rio-0.1.22.0: A standard library for Haskell

Safe Haskell | Safe-Inferred
Language | Haskell2010

RIO.Vector.Boxed

Contents

- Boxed vectors
- Accessors
  - Length information
  - Indexing
  - Extracting subvectors
- Construction
  - Initialisation
  - Monadic initialisation
  - Unfolding
  - Enumeration
  - Concatenation
  - Restricting memory usage
- Modifying vectors
  - Permutations
  - Safe destructive update
- Elementwise operations
  - Indexing
  - Mapping
  - Monadic mapping
  - Zipping
  - Monadic zipping
  - Unzipping
- Working with predicates
  - Filtering
  - Partitioning
  - Searching
- Folding
  - Specialised folds
  - Monadic folds
  - Monadic sequencing
- Prefix sums (scans)
- Conversions
  - Lists
  - Different vector types
  - Mutable vectors

Description

Boxed `Vector`. Import as:

    import qualified RIO.Vector.Boxed as VB

This module does not export any partial or unsafe functions. For those, see RIO.Vector.Boxed.Partial and RIO.Vector.Boxed.Unsafe

Synopsis

- data Vector a
- data MVector s a
- length :: Vector a -> Int
- null :: Vector a -> Bool
- (!?) :: Vector a -> Int -> Maybe a
- slice :: Int -> Int -> Vector a -> Vector a
- take :: Int -> Vector a -> Vector a
- drop :: Int -> Vector a -> Vector a
- splitAt :: Int -> Vector a -> (Vector a, Vector a)
- empty :: Vector a
- singleton :: a -> Vector a
- replicate :: Int -> a -> Vector a
- generate :: Int -> (Int -> a) -> Vector a
- iterateN :: Int -> (a -> a) -> a -> Vector a
- replicateM :: Monad m => Int -> m a -> m (Vector a)
- generateM :: Monad m => Int -> (Int -> m a) -> m (Vector a)
- iterateNM :: Monad m => Int -> (a -> m a) -> a -> m (Vector a)
- create :: (forall s. ST s (MVector s a)) -> Vector a
- createT :: Traversable f => (forall s. ST s (f (MVector s a))) -> f (Vector a)
- unfoldr :: (b -> Maybe (a, b)) -> b -> Vector a
- unfoldrN :: Int -> (b -> Maybe (a, b)) -> b -> Vector a
- unfoldrM :: Monad m => (b -> m (Maybe (a, b))) -> b -> m (Vector a)
- unfoldrNM :: Monad m => Int -> (b -> m (Maybe (a, b))) -> b -> m (Vector a)
- constructN :: Int -> (Vector a -> a) -> Vector a
- constructrN :: Int -> (Vector a -> a) -> Vector a
- enumFromN :: Num a => a -> Int -> Vector a
- enumFromStepN :: Num a => a -> a -> Int -> Vector a
- enumFromTo :: Enum a => a -> a -> Vector a
- enumFromThenTo :: Enum a => a -> a -> a -> Vector a
- cons :: a -> Vector a -> Vector a
- snoc :: Vector a -> a -> Vector a
- (++) :: Vector a -> Vector a -> Vector a
- concat :: [Vector a] -> Vector a
- force :: Vector a -> Vector a
- reverse :: Vector a -> Vector a
- modify :: (forall s. MVector s a -> ST s ()) -> Vector a -> Vector a
- indexed :: Vector a -> Vector (Int, a)
- map :: (a -> b) -> Vector a -> Vector b
- imap :: (Int -> a -> b) -> Vector a -> Vector b
- concatMap :: (a -> Vector b) -> Vector a -> Vector b
- mapM :: Monad m => (a -> m b) -> Vector a -> m (Vector b)
- imapM :: Monad m => (Int -> a -> m b) -> Vector a -> m (Vector b)
- mapM_ :: Monad m => (a -> m b) -> Vector a -> m ()
- imapM_ :: Monad m => (Int -> a -> m b) -> Vector a -> m ()
- forM :: Monad m => Vector a -> (a -> m b) -> m (Vector b)
- forM_ :: Monad m => Vector a -> (a -> m b) -> m ()
- zipWith :: (a -> b -> c) -> Vector a -> Vector b -> Vector c
- zipWith3 :: (a -> b -> c -> d) -> Vector a -> Vector b -> Vector c -> Vector d
- zipWith4 :: (a -> b -> c -> d -> e) -> Vector a -> Vector b -> Vector c -> Vector d -> Vector e
- zipWith5 :: (a -> b -> c -> d -> e -> f) -> Vector a -> Vector b -> Vector c -> Vector d -> Vector e -> Vector f
- zipWith6 :: (a -> b -> c -> d -> e -> f -> g) -> Vector a -> Vector b -> Vector c -> Vector d -> Vector e -> Vector f -> Vector g
- izipWith :: (Int -> a -> b -> c) -> Vector a -> Vector b -> Vector c
- izipWith3 :: (Int -> a -> b -> c -> d) -> Vector a -> Vector b -> Vector c -> Vector d
- izipWith4 :: (Int -> a -> b -> c -> d -> e) -> Vector a -> Vector b -> Vector c -> Vector d -> Vector e
- izipWith5 :: (Int -> a -> b -> c -> d -> e -> f) -> Vector a -> Vector b -> Vector c -> Vector d -> Vector e -> Vector f
- izipWith6 :: (Int -> a -> b -> c -> d -> e -> f -> g) -> Vector a -> Vector b -> Vector c -> Vector d -> Vector e -> Vector f -> Vector g
- zip :: Vector a -> Vector b -> Vector (a, b)
- zip3 :: Vector a -> Vector b -> Vector c -> Vector (a, b, c)
- zip4 :: Vector a -> Vector b -> Vector c -> Vector d -> Vector (a, b, c, d)
- zip5 :: Vector a -> Vector b -> Vector c -> Vector d -> Vector e -> Vector (a, b, c, d, e)
