| Safe Haskell | None |
|---|---|
| Language | Haskell2010 |
CLaSH.Sized.Vector
Contents
- data Vec :: Nat -> * -> * where
- (<:) :: Vec n a -> a -> Vec (n + 1) a
- singleton :: a -> Vec 1 a
- head :: Vec (n + 1) a -> a
- tail :: Vec (n + 1) a -> Vec n a
- last :: Vec (n + 1) a -> a
- init :: Vec (n + 1) a -> Vec n a
- take :: SNat m -> Vec (m + n) a -> Vec m a
- takeI :: KnownNat m => Vec (m + n) a -> Vec m a
- drop :: SNat m -> Vec (m + n) a -> Vec n a
- dropI :: KnownNat m => Vec (m + n) a -> Vec n a
- exact :: SNat m -> Vec (m + (n + 1)) a -> a
- select :: (CmpNat (i + s) (s * n) ~ GT) => SNat f -> SNat s -> SNat n -> Vec (f + i) a -> Vec n a
- selectI :: (CmpNat (i + s) (s * n) ~ GT, KnownNat n) => SNat f -> SNat s -> Vec (f + i) a -> Vec n a
- (++) :: Vec n a -> Vec m a -> Vec (n + m) a
- (+>>) :: KnownNat n => a -> Vec n a -> Vec n a
- (<<+) :: KnownNat n => Vec n a -> a -> Vec n a
- concat :: Vec n (Vec m a) -> Vec (n * m) a
- zip :: Vec n a -> Vec n b -> Vec n (a, b)
- unzip :: Vec n (a, b) -> (Vec n a, Vec n b)
- shiftInAt0 :: KnownNat n => Vec n a -> Vec m a -> (Vec n a, Vec m a)
- shiftInAtN :: KnownNat m => Vec n a -> Vec m a -> (Vec n a, Vec m a)
- shiftOutFrom0 :: (Default a, KnownNat m) => SNat m -> Vec (m + n) a -> (Vec (m + n) a, Vec m a)
- shiftOutFromN :: (Default a, KnownNat (m + n)) => SNat m -> Vec (m + n) a -> (Vec (m + n) a, Vec m a)
- splitAt :: SNat m -> Vec (m + n) a -> (Vec m a, Vec n a)
- splitAtI :: KnownNat m => Vec (m + n) a -> (Vec m a, Vec n a)
- unconcat :: KnownNat n => SNat m -> Vec (n * m) a -> Vec n (Vec m a)
- unconcatI :: (KnownNat n, KnownNat m) => Vec (n * m) a -> Vec n (Vec m a)
- merge :: Vec n a -> Vec n a -> Vec (n + n) a
- map :: (a -> b) -> Vec n a -> Vec n b
- zipWith :: (a -> b -> c) -> Vec n a -> Vec n b -> Vec n c
- foldr :: (a -> b -> b) -> b -> Vec n a -> b
- foldl :: (b -> a -> b) -> b -> Vec n a -> b
- foldr1 :: (a -> a -> a) -> Vec (n + 1) a -> a
- foldl1 :: (a -> a -> a) -> Vec (n + 1) a -> a
- fold :: (a -> a -> a) -> Vec (n + 1) a -> a
- scanl :: (b -> a -> b) -> b -> Vec n a -> Vec (n + 1) b
- scanr :: (a -> b -> b) -> b -> Vec n a -> Vec (n + 1) b
- sscanl :: (b -> a -> b) -> b -> Vec n a -> Vec n b
- sscanr :: (a -> b -> b) -> b -> Vec n a -> Vec n b
- mapAccumL :: (acc -> x -> (acc, y)) -> acc -> Vec n x -> (acc, Vec n y)
- mapAccumR :: (acc -> x -> (acc, y)) -> acc -> Vec n x -> (acc, Vec n y)
- (!!) :: (KnownNat n, Integral i) => Vec n a -> i -> a
- replace :: (KnownNat n, Integral i) => Vec n a -> i -> a -> Vec n a
- maxIndex :: KnownNat n => Vec n a -> Integer
- length :: KnownNat n => Vec n a -> Integer
- replicate :: SNat n -> a -> Vec n a
- repeat :: KnownNat n => a -> Vec n a
- iterate :: SNat n -> (a -> a) -> a -> Vec n a
