7>

The function update provides the same functionality and is usually more convenient.

update_ xs is ys = update xs (zip is ys)

Accumulations

accum #

Arguments

:: Unbox a 
=> (a -> b -> a)

accumulating function f

-> Vector a

initial vector (of length m)

-> [(Int, b)]

list of index/value pairs (of length n)

-> Vector a 

O(m+n) For each pair (i,b) from the list, replace the vector element a at position i by f a b.

Examples

Expand
>>> import qualified Data.Vector.Unboxed as VU
>>> VU.accum (+) (VU.fromList [1000,2000,3000 :: Int]) [(2,4),(1,6),(0,3),(1,10)]
[1003,2016,3004]

accumulate #

Arguments

:: (Unbox a, Unbox b) 
=> (a -> b -> a)

accumulating function f

-> Vector a

initial vector (of length m)

-> Vector (Int, b)

vector of index/value pairs (of length n)

-> Vector a 

O(m+n) For each pair (i,b) from the vector of pairs, replace the vector element a at position i by f a b.

Examples

Expand
>>> import qualified Data.Vector.Unboxed as VU
>>> VU.accumulate (+) (VU.fromList [1000,2000,3000 :: Int]) (VU.fromList [(2,4),(1,6),(0,3),(1,10)])
[1003,2016,3004]

accumulate_ #

Arguments

:: (Unbox a, Unbox b) 
=> (a -> b -> a)

accumulating function f

-> Vector a

initial vector (of length m)

-> Vector Int

index vector (of length n1)

-> Vector b

value vector (of length n2)

-> Vector a 

O(m+min(n1,n2)) For each index i from the index vector and the corresponding value b from the the value vector, replace the element of the initial vector at position i by f a b.

accumulate_ (+) <5,9,2> <2,1,0,1> <4,6,3,7> = <5+3, 9+6+7, 2+4>

The function accumulate provides the same functionality and is usually more convenient.

accumulate_ f as is bs = accumulate f as (zip is bs)

Permutations

backpermute :: Unbox a => Vector a -> Vector Int -> Vector a #

O(n) Yield the vector obtained by replacing each element i of the index vector by xs!i. This is equivalent to map (xs!) is, but is often much more efficient.

backpermute <a,b,c,d> <0,3,2,3,1,0> = <a,d,c,d,b,a>

Folding

foldl1 :: Unbox a => (a -> a -> a) -> Vector a -> a #

O(n) Left fold on non-empty vectors.

foldl1' :: Unbox a => (a -> a -> a) -> Vector a -> a #

O(n) Left fold on non-empty vectors with strict accumulator.

foldr1 :: Unbox a => (a -> a -> a) -> Vector a -> a #

O(n) Right fold on non-empty vectors.

foldr1' :: Unbox a => (a -> a -> a) -> Vector a -> a #

O(n) Right fold on non-empty vectors with strict accumulator.

Specialised folds

maximum :: (Unbox a, Ord a) => Vector a -> a #

O(n) Yield the maximum element of the vector. The vector may not be empty. In case of a tie, the first occurrence wins.

Examples

Expand
>>> import qualified Data.Vector.Unboxed as VU
>>> VU.maximum $ VU.fromList [2, 1 :: Int]
2
>>> import Data.Semigroup
>>> VU.maximum $ VU.fromList [Arg 1 'a', Arg (2 :: Int) 'b']
Arg 2 'b'
>>> VU.maximum $ VU.fromList [Arg 1 'a', Arg (1 :: Int) 'b']
Arg 1 'a'

maximumBy :: Unbox a => (a -> a -> Ordering) -> Vector a -> a #

O(n) Yield the maximum element of the vector according to the given comparison function. The vector may not be empty. In case of a tie, the first occurrence wins. This behavior is different from maximumBy which returns the last tie.

Examples

Expand
>>> import Data.Ord
>>> import qualified Data.Vector.Unboxed as VU
>>> VU.maximumBy (comparing fst) $ VU.fromList [(2,'a'), (1 :: Int,'b')]
(2,'a')
>>> VU.maximumBy (comparing fst) $ VU.fromList [(1,'a'), (1 :: Int,'b')]
(1,'a')

minimum :: (Unbox a, Ord a) => Vector a -> a #

O(n) Yield the minimum element of the vector. The vector may not be empty. In case of a tie, the first occurrence wins.

Examples

Expand
>>> import qualified Data.Vector.Unboxed as VU
>>> VU.minimum $ VU.fromList [2, 1 :: Int]
1
>>> import Data.Semigroup
>>> VU.minimum $ VU.fromList [Arg 2 'a', Arg (1 :: Int) 'b']
Arg 1 'b'
>>> VU.minimum $ VU.fromList [Arg 1 'a', Arg (1 :: Int) 'b']
Arg 1 'a'

minimumBy :: Unbox a => (a -> a -> Ordering) -> Vector a -> a #

O(n) Yield the minimum element of the vector according to the given comparison function. The vector may not be empty. In case of a tie, the first occurrence wins.