- zip6 :: Vector a -> Vector b -> Vector c -> Vector d -> Vector e -> Vector f -> Vector (a, b, c, d, e, f)
- zipWithM :: Monad m => (a -> b -> m c) -> Vector a -> Vector b -> m (Vector c)
- izipWithM :: Monad m => (Int -> a -> b -> m c) -> Vector a -> Vector b -> m (Vector c)
- zipWithM_ :: Monad m => (a -> b -> m c) -> Vector a -> Vector b -> m ()
- izipWithM_ :: Monad m => (Int -> a -> b -> m c) -> Vector a -> Vector b -> m ()
- unzip :: Vector (a, b) -> (Vector a, Vector b)
- unzip3 :: Vector (a, b, c) -> (Vector a, Vector b, Vector c)
- unzip4 :: Vector (a, b, c, d) -> (Vector a, Vector b, Vector c, Vector d)
- unzip5 :: Vector (a, b, c, d, e) -> (Vector a, Vector b, Vector c, Vector d, Vector e)
- unzip6 :: Vector (a, b, c, d, e, f) -> (Vector a, Vector b, Vector c, Vector d, Vector e, Vector f)
- filter :: (a -> Bool) -> Vector a -> Vector a
- ifilter :: (Int -> a -> Bool) -> Vector a -> Vector a
- uniq :: Eq a => Vector a -> Vector a
- mapMaybe :: (a -> Maybe b) -> Vector a -> Vector b
- imapMaybe :: (Int -> a -> Maybe b) -> Vector a -> Vector b
- filterM :: Monad m => (a -> m Bool) -> Vector a -> m (Vector a)
- takeWhile :: (a -> Bool) -> Vector a -> Vector a
- dropWhile :: (a -> Bool) -> Vector a -> Vector a
- partition :: (a -> Bool) -> Vector a -> (Vector a, Vector a)
- unstablePartition :: (a -> Bool) -> Vector a -> (Vector a, Vector a)
- span :: (a -> Bool) -> Vector a -> (Vector a, Vector a)
- break :: (a -> Bool) -> Vector a -> (Vector a, Vector a)
- elem :: Eq a => a -> Vector a -> Bool
- notElem :: Eq a => a -> Vector a -> Bool
- find :: (a -> Bool) -> Vector a -> Maybe a
- findIndex :: (a -> Bool) -> Vector a -> Maybe Int
- findIndices :: (a -> Bool) -> Vector a -> Vector Int
- elemIndex :: Eq a => a -> Vector a -> Maybe Int
- elemIndices :: Eq a => a -> Vector a -> Vector Int
- foldl :: (a -> b -> a) -> a -> Vector b -> a
- foldl' :: (a -> b -> a) -> a -> Vector b -> a
- foldr :: (a -> b -> b) -> b -> Vector a -> b
- foldr' :: (a -> b -> b) -> b -> Vector a -> b
- ifoldl :: (a -> Int -> b -> a) -> a -> Vector b -> a
- ifoldl' :: (a -> Int -> b -> a) -> a -> Vector b -> a
- ifoldr :: (Int -> a -> b -> b) -> b -> Vector a -> b
- ifoldr' :: (Int -> a -> b -> b) -> b -> Vector a -> b
- all :: (a -> Bool) -> Vector a -> Bool
- any :: (a -> Bool) -> Vector a -> Bool
- and :: Vector Bool -> Bool
- or :: Vector Bool -> Bool
- sum :: Num a => Vector a -> a
- product :: Num a => Vector a -> a
- foldM :: Monad m => (a -> b -> m a) -> a -> Vector b -> m a
- ifoldM :: Monad m => (a -> Int -> b -> m a) -> a -> Vector b -> m a
- foldM' :: Monad m => (a -> b -> m a) -> a -> Vector b -> m a
- ifoldM' :: Monad m => (a -> Int -> b -> m a) -> a -> Vector b -> m a
- foldM_ :: Monad m => (a -> b -> m a) -> a -> Vector b -> m ()
- ifoldM_ :: Monad m => (a -> Int -> b -> m a) -> a -> Vector b -> m ()
- foldM'_ :: Monad m => (a -> b -> m a) -> a -> Vector b -> m ()
- ifoldM'_ :: Monad m => (a -> Int -> b -> m a) -> a -> Vector b -> m ()
- sequence :: Monad m => Vector (m a) -> m (Vector a)
- sequence_ :: Monad m => Vector (m a) -> m ()
- prescanl :: (a -> b -> a) -> a -> Vector b -> Vector a
- prescanl' :: (a -> b -> a) -> a -> Vector b -> Vector a
- postscanl :: (a -> b -> a) -> a -> Vector b -> Vector a
- postscanl' :: (a -> b -> a) -> a -> Vector b -> Vector a
- scanl :: (a -> b -> a) -> a -> Vector b -> Vector a
- scanl' :: (a -> b -> a) -> a -> Vector b -> Vector a
- iscanl :: (Int -> a -> b -> a) -> a -> Vector b -> Vector a
- iscanl' :: (Int -> a -> b -> a) -> a -> Vector b -> Vector a
- prescanr :: (a -> b -> b) -> b -> Vector a -> Vector b
- prescanr' :: (a -> b -> b) -> b -> Vector a -> Vector b
- postscanr :: (a -> b -> b) -> b -> Vector a -> Vector b
- postscanr' :: (a -> b -> b) -> b -> Vector a -> Vector b
- scanr :: (a -> b -> b) -> b -> Vector a -> Vector b
- scanr' :: (a -> b -> b) -> b -> Vector a -> Vector b
- iscanr :: (Int -> a -> b -> b) -> b -> Vector a -> Vector b
- iscanr' :: (Int -> a -> b -> b) -> b -> Vector a -> Vector b
- toList :: Vector a -> [a]
- fromList :: [a] -> Vector a
- fromListN :: Int -> [a] -> Vector a
- convert :: (Vector v a, Vector w a) => v a -> w a
- freeze :: PrimMonad m => MVector (PrimState m) a -> m (Vector a)
- thaw :: PrimMonad m => Vector a -> m (MVector (PrimState m) a)
- copy :: PrimMonad m => MVector (PrimState m) a -> Vector a -> m ()

# Boxed vectors

data Vector a #

Boxed vectors, supporting efficient slicing.