- iterateI :: KnownNat n => (a -> a) -> a -> Vec n a
- generate :: SNat n -> (a -> a) -> a -> Vec n a
- generateI :: KnownNat n => (a -> a) -> a -> Vec n a
- reverse :: Vec n a -> Vec n a
- toList :: Vec n a -> [a]
- v :: Lift a => [a] -> ExpQ
- lazyV :: KnownNat n => Vec n a -> Vec n a
- asNatProxy :: Vec n a -> Proxy n
- concatBitVector# :: KnownNat m => Vec n (BitVector m) -> BitVector (n * m)
- unconcatBitVector# :: (KnownNat n, KnownNat m) => BitVector (n * m) -> Vec n (BitVector m)
Vector constructors
data Vec :: Nat -> * -> * where Source
Fixed size vectors
- Lists with their length encoded in their type
Vector elements have an ASCENDING subscript starting from 0 and ending atmaxIndex(==length- 1).
>>>(3:>4:>5:>Nil)<3,4,5>>>>:t (3:>4:>5:>Nil)(3:>4:>5:>Nil) :: Num a => Vec 3 a
Instances
| Functor (Vec n) | |
| KnownNat n => Applicative (Vec n) | NB: Not synthesisable |
| Foldable (Vec n) | |
| Traversable (Vec n) | NB: Not synthesisable |
| Eq a => Eq (Vec n a) | |
| Show a => Show (Vec n a) | |
| (Default a, KnownNat n) => Default (Vec n a) | |
| (KnownNat n, KnownNat (BitSize a), BitPack a) => BitPack (Vec n a) | |
| KnownNat n => Bundle (Vec n a) | |
| type Unbundled t (Vec n a) = Vec n (CSignal t a) | |
| type BitSize (Vec n a) = * n (BitSize a) |
(<:) :: Vec n a -> a -> Vec (n + 1) a infixl 5 Source
Add an element to the tail of a vector.
>>>(3:>4:>5:>Nil) <: 1<3,4,5,1>>>>:t (3:>4:>5:>Nil) <: 1(3:>4:>5:>Nil) <: 1 :: Num a => Vec 4 a
Standard Vector functions
Extracting sub-Vectors
head :: Vec (n + 1) a -> a Source
Extract the first element of a vector
>>>head (1:>2:>3:>Nil)1>>>head Nil<interactive> Couldn't match type ‘1’ with ‘0’ Expected type: Vec (0 + 1) a Actual type: Vec 0 a In the first argument of ‘vhead’, namely ‘Nil’ In the expression: vhead Nil
tail :: Vec (n + 1) a -> Vec n a Source
Extract the elements after the head of a vector
>>>tail (1:>2:>3:>Nil)<2,3>>>>tail Nil<interactive> Couldn't match type ‘1’ with ‘0’ Expected type: Vec (0 + 1) a Actual type: Vec 0 a In the first argument of ‘vtail’, namely ‘Nil’ In the expression: vtail Nil
last :: Vec (n + 1) a -> a Source
Extract the last element of a vector
>>>last (1:>2:>3:>Nil)3>>>last Nil<interactive> Couldn't match type ‘1’ with ‘0’ Expected type: Vec (0 + 1) a Actual type: Vec 0 a In the first argument of ‘vlast’, namely ‘Nil’ In the expression: vlast Nil
init :: Vec (n + 1) a -> Vec n a Source
Extract all the elements of a vector except the last element
>>>init (1:>2:>3:>Nil)<1,2>>>>init Nil<interactive> Couldn't match type ‘1’ with ‘0’ Expected type: Vec (0 + 1) a Actual type: Vec 0 a In the first argument of ‘vinit’, namely ‘Nil’ In the expression: vinit Nil
take :: SNat m -> Vec (m + n) a -> Vec m a Source
