| Copyright | (C) 2010-2015 Maximilian Bolingbroke 2015-2019 Oleg Grenrus |
|---|---|
| License | BSD-3-Clause (see the file LICENSE) |
| Maintainer | Oleg Grenrus <oleg.grenrus@iki.fi> |
| Safe Haskell | Safe |
| Language | Haskell2010 |
Algebra.Lattice
Description
In mathematics, a lattice is a partially ordered set in which every two elements have a unique supremum (also called a least upper bound or join) and a unique infimum (also called a greatest lower bound or meet).
In this module lattices are defined using meet and join operators, as it's constructive one.
Synopsis
- class Lattice a where
- joinLeq :: (Eq a, Lattice a) => a -> a -> Bool
- joins1 :: (Lattice a, Foldable1 f) => f a -> a
- meetLeq :: (Eq a, Lattice a) => a -> a -> Bool
- meets1 :: (Lattice a, Foldable1 f) => f a -> a
- class Lattice a => BoundedJoinSemiLattice a where
- bottom :: a
- class Lattice a => BoundedMeetSemiLattice a where
- top :: a
- joins :: (BoundedJoinSemiLattice a, Foldable f) => f a -> a
- meets :: (BoundedMeetSemiLattice a, Foldable f) => f a -> a
- fromBool :: BoundedLattice a => Bool -> a
- type BoundedLattice a = (BoundedMeetSemiLattice a, BoundedJoinSemiLattice a)
- newtype Meet a = Meet {
- getMeet :: a
- newtype Join a = Join {
- getJoin :: a
- lfp :: (Eq a, BoundedJoinSemiLattice a) => (a -> a) -> a
- lfpFrom :: (Eq a, BoundedJoinSemiLattice a) => a -> (a -> a) -> a
- unsafeLfp :: (Eq a, BoundedJoinSemiLattice a) => (a -> a) -> a
- gfp :: (Eq a, BoundedMeetSemiLattice a) => (a -> a) -> a
- gfpFrom :: (Eq a, BoundedMeetSemiLattice a) => a -> (a -> a) -> a
- unsafeGfp :: (Eq a, BoundedMeetSemiLattice a) => (a -> a) -> a
Unbounded lattices
class Lattice a where Source #
An algebraic structure with joins and meets.
See http://en.wikipedia.org/wiki/Lattice_(order) and http://en.wikipedia.org/wiki/Absorption_law.
Lattice is very symmetric, which is seen from the laws:
Associativity
x\/(y\/z) ≡ (x\/y)\/z x/\(y/\z) ≡ (x/\y)/\z
Commutativity
x\/y ≡ y\/x x/\y ≡ y/\x
Idempotency
x\/x ≡ x x/\x ≡ x
Absorption
a\/(a/\b) ≡ a a/\(a\/b) ≡ a
Instances
joinLeq :: (Eq a, Lattice a) => a -> a -> Bool Source #
The partial ordering induced by the join-semilattice structure
joins1 :: (Lattice a, Foldable1 f) => f a -> a Source #
The join of at a list of join-semilattice elements (of length at least one)
meets1 :: (Lattice a, Foldable1 f) => f a -> a Source #
The meet of at a list of meet-semilattice elements (of length at least one)
Bounded lattices
class Lattice a => BoundedJoinSemiLattice a where Source #
A join-semilattice with an identity element bottom for \/.
Laws
x\/bottom≡ x
Corollary
x/\bottom≡⟨ identity ⟩ (x/\bottom)\/bottom≡⟨ absorption ⟩bottom
Instances
class Lattice a => BoundedMeetSemiLattice a where Source #
A meet-semilattice with an identity element top for /\.
Laws
x/\top≡ x
Corollary
x\/top≡⟨ identity ⟩ (x\/top)/\top≡⟨ absorption ⟩top
Instances
joins :: (BoundedJoinSemiLattice a, Foldable f) => f a -> a Source #
The join of a list of join-semilattice elements
meets :: (BoundedMeetSemiLattice a, Foldable f) => f a -> a Source #
The meet of a list of meet-semilattice elements
type BoundedLattice a = (BoundedMeetSemiLattice a, BoundedJoinSemiLattice a) Source #
Monoid wrappers
Monoid wrapper for meet-Lattice
Instances
| Monad Meet Source # | |
| Functor Meet Source # | |
| Applicative Meet Source # | |
| MonadZip Meet Source # | |
| Bounded a => Bounded (Meet a) Source # | |
| Eq a => Eq (Meet a) Source # | |
| Data a => Data (Meet a) Source # | |
Defined in Algebra.Lattice Methods gfoldl :: (forall d b. Data d => c (d -> b) -> d -> c b) -> (forall g. g -> c g) -> Meet a -> c (Meet a) # gunfold :: (forall b r. Data b => c (b -> r) -> c r) -> (forall r. r -> c r) -> Constr -> c (Meet a) # toConstr :: Meet a -> Constr # dataTypeOf :: Meet a -> DataType # dataCast1 :: Typeable t => (forall d. Data d => c (t d)) -> Maybe (c (Meet a)) # dataCast2 :: Typeable t => (forall d e. (Data d, Data e) => c (t d e)) -> Maybe (c (Meet a)) # gmapT :: (forall b. Data b => b -> b) -> Meet a -> Meet a # gmapQl :: (r -> r' -> r) -> r -> (forall d. Data d => d -> r') -> Meet a -> r # gmapQr :: forall r r'. (r' -> r -> r) -> r -> (forall d. Data d => d -> r') -> Meet a -> r # gmapQ :: (forall d. Data d => d -> u) -> Meet a -> [u] # gmapQi :: Int -> (forall d. Data d => d -> u) -> Meet a -> u # gmapM :: Monad m => (forall d. Data d => d -> m d) -> Meet a -> m (Meet a) # gmapMp :: MonadPlus m => (forall d. Data d => d -> m d) -> Meet a -> m (Meet a) # gmapMo :: MonadPlus m => (forall d. Data d => d -> m d) -> Meet a -> m (Meet a) # | |