#### Instances

Instances details

MonadFail Vector | Since: vector-0.12.1.0
Instance details Defined in Data.Vector Methods fail :: String -> Vector a #
MonadFix Vector | This instance has the same semantics as the one for lists. Since: vector-0.12.2.0
Instance details Defined in Data.Vector Methods mfix :: (a -> Vector a) -> Vector a
MonadZip Vector |
Instance details Defined in Data.Vector Methods mzip :: Vector a -> Vector b -> Vector (a, b) mzipWith :: (a -> b -> c) -> Vector a -> Vector b -> Vector c munzip :: Vector (a, b) -> (Vector a, Vector b)
Foldable Vector |

Instance details

Defined in Data.Vector

Methods

fold :: Monoid m => Vector m -> m #

foldMap :: Monoid m => (a -> m) -> Vector a -> m #

foldMap' :: Monoid m => (a -> m) -> Vector a -> m

foldr :: (a -> b -> b) -> b -> Vector a -> b #

foldr' :: (a -> b -> b) -> b -> Vector a -> b

foldl :: (b -> a -> b) -> b -> Vector a -> b #

foldl' :: (b -> a -> b) -> b -> Vector a -> b #

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

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

toList :: Vector a -> [a] #

null :: Vector a -> Bool #

length :: Vector a -> Int #

elem :: Eq a => a -> Vector a -> Bool #

maximum :: Ord a => Vector a -> a #

minimum :: Ord a => Vector a -> a #

sum :: Num a => Vector a -> a #

product :: Num a => Vector a -> a #

Eq1 Vector |
Instance details Defined in Data.Vector Methods liftEq :: (a -> b -> Bool) -> Vector a -> Vector b -> Bool
Ord1 Vector |
Instance details Defined in Data.Vector Methods liftCompare :: (a -> b -> Ordering) -> Vector a -> Vector b -> Ordering
Read1 Vector |
Instance details Defined in Data.Vector Methods liftReadsPrec :: (Int -> ReadS a) -> ReadS [a] -> Int -> ReadS (Vector a) liftReadList :: (Int -> ReadS a) -> ReadS [a] -> ReadS [Vector a] liftReadPrec :: ReadPrec a -> ReadPrec [a] -> ReadPrec (Vector a) liftReadListPrec :: ReadPrec a -> ReadPrec [a] -> ReadPrec [Vector a]
Show1 Vector |
Instance details Defined in Data.Vector Methods liftShowsPrec :: (Int -> a -> ShowS) -> ([a] -> ShowS) -> Int -> Vector a -> ShowS liftShowList :: (Int -> a -> ShowS) -> ([a] -> ShowS) -> [Vector a] -> ShowS
Traversable Vector |
Instance details Defined in Data.Vector Methods traverse :: Applicative f => (a -> f b) -> Vector a -> f (Vector b) # sequenceA :: Applicative f => Vector (f a) -> f (Vector a) # mapM :: Monad m => (a -> m b) -> Vector a -> m (Vector b) # sequence :: Monad m => Vector (m a) -> m (Vector a) #
Alternative Vector |
Instance details Defined in Data.Vector Methods empty :: Vector a (<|>) :: Vector a -> Vector a -> Vector a # some :: Vector a -> Vector [a] # many :: Vector a -> Vector [a] #
Applicative Vector |
Instance details Defined in Data.Vector Methods pure :: a -> Vector a # (<*>) :: Vector (a -> b) -> Vector a -> Vector b # liftA2 :: (a -> b -> c) -> Vector a -> Vector b -> Vector c # (*>) :: Vector a -> Vector b -> Vector b # (<*) :: Vector a -> Vector b -> Vector a #
Functor Vector |
Instance details Defined in Data.Vector Methods fmap :: (a -> b) -> Vector a -> Vector b # (<$) :: a -> Vector b -> Vector a #
Monad Vector |
Instance details Defined in Data.Vector Methods (>>=) :: Vector a -> (a -> Vector b) -> Vector b # (>>) :: Vector a -> Vector b -> Vector b # return :: a -> Vector a #
MonadPlus Vector |
Instance details Defined in Data.Vector Methods mzero :: Vector a # mplus :: Vector a -> Vector a -> Vector a #
NFData1 Vector | Since: vector-0.12.1.0
Instance details Defined in Data.Vector Methods liftRnf :: (a -> ()) -> Vector a -> ()
Vector Vector a |

Instance details

Defined in Data.Vector

Methods

basicUnsafeFreeze :: Mutable Vector s a -> ST s (Vector a) #

basicUnsafeThaw :: Vector a -> ST s (Mutable Vector s a) #

basicLength :: Vector a -> Int #

basicUnsafeSlice :: Int -> Int -> Vector a -> Vector a #

basicUnsafeIndexM :: Vector a -> Int -> Box a #

basicUnsafeCopy :: Mutable Vector s a -> Vector a -> ST s () #

elemseq :: Vector a -> a -> b -> b #

Data a => Data (Vector a) |

Instance details

Defined in Data.Vector

Methods

gfoldl :: (forall d b. Data d => c (d -> b) -> d -> c b) -> (forall g. g -> c g) -> Vector a -> c (Vector a) #

gunfold :: (forall b r. Data b => c (b -> r) -> c r) -> (forall r. r -> c r) -> Constr -> c (Vector a) #