take n, applied to a vector xs, returns the n-length prefix of xs
>>>take (snat :: SNat 3) (1:>2:>3:>4:>5:>Nil)<1,2,3>>>>take d3 (1:>2:>3:>4:>5:>Nil)<1,2,3>>>>take d0 (1:>2:>Nil)<>>>>take d4 (1:>2:>Nil)<interactive> Couldn't match type ‘4 + n0’ with ‘2’ The type variable ‘n0’ is ambiguous Expected type: Vec (4 + n0) a Actual type: Vec (1 + 1) a In the second argument of ‘vtake’, namely ‘(1 :> 2 :> Nil)’ In the expression: vtake d4 (1 :> 2 :> Nil) In an equation for ‘it’: it = vtake d4 (1 :> 2 :> Nil)
takeI :: KnownNat m => Vec (m + n) a -> Vec m a Source
takeI xs, returns the prefix of xs as demanded by the context
>>>takeI (1:>2:>3:>4:>5:>Nil) :: Vec 2 Int<1,2>
drop :: SNat m -> Vec (m + n) a -> Vec n a Source
drop n xs returns the suffix of xs after the first n elements
>>>drop (snat :: SNat 3) (1:>2:>3:>4:>5:>Nil)<4,5>>>>drop d3 (1:>2:>3:>4:>5:>Nil)<4,5>>>>drop d0 (1:>2:>Nil)<1,2>>>>drop d4 (1:>2:>Nil)<interactive> Couldn't match expected type ‘2’ with actual type ‘4 + n0’ The type variable ‘n0’ is ambiguous In the first argument of ‘print’, namely ‘it’ In a stmt of an interactive GHCi command: print it
dropI :: KnownNat m => Vec (m + n) a -> Vec n a Source
dropI xs, returns the suffix of xs as demanded by the context
>>>dropI (1:>2:>3:>4:>5:>Nil) :: Vec 2 Int<4,5>
select :: (CmpNat (i + s) (s * n) ~ GT) => SNat f -> SNat s -> SNat n -> Vec (f + i) a -> Vec n a Source
select f s n xs selects n elements with stepsize s and
offset f from xs
>>>select (snat :: SNat 1) (snat :: SNat 2) (snat :: SNat 3) (1:>2:>3:>4:>5:>6:>7:>8:>Nil)<2,4,6>>>>select d1 d2 d3 (1:>2:>3:>4:>5:>6:>7:>8:>Nil)<2,4,6>
selectI :: (CmpNat (i + s) (s * n) ~ GT, KnownNat n) => SNat f -> SNat s -> Vec (f + i) a -> Vec n a Source
selectI f s xs selects as many elements as demanded by the context
with stepsize s and offset f from xs
>>>selectI d1 d2 (1:>2:>3:>4:>5:>6:>7:>8:>Nil) :: Vec 2 Int<2,4>
Combining Vectors
(++) :: Vec n a -> Vec m a -> Vec (n + m) a infixr 5 Source
Append two vectors
>>>(1:>2:>3:>Nil) ++ (7:>8:>Nil)<1,2,3,7,8>
(+>>) :: KnownNat n => a -> Vec n a -> Vec n a infixr 4 Source
Add an element to the head of a vector, and extract all but the last element.
>>>1 +>> (3:>4:>5:>Nil)<1,3,4>>>>1 +>> Nil<>
(<<+) :: KnownNat n => Vec n a -> a -> Vec n a infixl 4 Source
Add an element to the tail of a vector, and extract all but the first element.
>>>(3:>4:>5:>Nil) <<+ 1<4,5,1>>>>Nil <<+ 1<>
concat :: Vec n (Vec m a) -> Vec (n * m) a Source
Concatenate a vector of vectors
>>>vconcat ((1:>2:>3:>Nil) :> (4:>5:>6:>Nil) :> (7:>8:>9:>Nil) :> (10:>11:>12:>Nil) :> Nil)<1,2,3,4,5,6,7,8,9,10,11,12>
zip :: Vec n a -> Vec n b -> Vec n (a, b) Source
zip takes two vectors and returns a vector of corresponding pairs.