| Ord a => Ord (Meet a) Source # | |
| Read a => Read (Meet a) Source # | |
| Show a => Show (Meet a) Source # | |
| Generic (Meet a) Source # | |
| Lattice a => Semigroup (Meet a) Source # | |
| BoundedMeetSemiLattice a => Monoid (Meet a) Source # | |
| Universe a => Universe (Meet a) Source # | |
Defined in Algebra.Lattice | |
| Finite a => Finite (Meet a) Source # | |
Defined in Algebra.Lattice | |
| (Eq a, Lattice a) => PartialOrd (Meet a) Source # | |
| type Rep (Meet a) Source # | |
Defined in Algebra.Lattice | |
Monoid wrapper for join-Lattice
Instances
| Monad Join Source # | |
| Functor Join Source # | |
| Applicative Join Source # | |
| MonadZip Join Source # | |
| Bounded a => Bounded (Join a) Source # | |
| Eq a => Eq (Join a) Source # | |
| Data a => Data (Join a) Source # | |
Defined in Algebra.Lattice Methods gfoldl :: (forall d b. Data d => c (d -> b) -> d -> c b) -> (forall g. g -> c g) -> Join a -> c (Join a) # gunfold :: (forall b r. Data b => c (b -> r) -> c r) -> (forall r. r -> c r) -> Constr -> c (Join a) # toConstr :: Join a -> Constr # dataTypeOf :: Join a -> DataType # dataCast1 :: Typeable t => (forall d. Data d => c (t d)) -> Maybe (c (Join a)) # dataCast2 :: Typeable t => (forall d e. (Data d, Data e) => c (t d e)) -> Maybe (c (Join a)) # gmapT :: (forall b. Data b => b -> b) -> Join a -> Join a # gmapQl :: (r -> r' -> r) -> r -> (forall d. Data d => d -> r') -> Join a -> r # gmapQr :: forall r r'. (r' -> r -> r) -> r -> (forall d. Data d => d -> r') -> Join a -> r # gmapQ :: (forall d. Data d => d -> u) -> Join a -> [u] # gmapQi :: Int -> (forall d. Data d => d -> u) -> Join a -> u # gmapM :: Monad m => (forall d. Data d => d -> m d) -> Join a -> m (Join a) # gmapMp :: MonadPlus m => (forall d. Data d => d -> m d) -> Join a -> m (Join a) # gmapMo :: MonadPlus m => (forall d. Data d => d -> m d) -> Join a -> m (Join a) # | |
| Ord a => Ord (Join a) Source # | |
| Read a => Read (Join a) Source # | |
| Show a => Show (Join a) Source # | |
| Generic (Join a) Source # | |
| Lattice a => Semigroup (Join a) Source # | |
| BoundedJoinSemiLattice a => Monoid (Join a) Source # | |
| Universe a => Universe (Join a) Source # | |
Defined in Algebra.Lattice | |
| Finite a => Finite (Join a) Source # | |
Defined in Algebra.Lattice | |
| (Eq a, Lattice a) => PartialOrd (Join a) Source # | |
| type Rep (Join a) Source # | |
Defined in Algebra.Lattice | |
Fixed points of chains in lattices
lfp :: (Eq a, BoundedJoinSemiLattice a) => (a -> a) -> a Source #
Implementation of Kleene fixed-point theorem http://en.wikipedia.org/wiki/Kleene_fixed-point_theorem. Forces the function to be monotone.
lfpFrom :: (Eq a, BoundedJoinSemiLattice a) => a -> (a -> a) -> a Source #
Implementation of Kleene fixed-point theorem http://en.wikipedia.org/wiki/Kleene_fixed-point_theorem. Forces the function to be monotone.
unsafeLfp :: (Eq a, BoundedJoinSemiLattice a) => (a -> a) -> a Source #
Implementation of Kleene fixed-point theorem http://en.wikipedia.org/wiki/Kleene_fixed-point_theorem. Assumes that the function is monotone and does not check if that is correct.
gfp :: (Eq a, BoundedMeetSemiLattice a) => (a -> a) -> a Source #
Implementation of Kleene fixed-point theorem http://en.wikipedia.org/wiki/Kleene_fixed-point_theorem. Forces the function to be antinone.
gfpFrom :: (Eq a, BoundedMeetSemiLattice a) => a -> (a -> a) -> a Source #
Implementation of Kleene fixed-point theorem http://en.wikipedia.org/wiki/Kleene_fixed-point_theorem. Forces the function to be antinone.
unsafeGfp :: (Eq a, BoundedMeetSemiLattice a) => (a -> a) -> a Source #
Implementation of Kleene fixed-point theorem http://en.wikipedia.org/wiki/Kleene_fixed-point_theorem. Assumes that the function is antinone and does not check if that is correct.