toConstr :: Vector a -> Constr #

dataTypeOf :: Vector a -> DataType #

dataCast1 :: Typeable t => (forall d. Data d => c (t d)) -> Maybe (c (Vector a)) #

dataCast2 :: Typeable t => (forall d e. (Data d, Data e) => c (t d e)) -> Maybe (c (Vector a)) #

gmapT :: (forall b. Data b => b -> b) -> Vector a -> Vector a #

gmapQl :: (r -> r' -> r) -> r -> (forall d. Data d => d -> r') -> Vector a -> r #

gmapQr :: forall r r'. (r' -> r -> r) -> r -> (forall d. Data d => d -> r') -> Vector a -> r #

gmapQ :: (forall d. Data d => d -> u) -> Vector a -> [u] #

gmapQi :: Int -> (forall d. Data d => d -> u) -> Vector a -> u #

gmapM :: Monad m => (forall d. Data d => d -> m d) -> Vector a -> m (Vector a) #

gmapMp :: MonadPlus m => (forall d. Data d => d -> m d) -> Vector a -> m (Vector a) #

gmapMo :: MonadPlus m => (forall d. Data d => d -> m d) -> Vector a -> m (Vector a) #

Monoid (Vector a) |
Instance details Defined in Data.Vector Methods mempty :: Vector a # mappend :: Vector a -> Vector a -> Vector a # mconcat :: [Vector a] -> Vector a #
Semigroup (Vector a) |
Instance details Defined in Data.Vector Methods (<>) :: Vector a -> Vector a -> Vector a # sconcat :: NonEmpty (Vector a) -> Vector a stimes :: Integral b => b -> Vector a -> Vector a
IsList (Vector a) |
Instance details Defined in Data.Vector Associated Types type Item (Vector a) Methods fromList :: [Item (Vector a)] -> Vector a fromListN :: Int -> [Item (Vector a)] -> Vector a toList :: Vector a -> [Item (Vector a)]
Read a => Read (Vector a) |
Instance details Defined in Data.Vector Methods readsPrec :: Int -> ReadS (Vector a) readList :: ReadS [Vector a] readPrec :: ReadPrec (Vector a) readListPrec :: ReadPrec [Vector a]
Show a => Show (Vector a) |
Instance details Defined in Data.Vector Methods showsPrec :: Int -> Vector a -> ShowS show :: Vector a -> String # showList :: [Vector a] -> ShowS
NFData a => NFData (Vector a) |
Instance details Defined in Data.Vector Methods rnf :: Vector a -> () #
Eq a => Eq (Vector a) |
Instance details Defined in Data.Vector Methods (==) :: Vector a -> Vector a -> Bool # (/=) :: Vector a -> Vector a -> Bool #
Ord a => Ord (Vector a) |
Instance details Defined in Data.Vector Methods compare :: Vector a -> Vector a -> Ordering # (<) :: Vector a -> Vector a -> Bool # (<=) :: Vector a -> Vector a -> Bool # (>) :: Vector a -> Vector a -> Bool # (>=) :: Vector a -> Vector a -> Bool # max :: Vector a -> Vector a -> Vector a # min :: Vector a -> Vector a -> Vector a #
type Mutable Vector |
Instance details Defined in Data.Vector type Mutable Vector = MVector
type Item (Vector a) |
Instance details Defined in Data.Vector type Item (Vector a) = a

data MVector s a #

Mutable boxed vectors keyed on the monad they live in (`IO` or ``ST` s`).

#### Instances

Instances details

MVector MVector a |

Instance details

Defined in Data.Vector.Mutable

Methods

basicLength :: MVector s a -> Int #

basicUnsafeSlice :: Int -> Int -> MVector s a -> MVector s a #

basicOverlaps :: MVector s a -> MVector s a -> Bool #

basicUnsafeNew :: Int -> ST s (MVector s a) #

basicInitialize :: MVector s a -> ST s () #

basicUnsafeReplicate :: Int -> a -> ST s (MVector s a) #

basicUnsafeRead :: MVector s a -> Int -> ST s a #

basicUnsafeWrite :: MVector s a -> Int -> a -> ST s () #

basicClear :: MVector s a -> ST s () #

basicSet :: MVector s a -> a -> ST s () #

basicUnsafeCopy :: MVector s a -> MVector s a -> ST s () #

basicUnsafeMove :: MVector s a -> MVector s a -> ST s () #

basicUnsafeGrow :: MVector s a -> Int -> ST s (MVector s a) #

# Accessors

## Length information

length :: Vector a -> Int #

O(1) Yield the length of the vector.

null :: Vector a -> Bool #

O(1) Test whether a vector is empty.

## Indexing

(!?) :: Vector a -> Int -> Maybe a #

O(1) Safe indexing.

## Extracting subvectors

slice #

Arguments

:: Int | `i` starting index
-> Int | `n` length
-> Vector a |
-> Vector a |

O(1) Yield a slice of the vector without copying it. The vector must contain at least `i+n` elements.

take :: Int -> Vector a -> Vector a #

O(1) Yield at the first `n` elements without copying. The vector may contain less than `n` elements, in which case it is returned unchanged.

drop :: Int -> Vector a -> Vector a #

O(1) Yield all but the first `n` elements without copying. The vector may contain less than `n` elements, in which case an empty vector is returned.

splitAt :: Int -> Vector a -> (Vector a, Vector a) #

O(1) Yield the first `n` elements paired with the remainder, without copying.

Note that ``splitAt` n v` is equivalent to `(`take` n v, `drop` n v)`, but slightly more efficient.

Since: vector-0.7.1

# Construction

## Initialisation

empty :: Vector a #

O(1) The empty vector.

singleton :: a -> Vector a #

O(1) A vector with exactly one element.

replicate :: Int -> a -> Vector a #

O(n) A vector of the given length with the same value in each position.

generate :: Int -> (Int -> a) -> Vector a #

O(n) Construct a vector of the given length by applying the function to each index.

iterateN :: Int -> (a -> a) -> a -> Vector a #

O(n) Apply the function \(\max(n - 1, 0)\) times to an initial value, producing a vector of length \(\max(n, 0)\). The 0th element will contain the initial value, which is why there is one less function application than the number of elements in the produced vector.