>>>zip (1:>2:>3:>4:>Nil) (4:>3:>2:>1:>Nil)<(1,4),(2,3),(3,2),(4,1)>
unzip :: Vec n (a, b) -> (Vec n a, Vec n b) Source
unzip transforms a vector of pairs into a vector of first components
and a vector of second components.
>>>unzip ((1,4):>(2,3):>(3,2):>(4,1):>Nil)(<1,2,3,4>,<4,3,2,1>)
Arguments
| :: KnownNat n | |
| => Vec n a | The old vector |
| -> Vec m a | The elements to shift in at the head |
| -> (Vec n a, Vec m a) | (The new vector, shifted out elements) |
Shift in elements to the head of a vector, bumping out elements at the tail. The result is a tuple containing:
- The new vector
- The shifted out elements
>>>shiftInAt0 (1 :> 2 :> 3 :> 4 :> Nil) ((-1) :> 0 :> Nil)(<-1,0,1,2,>,<3,4>)>>>shiftInAt0 (1 :> Nil) ((-1) :> 0 :> Nil)(<-1>,<0,1>)
Arguments
| :: KnownNat m | |
| => Vec n a | The old vector |
| -> Vec m a | The elements to shift in at the tail |
| -> (Vec n a, Vec m a) | (The new vector, shifted out elements) |
Shift in element to the tail of a vector, bumping out elements at the head. The result is a tuple containing:
- The new vector
- The shifted out elements
>>>shiftInAtN (1 :> 2 :> 3 :> 4 :> Nil) (5 :> 6 :> Nil)(<3,4,5,6>,<1,2>)>>>shiftInAtN (1 :> Nil) (2 :> 3 :> Nil)(<3>,<1,2>)
Arguments
| :: (Default a, KnownNat m) | |
| => SNat m |
|
| -> Vec (m + n) a | The old vector |
| -> (Vec (m + n) a, Vec m a) | (The new vector, shifted out elements) |
Shift m elements out from the head of a vector, filling up the tail with
Default values. The result is a tuple containing:
- The new vector
- The shifted out values
>>>shiftOutFrom0 d2 ((1 :> 2 :> 3 :> 4 :> 5 :> Nil) :: Vec 5 Integer)(<3,4,5,0,0>,<1,2>)
Arguments
| :: (Default a, KnownNat (m + n)) | |
| => SNat m |
|
| -> Vec (m + n) a | The old vector |
| -> (Vec (m + n) a, Vec m a) | (The new vector, shifted out elements) |
Shift m elements out from the tail of a vector, filling up the head with
Default values. The result is a tuple containing:
- The new vector
- The shifted out values
>>>shiftOutFromN d2 ((1 :> 2 :> 3 :> 4 :> 5 :> Nil) :: Vec 5 Integer)(<0,0,1,2,3>,<4,5>)
Splitting Vectors
splitAt :: SNat m -> Vec (m + n) a -> (Vec m a, Vec n a) Source
Split a vector into two vectors at the given point
>>>splitAt (snat :: SNat 3) (1:>2:>3:>7:>8:>Nil)(<1,2,3>, <7,8>)>>>splitAt d3 (1:>2:>3:>7:>8:>Nil)(<1,2,3>, <7,8>)
splitAtI :: KnownNat m => Vec (m + n) a -> (Vec m a, Vec n a) Source
Split a vector into two vectors where the length of the two is determined by the context
>>>splitAtI (1:>2:>3:>7:>8:>Nil) :: (Vec 2 Int, Vec 3 Int)(<1,2>,<3,7,8>)
unconcat :: KnownNat n => SNat m -> Vec (n * m) a -> Vec n (Vec m a) Source
Split a vector of (n * m) elements into a vector of vectors with length m, where m is given
>>>vunconcat d4 (1:>2:>3:>4:>5:>6:>7:>8:>9:>10:>11:>12:>Nil)<<1,2,3,4>,<5,6,7,8>,<9,10,11,12>>
unconcatI :: (KnownNat n, KnownNat m) => Vec (n * m) a -> Vec n (Vec m a) Source
Split a vector of (n * m) elements into a vector of vectors with length m, where m is determined by the context