Examples

Expand
>>> import Data.Ord
>>> import qualified Data.Vector.Unboxed as VU
>>> VU.minimumBy (comparing fst) $ VU.fromList [(2,'a'), (1 :: Int,'b')]
(1,'b')
>>> VU.minimumBy (comparing fst) $ VU.fromList [(1,'a'), (1 :: Int,'b')]
(1,'a')

O(n) Yield the minimum element of the vector according to the given comparison function. The vector may not be empty.

minIndex :: (Unbox a, Ord a) => Vector a -> Int #

O(n) Yield the index of the minimum element of the vector. The vector may not be empty.

minIndexBy :: Unbox a => (a -> a -> Ordering) -> Vector a -> Int #

O(n) Yield the index of the minimum element of the vector according to the given comparison function. The vector may not be empty.

Examples

Expand
>>> import Data.Ord
>>> import qualified Data.Vector.Unboxed as VU
>>> VU.minIndexBy (comparing fst) $ VU.fromList [(2,'a'), (1,'b')]
1
>>> VU.minIndexBy (comparing fst) $ VU.fromList [(1,'a'), (1,'b')]
0

maxIndex :: (Unbox a, Ord a) => Vector a -> Int #

O(n) Yield the index of the maximum element of the vector. The vector may not be empty.

maxIndexBy :: Unbox a => (a -> a -> Ordering) -> Vector a -> Int #

O(n) Yield the index of the maximum element of the vector according to the given comparison function. The vector may not be empty. In case of a tie, the first occurrence wins.

Examples

Expand
>>> import Data.Ord
>>> import qualified Data.Vector.Unboxed as VU
>>> VU.maxIndexBy (comparing fst) $ VU.fromList [(2,'a'), (1,'b')]
0
>>> VU.maxIndexBy (comparing fst) $ VU.fromList [(1,'a'), (1,'b')]
0

Monadic folds

fold1M :: (Monad m, Unbox a) => (a -> a -> m a) -> Vector a -> m a #

O(n) Monadic fold over non-empty vectors.

fold1M' :: (Monad m, Unbox a) => (a -> a -> m a) -> Vector a -> m a #

O(n) Monadic fold over non-empty vectors with strict accumulator.

fold1M_ :: (Monad m, Unbox a) => (a -> a -> m a) -> Vector a -> m () #

O(n) Monadic fold over non-empty vectors that discards the result.

fold1M'_ :: (Monad m, Unbox a) => (a -> a -> m a) -> Vector a -> m () #

O(n) Monadic fold over non-empty vectors with strict accumulator that discards the result.

Prefix sums (scans)

scanl1 :: Unbox a => (a -> a -> a) -> Vector a -> Vector a #

O(n) Initial-value free left-to-right scan over a vector.

scanl f <x1,...,xn> = <y1,...,yn>
  where y1 = x1
        yi = f y(i-1) xi

Note: Since 0.13, application of this to an empty vector no longer results in an error; instead it produces an empty vector.

Examples

Expand
>>> import qualified Data.Vector.Unboxed as VU
>>> VU.scanl1 min $ VU.fromListN 5 [4,2,4,1,3 :: Int]
[4,2,2,1,1]
>>> VU.scanl1 max $ VU.fromListN 5 [1,3,2,5,4 :: Int]
[1,3,3,5,5]
>>> VU.scanl1 min (VU.empty :: VU.Vector Int)
[]

scanl1' :: Unbox a => (a -> a -> a) -> Vector a -> Vector a #

O(n) Initial-value free left-to-right scan over a vector with a strict accumulator.

Note: Since 0.13, application of this to an empty vector no longer results in an error; instead it produces an empty vector.

Examples

Expand
>>> import qualified Data.Vector.Unboxed as VU
>>> VU.scanl1' min $ VU.fromListN 5 [4,2,4,1,3 :: Int]
[4,2,2,1,1]
>>> VU.scanl1' max $ VU.fromListN 5 [1,3,2,5,4 :: Int]
[1,3,3,5,5]
>>> VU.scanl1' min (VU.empty :: VU.Vector Int)
[]

scanr1 :: Unbox a => (a -> a -> a) -> Vector a -> Vector a #

O(n) Right-to-left, initial-value free scan over a vector.

Note: Since 0.13, application of this to an empty vector no longer results in an error; instead it produces an empty vector.

Examples

Expand
>>> import qualified Data.Vector.Unboxed as VU
>>> VU.scanr1 min $ VU.fromListN 5 [3,1,4,2,4 :: Int]
[1,1,2,2,4]
>>> VU.scanr1 max $ VU.fromListN 5 [4,5,2,3,1 :: Int]
[5,5,3,3,1]
>>> VU.scanr1 min (VU.empty :: VU.Vector Int)
[]

scanr1' :: Unbox a => (a -> a -> a) -> Vector a -> Vector a #

O(n) Right-to-left, initial-value free scan over a vector with a strict accumulator.

Note: Since 0.13, application of this to an empty vector no longer results in an error; instead it produces an empty vector.

Examples

Expand
>>> import qualified Data.Vector.Unboxed as VU
>>> VU.scanr1' min $ VU.fromListN 5 [3,1,4,2,4 :: Int]
[1,1,2,2,4]
>>> VU.scanr1' max $ VU.fromListN 5 [4,5,2,3,1 :: Int]
[5,5,3,3,1]
>>> VU.scanr1' min (VU.empty :: VU.Vector Int)
[]