\( \underbrace{x, f (x), f (f (x)), \ldots}_{\max(0,n)\rm{~elements}} \)

### Examples

Expand

    >>> import qualified Data.Vector as V
    >>> V.iterateN 0 undefined undefined :: V.Vector String
    []
    >>> V.iterateN 4 (\x -> x <> x) "Hi"
    ["Hi","HiHi","HiHiHiHi","HiHiHiHiHiHiHiHi"]

Since: vector-0.7.1

## Monadic initialisation

replicateM :: Monad m => Int -> m a -> m (Vector a) #

O(n) Execute the monadic action the given number of times and store the results in a vector.

generateM :: Monad m => Int -> (Int -> m a) -> m (Vector a) #

O(n) Construct a vector of the given length by applying the monadic action to each index.

iterateNM :: Monad m => Int -> (a -> m a) -> a -> m (Vector a) #

O(n) Apply the monadic function \(\max(n - 1, 0)\) times to an initial value, producing a vector of length \(\max(n, 0)\). The 0th element will contain the initial value, which is why there is one less function application than the number of elements in the produced vector.

For a non-monadic version, see `iterateN`.

Since: vector-0.12.0.0

create :: (forall s. ST s (MVector s a)) -> Vector a #

Execute the monadic action and freeze the resulting vector.

    create (do { v <- new 2; write v 0 'a'; write v 1 'b'; return v }) = <a,b>

createT :: Traversable f => (forall s. ST s (f (MVector s a))) -> f (Vector a) #

Execute the monadic action and freeze the resulting vectors.

## Unfolding

unfoldr :: (b -> Maybe (a, b)) -> b -> Vector a #

O(n) Construct a vector by repeatedly applying the generator function to a seed. The generator function yields `Just` the next element and the new seed or `Nothing` if there are no more elements.

    unfoldr (\n -> if n == 0 then Nothing else Just (n,n-1)) 10
     = <10,9,8,7,6,5,4,3,2,1>

unfoldrN :: Int -> (b -> Maybe (a, b)) -> b -> Vector a #

O(n) Construct a vector with at most `n` elements by repeatedly applying the generator function to a seed. The generator function yields `Just` the next element and the new seed or `Nothing` if there are no more elements.

    unfoldrN 3 (\n -> Just (n,n-1)) 10 = <10,9,8>

unfoldrM :: Monad m => (b -> m (Maybe (a, b))) -> b -> m (Vector a) #

O(n) Construct a vector by repeatedly applying the monadic generator function to a seed. The generator function yields `Just` the next element and the new seed or `Nothing` if there are no more elements.

unfoldrNM :: Monad m => Int -> (b -> m (Maybe (a, b))) -> b -> m (Vector a) #

O(n) Construct a vector by repeatedly applying the monadic generator function to a seed. The generator function yields `Just` the next element and the new seed or `Nothing` if there are no more elements.

constructN :: Int -> (Vector a -> a) -> Vector a #

O(n) Construct a vector with `n` elements by repeatedly applying the generator function to the already constructed part of the vector.

    constructN 3 f = let a = f <> ; b = f <a> ; c = f <a,b> in <a,b,c>

constructrN :: Int -> (Vector a -> a) -> Vector a #

O(n) Construct a vector with `n` elements from right to left by repeatedly applying the generator function to the already constructed part of the vector.

    constructrN 3 f = let a = f <> ; b = f<a> ; c = f <b,a> in <c,b,a>

## Enumeration

enumFromN :: Num a => a -> Int -> Vector a #

O(n) Yield a vector of the given length, containing the values `x`, `x+1` etc. This operation is usually more efficient than `enumFromTo`.

    enumFromN 5 3 = <5,6,7>

enumFromStepN :: Num a => a -> a -> Int -> Vector a #

O(n) Yield a vector of the given length, containing the values `x`, `x+y`, `x+y+y` etc. This operations is usually more efficient than `enumFromThenTo`.

    enumFromStepN 1 2 5 = <1,3,5,7,9>

enumFromTo :: Enum a => a -> a -> Vector a #

O(n) Enumerate values from `x` to `y`.

WARNING: This operation can be very inefficient. If possible, use `enumFromN` instead.

enumFromThenTo :: Enum a => a -> a -> a -> Vector a #

O(n) Enumerate values from `x` to `y` with a specific step `z`.

WARNING: This operation can be very inefficient. If possible, use `enumFromStepN` instead.

## Concatenation

cons :: a -> Vector a -> Vector a #

O(n) Prepend an element.

snoc :: Vector a -> a -> Vector a #

O(n) Append an element.

(++) :: Vector a -> Vector a -> Vector a infixr 5 #

O(m+n) Concatenate two vectors.

concat :: [Vector a] -> Vector a #

O(n) Concatenate all vectors in the list.

## Restricting memory usage

force :: Vector a -> Vector a #

O(n) Yield the argument, but force it not to retain any extra memory, possibly by copying it.

This is especially useful when dealing with slices. For example:

    force (slice 0 2 <huge vector>)

Here, the slice retains a reference to the huge vector. Forcing it creates a copy of just the elements that belong to the slice and allows the huge vector to be garbage collected.

# Modifying vectors

## Permutations

reverse :: Vector a -> Vector a #

O(n) Reverse a vector.

## Safe destructive update

modify :: (forall s. MVector s a -> ST s ()) -> Vector a -> Vector a #

Apply a destructive operation to a vector. The operation may be performed in place if it is safe to do so and will modify a copy of the vector otherwise (see `New` for details).