>>>vunconcatI (1:>2:>3:>4:>5:>6:>7:>8:>9:>10:>11:>12:>Nil) :: Vec 2 (Vec 6 Int)<<1,2,3,4,5,6>,<7,8,9,10,11,12>>
merge :: Vec n a -> Vec n a -> Vec (n + n) a Source
Merge two vectors, alternating their elements, i.e.,
>>>merge (1 :> 2 :> 3 :> 4 :> Nil) (5 :> 6 :> 7 :> 8 :> Nil)<1,5,2,6,3,7,4,8>
Applying functions to Vector elements
map :: (a -> b) -> Vec n a -> Vec n b Source
map f xs is the vector obtained by applying f to each element
of xs, i.e.,
map f (x1 :> x2 :> ... :> xn :> Nil) == (f x1 :> f x2 :> ... :> f xn :> Nil)
zipWith :: (a -> b -> c) -> Vec n a -> Vec n b -> Vec n c Source
zipWith generalises zip by zipping with the function given
as the first argument, instead of a tupling function.
For example, is applied to two vectors to produce the
vector of corresponding sums.zipWith (+)
zipWith f (x1 :> x2 :> ... xn :> Nil) (y1 :> y2 :> ... :> yn :> Nil) == (f x1 y1 :> f x2 y2 :> ... :> f xn yn :> Nil)
NB: zipWith is strict in its second argument, and lazy in its
third. This matters when zipWith is used in a recursive setting. See
lazyV for more information.
foldr :: (a -> b -> b) -> b -> Vec n a -> b Source
vfoldr, applied to a binary operator, a starting value (typically
the right-identity of the operator), and a vector, reduces the vector
using the binary operator, from right to left:
foldr f z (x1 :> ... :> xn1 :> xn :> Nil) == x1 `f` (... (xn1 `f` (xn `f` z))...) foldr r z Nil == z
>>>foldr (/) 1 (5 :> 4 :> 3 :> 2 :> Nil)1.875
NB: " produces a linear structure, which has a depth, or
delay, of O(foldr f z xs"). Use length xsfold if your binary operator f is
associative, as " produces a structure with a depth of
O(log_2(fold f xs")).length xs
foldl :: (b -> a -> b) -> b -> Vec n a -> b Source
foldl, applied to a binary operator, a starting value (typically
the left-identity of the operator), and a vector, reduces the vector
using the binary operator, from left to right:
foldl f z (x1 :> x2 :> ... :> xn :> Nil) == (...((z `f` x1) `f` x2) `f`...) `f` xn foldl f z Nil == z
>>>foldl (/) 1 (5 :> 4 :> 3 :> 2 :> Nil)8.333333333333333e-3
NB: " produces a linear structure, which has a depth, or
delay, of O(foldl f z xs"). Use length xsfold if your binary operator f is
associative, as " produces a structure with a depth of
O(log_2(fold f xs")).length xs
foldr1 :: (a -> a -> a) -> Vec (n + 1) a -> a Source
foldr1 is a variant of foldr that has no starting value argument,
and thus must be applied to non-empty vectors.
foldr1 f (x1 :> ... :> xn2 :> xn1 :> xn :> Nil) == x1 `f` (... (xn2 `f` (xn1 `f` xn))...) foldr1 f (x1 :> Nil) == x1 foldr1 f Nil == TYPE ERROR
>>>foldr1 (/) (5 :> 4 :> 3 :> 2 :> 1 :> Nil)1.875
NB: " produces a linear structure, which has a depth,
or delay, of O(foldr1 f z xs"). Use length xsfold if your binary operator f is
associative, as " produces a structure with a depth of
O(log_2(fold f xs")).length xs
foldl1 :: (a -> a -> a) -> Vec (n + 1) a -> a Source
foldl1 is a variant of foldl that has no starting value argument,
and thus must be applied to non-empty vectors.