#### Examples

Expand

    >>> import qualified Data.Vector as V
    >>> import qualified Data.Vector.Mutable as MV
    >>> V.modify (\v -> MV.write v 0 'x') $ V.replicate 4 'a'
    "xaaa"

# Elementwise operations

## Indexing

indexed :: Vector a -> Vector (Int, a) #

O(n) Pair each element in a vector with its index.

## Mapping

map :: (a -> b) -> Vector a -> Vector b #

O(n) Map a function over a vector.

imap :: (Int -> a -> b) -> Vector a -> Vector b #

O(n) Apply a function to every element of a vector and its index.

concatMap :: (a -> Vector b) -> Vector a -> Vector b #

Map a function over a vector and concatenate the results.

## Monadic mapping

mapM :: Monad m => (a -> m b) -> Vector a -> m (Vector b) #

O(n) Apply the monadic action to all elements of the vector, yielding a vector of results.

imapM :: Monad m => (Int -> a -> m b) -> Vector a -> m (Vector b) #

O(n) Apply the monadic action to every element of a vector and its index, yielding a vector of results.

mapM_ :: Monad m => (a -> m b) -> Vector a -> m () #

O(n) Apply the monadic action to all elements of a vector and ignore the results.

imapM_ :: Monad m => (Int -> a -> m b) -> Vector a -> m () #

O(n) Apply the monadic action to every element of a vector and its index, ignoring the results.

forM :: Monad m => Vector a -> (a -> m b) -> m (Vector b) #

O(n) Apply the monadic action to all elements of the vector, yielding a vector of results. Equivalent to `flip `mapM``.

forM_ :: Monad m => Vector a -> (a -> m b) -> m () #

O(n) Apply the monadic action to all elements of a vector and ignore the results. Equivalent to `flip `mapM_``.

## Zipping

zipWith :: (a -> b -> c) -> Vector a -> Vector b -> Vector c #

O(min(m,n)) Zip two vectors with the given function.

zipWith3 :: (a -> b -> c -> d) -> Vector a -> Vector b -> Vector c -> Vector d #

Zip three vectors with the given function.

zipWith4 :: (a -> b -> c -> d -> e) -> Vector a -> Vector b -> Vector c -> Vector d -> Vector e #

zipWith5 :: (a -> b -> c -> d -> e -> f) -> Vector a -> Vector b -> Vector c -> Vector d -> Vector e -> Vector f #

zipWith6 :: (a -> b -> c -> d -> e -> f -> g) -> Vector a -> Vector b -> Vector c -> Vector d -> Vector e -> Vector f -> Vector g #

izipWith :: (Int -> a -> b -> c) -> Vector a -> Vector b -> Vector c #

O(min(m,n)) Zip two vectors with a function that also takes the elements' indices.

izipWith3 :: (Int -> a -> b -> c -> d) -> Vector a -> Vector b -> Vector c -> Vector d #

Zip three vectors and their indices with the given function.

izipWith4 :: (Int -> a -> b -> c -> d -> e) -> Vector a -> Vector b -> Vector c -> Vector d -> Vector e #

izipWith5 :: (Int -> a -> b -> c -> d -> e -> f) -> Vector a -> Vector b -> Vector c -> Vector d -> Vector e -> Vector f #

izipWith6 :: (Int -> a -> b -> c -> d -> e -> f -> g) -> Vector a -> Vector b -> Vector c -> Vector d -> Vector e -> Vector f -> Vector g #

zip :: Vector a -> Vector b -> Vector (a, b) #

O(min(m,n)) Zip two vectors.

zip3 :: Vector a -> Vector b -> Vector c -> Vector (a, b, c) #

Zip together three vectors into a vector of triples.

zip4 :: Vector a -> Vector b -> Vector c -> Vector d -> Vector (a, b, c, d) #

zip5 :: Vector a -> Vector b -> Vector c -> Vector d -> Vector e -> Vector (a, b, c, d, e) #

zip6 :: Vector a -> Vector b -> Vector c -> Vector d -> Vector e -> Vector f -> Vector (a, b, c, d, e, f) #

## Monadic zipping

zipWithM :: Monad m => (a -> b -> m c) -> Vector a -> Vector b -> m (Vector c) #

O(min(m,n)) Zip the two vectors with the monadic action and yield a vector of results.

izipWithM :: Monad m => (Int -> a -> b -> m c) -> Vector a -> Vector b -> m (Vector c) #

O(min(m,n)) Zip the two vectors with a monadic action that also takes the element index and yield a vector of results.

zipWithM_ :: Monad m => (a -> b -> m c) -> Vector a -> Vector b -> m () #

O(min(m,n)) Zip the two vectors with the monadic action and ignore the results.

izipWithM_ :: Monad m => (Int -> a -> b -> m c) -> Vector a -> Vector b -> m () #

O(min(m,n)) Zip the two vectors with a monadic action that also takes the element index and ignore the results.

## Unzipping

unzip :: Vector (a, b) -> (Vector a, Vector b) #

O(min(m,n)) Unzip a vector of pairs.

unzip3 :: Vector (a, b, c) -> (Vector a, Vector b, Vector c) #

unzip4 :: Vector (a, b, c, d) -> (Vector a, Vector b, Vector c, Vector d) #

unzip5 :: Vector (a, b, c, d, e) -> (Vector a, Vector b, Vector c, Vector d, Vector e) #

unzip6 :: Vector (a, b, c, d, e, f) -> (Vector a, Vector b, Vector c, Vector d, Vector e, Vector f) #

# Working with predicates

## Filtering

filter :: (a -> Bool) -> Vector a -> Vector a #

O(n) Drop all elements that do not satisfy the predicate.

ifilter :: (Int -> a -> Bool) -> Vector a -> Vector a #

O(n) Drop all elements that do not satisfy the predicate which is applied to the values and their indices.

uniq :: Eq a => Vector a -> Vector a #

O(n) Drop repeated adjacent elements. The first element in each group is returned.