foldl1 f (x1 :> x2 :> x3 :> ... :> xn :> Nil) == (...((x1 `f` x2) `f` x3) `f`...) `f` xn foldl1 f (x1 :> Nil) == x1 foldl1 f Nil == TYPE ERROR
>>>foldl1 (/) (1 :> 5 :> 4 :> 3 :> 2 :> Nil)8.333333333333333e-3
NB: " produces a linear structure, which has a depth,
or delay, of O(foldl1 f z xs"). Use length xsfold if your binary operator f is
associative, as " produces a structure with a depth of
O(log_2(fold f xs")).length xs
fold :: (a -> a -> a) -> Vec (n + 1) a -> a Source
fold is a variant of foldr1 and foldl1, but instead of reducing from
right to left, or left to right, it reduces a vector using a tree-like
structure. The depth, or delay, of the structure produced by
"", is hence fold f xsO(log_2(, and not
length xs))O(.length xs)
NB: The binary operator "f in " must be associative.fold f xs
fold f (x1 :> x2 :> ... :> xn1 :> xn :> Nil) == ((x1 `f` x2) `f` ...) `f` (... `f` (xn1 `f` xn)) fold f (x1 :> Nil) == x1 fold f Nil == TYPE ERROR
>>>fold (+) (5 :> 4 :> 3 :> 2 :> 1 :> Nil)15
mapAccumL :: (acc -> x -> (acc, y)) -> acc -> Vec n x -> (acc, Vec n y) Source
The mapAccumL function behaves like a combination of map and foldl;
it applies a function to each element of a vector, passing an accumulating
parameter from left to right, and returning a final value of this accumulator
together with the new vector.
>>>mapAccumL (\acc x -> (acc + x,acc + 1)) 0 (1 :> 2 :> 3 :> 4 :> Nil)(10,<1,2,4,7>)
mapAccumR :: (acc -> x -> (acc, y)) -> acc -> Vec n x -> (acc, Vec n y) Source
The mapAccumR function behaves like a combination of map and foldr;
it applies a function to each element of a vector, passing an accumulating
parameter from right to left, and returning a final value of this accumulator
together with the new vector.
>>>mapAccumR (\acc x -> (acc + x,acc + 1)) 0 (1 :> 2 :> 3 :> 4 :> Nil)(10,<10,8,5,1>)
Indexing Vectors
(!!) :: (KnownNat n, Integral i) => Vec n a -> i -> a Source
Vector index (subscript) operator.
NB: vector elements have an ASCENDING subscript starting from 0 and
ending at maxIndex.
>>>(1:>2:>3:>4:>5:>Nil) !! 45>>>(1:>2:>3:>4:>5:>Nil) !! maxIndex5>>>(1:>2:>3:>4:>5:>Nil) !! 12>>>(1:>2:>3:>4:>5:>Nil) !! 14*** Exception: (!!): Index 14 is out of bounds [0..4]
replace :: (KnownNat n, Integral i) => Vec n a -> i -> a -> Vec n a Source
Replace an element of a vector at the given index (subscript).
NB: vector elements have an ASCENDING subscript starting from 0 and
ending at maxIndex.