#### Examples

Expand

    >>> import qualified Data.Vector as V
    >>> V.uniq $ V.fromList [1,3,3,200,3]
    [1,3,200,3]
    >>> import Data.Semigroup
    >>> V.uniq $ V.fromList [ Arg 1 'a', Arg 1 'b', Arg 1 'c']
    [Arg 1 'a']

mapMaybe :: (a -> Maybe b) -> Vector a -> Vector b #

O(n) Map the values and collect the `Just` results.

imapMaybe :: (Int -> a -> Maybe b) -> Vector a -> Vector b #

O(n) Map the indices/values and collect the `Just` results.

filterM :: Monad m => (a -> m Bool) -> Vector a -> m (Vector a) #

O(n) Drop all elements that do not satisfy the monadic predicate.

takeWhile :: (a -> Bool) -> Vector a -> Vector a #

O(n) Yield the longest prefix of elements satisfying the predicate. The current implementation is not copy-free, unless the result vector is fused away.

dropWhile :: (a -> Bool) -> Vector a -> Vector a #

O(n) Drop the longest prefix of elements that satisfy the predicate without copying.

## Partitioning

partition :: (a -> Bool) -> Vector a -> (Vector a, Vector a) #

O(n) Split the vector in two parts, the first one containing those elements that satisfy the predicate and the second one those that don't. The relative order of the elements is preserved at the cost of a sometimes reduced performance compared to `unstablePartition`.

unstablePartition :: (a -> Bool) -> Vector a -> (Vector a, Vector a) #

O(n) Split the vector in two parts, the first one containing those elements that satisfy the predicate and the second one those that don't. The order of the elements is not preserved, but the operation is often faster than `partition`.

span :: (a -> Bool) -> Vector a -> (Vector a, Vector a) #

O(n) Split the vector into the longest prefix of elements that satisfy the predicate and the rest without copying.

break :: (a -> Bool) -> Vector a -> (Vector a, Vector a) #

O(n) Split the vector into the longest prefix of elements that do not satisfy the predicate and the rest without copying.

## Searching

elem :: Eq a => a -> Vector a -> Bool infix 4 #

O(n) Check if the vector contains an element.

notElem :: Eq a => a -> Vector a -> Bool infix 4 #

O(n) Check if the vector does not contain an element (inverse of `elem`).

find :: (a -> Bool) -> Vector a -> Maybe a #

O(n) Yield `Just` the first element matching the predicate or `Nothing` if no such element exists.

findIndex :: (a -> Bool) -> Vector a -> Maybe Int #

O(n) Yield `Just` the index of the first element matching the predicate or `Nothing` if no such element exists.

findIndices :: (a -> Bool) -> Vector a -> Vector Int #

O(n) Yield the indices of elements satisfying the predicate in ascending order.

elemIndex :: Eq a => a -> Vector a -> Maybe Int #

O(n) Yield `Just` the index of the first occurrence of the given element or `Nothing` if the vector does not contain the element. This is a specialised version of `findIndex`.

elemIndices :: Eq a => a -> Vector a -> Vector Int #

O(n) Yield the indices of all occurrences of the given element in ascending order. This is a specialised version of `findIndices`.

# Folding

foldl :: (a -> b -> a) -> a -> Vector b -> a #

O(n) Left fold.

foldl' :: (a -> b -> a) -> a -> Vector b -> a #

O(n) Left fold with strict accumulator.

foldr :: (a -> b -> b) -> b -> Vector a -> b #

O(n) Right fold.

foldr' :: (a -> b -> b) -> b -> Vector a -> b #

O(n) Right fold with a strict accumulator.

ifoldl :: (a -> Int -> b -> a) -> a -> Vector b -> a #

O(n) Left fold using a function applied to each element and its index.

ifoldl' :: (a -> Int -> b -> a) -> a -> Vector b -> a #

O(n) Left fold with strict accumulator using a function applied to each element and its index.

ifoldr :: (Int -> a -> b -> b) -> b -> Vector a -> b #

O(n) Right fold using a function applied to each element and its index.

ifoldr' :: (Int -> a -> b -> b) -> b -> Vector a -> b #

O(n) Right fold with strict accumulator using a function applied to each element and its index.

## Specialised folds

all :: (a -> Bool) -> Vector a -> Bool #

O(n) Check if all elements satisfy the predicate.

#### Examples

Expand

    >>> import qualified Data.Vector as V
    >>> V.all even $ V.fromList [2, 4, 12]
    True
    >>> V.all even $ V.fromList [2, 4, 13]
    False
    >>> V.all even (V.empty :: V.Vector Int)
    True

any :: (a -> Bool) -> Vector a -> Bool #

O(n) Check if any element satisfies the predicate.

#### Examples

Expand

    >>> import qualified Data.Vector as V
    >>> V.any even $ V.fromList [1, 3, 7]
    False
    >>> V.any even $ V.fromList [3, 2, 13]
    True
    >>> V.any even (V.empty :: V.Vector Int)
    False

and :: Vector Bool -> Bool #

O(n) Check if all elements are `True`.

#### Examples

Expand

    >>> import qualified Data.Vector as V
    >>> V.and $ V.fromList [True, False]
    False
    >>> V.and V.empty
    True

or :: Vector Bool -> Bool #

O(n) Check if any element is `True`.

#### Examples

Expand

    >>> import qualified Data.Vector as V
    >>> V.or $ V.fromList [True, False]
    True
    >>> V.or V.empty
    False

sum :: Num a => Vector a -> a #

O(n) Compute the sum of the elements.

#### Examples

Expand

    >>> import qualified Data.Vector as V
    >>> V.sum $ V.fromList [300,20,1]
    321
    >>> V.sum (V.empty :: V.Vector Int)
    0

product :: Num a => Vector a -> a #

O(n) Compute the product of the elements.