>>>replace (1:>2:>3:>4:>5:>Nil) 3 7<1,2,3,7,5>>>>replace (1:>2:>3:>4:>5:>Nil) 0 7<7,2,3,4,5>>>>replace (1:>2:>3:>4:>5:>Nil) 9 7<*** Exception: replace: Index 9 is out of bounds [0..4]
maxIndex :: KnownNat n => Vec n a -> Integer Source
Index (subscript) of the last element in a Vector
>>>maxIndex (6 :> 7 :> 8 :> Nil)2
length :: KnownNat n => Vec n a -> Integer Source
Length of a Vector as an Integer
>>>length (6 :> 7 :> 8 :> Nil)3
Generating Vectors
replicate :: SNat n -> a -> Vec n a Source
replicate n a returns a vector that has n copies of a
>>>replicate (snat :: SNat 3) 6<6,6,6>>>>replicate d3 6<6,6,6>
repeat :: KnownNat n => a -> Vec n a Source
repeat a creates a vector with as many copies of a as demanded by the
context
>>>repeat 6 :: Vec 5 Int<6,6,6,6,6>
iterate :: SNat n -> (a -> a) -> a -> Vec n a Source
iterate n f x returns a vector starting with x followed by n
repeated applications of f to x
iterate (snat :: SNat 4) f x == (x :> f x :> f (f x) :> f (f (f x)) :> Nil) iterate d4 f x == (x :> f x :> f (f x) :> f (f (f x)) :> Nil)
>>>iterate d4 (+1) 1<1,2,3,4>
iterateI :: KnownNat n => (a -> a) -> a -> Vec n a Source
iterate f x returns a vector starting with x followed by n
repeated applications of f to x, where n is determined by the context
iterateI f x :: Vec 3 a == (x :> f x :> f (f x) :> Nil)
>>>iterateI (+1) 1 :: Vec 3 Int<1,2,3>
generate :: SNat n -> (a -> a) -> a -> Vec n a Source
generate n f x returns a vector with n repeated applications of f
to x
generate (snat :: SNat 4) f x == (f x :> f (f x) :> f (f (f x)) :> f (f (f (f x))) :> Nil) generate d4 f x == (f x :> f (f x) :> f (f (f x)) :> f (f (f (f x))) :> Nil)
>>>generate d4 (+1) 1<2,3,4,5>
generateI :: KnownNat n => (a -> a) -> a -> Vec n a Source
generate f x returns a vector with n repeated applications of f
to x, where n is determined by the context
generateI f x :: Vec 3 a == (f x :> f (f x) :> f (f (f x)) :> Nil)
>>>generateI (+1) 1 :: Vec 3 Int<2,3,4>
Misc
reverse :: Vec n a -> Vec n a Source
Returns the elements in a vector in reverse order
>>>reverse (1:>2:>3:>4:>Nil)<4,3,2,1>
toList :: Vec n a -> [a] Source
Convert a vector to a list
>>>toList (1:>2:>3:>Nil)[1,2,3]
NB: Not synthesisable
v :: Lift a => [a] -> ExpQ Source
Create a vector literal from a list literal
$(v [1::Signed 8,2,3,4,5]) == (8:>2:>3:>4:>5:>Nil) :: Vec 5 (Signed 8)
>>>[1 :: Signed 8,2,3,4,5][1,2,3,4,5]>>>$(v [1::Signed 8,2,3,4,5])<1,2,3,4,5>
lazyV :: KnownNat n => Vec n a -> Vec n a Source
For when your vector functions are too strict in their arguments
For example:
-- Bubble sort for 1 iteration
sortV xs = map fst sorted <: (snd (last sorted))
where
lefts = head xs :> map snd (init sorted)
rights = tail xs
sorted = zipWith compareSwapL lefts rights
-- Compare and swap
compareSwapL a b = if a < b then (a,b)
else (b,a)Will not terminate because zipWith is too strict in its second argument:
>>>sortV (4 :> 1 :> 2 :> 3 :> Nil)<*** Exception: <<loop>>
In this case, adding lazyV on zipWiths second argument:
sortVL xs = map fst sorted <: (snd (last sorted))
where
lefts = head xs :> map snd (init sorted)
rights = tail xs
sorted = zipWith compareSwapL (lazyV lefts) rights
Results in a successful computation:
>>>sortVL (4 :> 1 :> 2 :> 3 :> Nil)<1,2,3,4>
NB: There is also a solution using flip, but it slightly obfuscates the
meaning of the code:
sortV_flip xs = map fst sorted <: (snd (last sorted))
where
lefts = head xs :> map snd (init sorted)
rights = tail xs
sorted = zipWith (flip compareSwapL) rights lefts
>>>sortV_flip (4 :> 1 :> 2 :> 3 :> Nil)<1,2,3,4>