#### Examples

Expand

    >>> import qualified Data.Vector as V
    >>> V.product $ V.fromList [1,2,3,4]
    24
    >>> V.product (V.empty :: V.Vector Int)
    1

## Monadic folds

foldM :: Monad m => (a -> b -> m a) -> a -> Vector b -> m a #

O(n) Monadic fold.

ifoldM :: Monad m => (a -> Int -> b -> m a) -> a -> Vector b -> m a #

O(n) Monadic fold using a function applied to each element and its index.

foldM' :: Monad m => (a -> b -> m a) -> a -> Vector b -> m a #

O(n) Monadic fold with strict accumulator.

ifoldM' :: Monad m => (a -> Int -> b -> m a) -> a -> Vector b -> m a #

O(n) Monadic fold with strict accumulator using a function applied to each element and its index.

foldM_ :: Monad m => (a -> b -> m a) -> a -> Vector b -> m () #

O(n) Monadic fold that discards the result.

ifoldM_ :: Monad m => (a -> Int -> b -> m a) -> a -> Vector b -> m () #

O(n) Monadic fold that discards the result using a function applied to each element and its index.

foldM'_ :: Monad m => (a -> b -> m a) -> a -> Vector b -> m () #

O(n) Monadic fold with strict accumulator that discards the result.

ifoldM'_ :: Monad m => (a -> Int -> b -> m a) -> a -> Vector b -> m () #

O(n) Monadic fold with strict accumulator that discards the result using a function applied to each element and its index.

## Monadic sequencing

sequence :: Monad m => Vector (m a) -> m (Vector a) #

Evaluate each action and collect the results.

sequence_ :: Monad m => Vector (m a) -> m () #

Evaluate each action and discard the results.

# Prefix sums (scans)

prescanl :: (a -> b -> a) -> a -> Vector b -> Vector a #

O(n) Left-to-right prescan.

    prescanl f z = init . scanl f z

#### Examples

Expand

    >>> import qualified Data.Vector as V
    >>> V.prescanl (+) 0 (V.fromList [1,2,3,4])
    [0,1,3,6]

prescanl' :: (a -> b -> a) -> a -> Vector b -> Vector a #

O(n) Left-to-right prescan with strict accumulator.

postscanl :: (a -> b -> a) -> a -> Vector b -> Vector a #

O(n) Left-to-right postscan.

    postscanl f z = tail . scanl f z

#### Examples

Expand

    >>> import qualified Data.Vector as V
    >>> V.postscanl (+) 0 (V.fromList [1,2,3,4])
    [1,3,6,10]

postscanl' :: (a -> b -> a) -> a -> Vector b -> Vector a #

O(n) Left-to-right postscan with strict accumulator.

scanl :: (a -> b -> a) -> a -> Vector b -> Vector a #

O(n) Left-to-right scan.

    scanl f z <x1,...,xn> = <y1,...,y(n+1)>
      where y1 = z
            yi = f y(i-1) x(i-1)

#### Examples

Expand

    >>> import qualified Data.Vector as V
    >>> V.scanl (+) 0 (V.fromList [1,2,3,4])
    [0,1,3,6,10]

scanl' :: (a -> b -> a) -> a -> Vector b -> Vector a #

O(n) Left-to-right scan with strict accumulator.

iscanl :: (Int -> a -> b -> a) -> a -> Vector b -> Vector a #

O(n) Left-to-right scan over a vector with its index.

Since: vector-0.12.0.0

iscanl' :: (Int -> a -> b -> a) -> a -> Vector b -> Vector a #

O(n) Left-to-right scan over a vector (strictly) with its index.

Since: vector-0.12.0.0

prescanr :: (a -> b -> b) -> b -> Vector a -> Vector b #

O(n) Right-to-left prescan.

    prescanr f z = reverse . prescanl (flip f) z . reverse

prescanr' :: (a -> b -> b) -> b -> Vector a -> Vector b #

O(n) Right-to-left prescan with strict accumulator.

postscanr :: (a -> b -> b) -> b -> Vector a -> Vector b #

O(n) Right-to-left postscan.

postscanr' :: (a -> b -> b) -> b -> Vector a -> Vector b #

O(n) Right-to-left postscan with strict accumulator.

scanr :: (a -> b -> b) -> b -> Vector a -> Vector b #

O(n) Right-to-left scan.

scanr' :: (a -> b -> b) -> b -> Vector a -> Vector b #

O(n) Right-to-left scan with strict accumulator.

iscanr :: (Int -> a -> b -> b) -> b -> Vector a -> Vector b #

O(n) Right-to-left scan over a vector with its index.

Since: vector-0.12.0.0

iscanr' :: (Int -> a -> b -> b) -> b -> Vector a -> Vector b #

O(n) Right-to-left scan over a vector (strictly) with its index.

Since: vector-0.12.0.0

# Conversions

## Lists

toList :: Vector a -> [a] #

O(n) Convert a vector to a list.

fromList :: [a] -> Vector a #

O(n) Convert a list to a vector.

fromListN :: Int -> [a] -> Vector a #

O(n) Convert the first `n` elements of a list to a vector. It's expected that the supplied list will be exactly `n` elements long. As an optimization, this function allocates a buffer for `n` elements, which could be used for DoS-attacks by exhausting the memory if an attacker controls that parameter.

    fromListN n xs = fromList (take n xs)

## Different vector types

convert :: (Vector v a, Vector w a) => v a -> w a #

O(n) Convert between different vector types.

## Mutable vectors

freeze :: PrimMonad m => MVector (PrimState m) a -> m (Vector a) #

O(n) Yield an immutable copy of the mutable vector.

thaw :: PrimMonad m => Vector a -> m (MVector (PrimState m) a) #

O(n) Yield a mutable copy of an immutable vector.

copy :: PrimMonad m => MVector (PrimState m) a -> Vector a -> m () #

O(n) Copy an immutable vector into a mutable one. The two vectors must have the same length.