Safe Haskell | Safe-Infered |
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A module for doing arithmetic in permutation groups.

Group elements are represented as permutations of underlying sets, and are entered and displayed
using a Haskell-friendly version of cycle notation. For example, the permutation (1 2 3)(4 5)
would be entered as `p [[1,2,3],[4,5]]`

, and displayed as [[1,2,3],[4,5]]. Permutations can be defined
over arbitrary underlying sets (types), not just the integers.

If `g`

and `h`

are group elements, then the expressions `g*h`

and `g^-1`

calculate product and inverse respectively.

- rotateL :: [a] -> [a]
- newtype Permutation a = P (Map a a)
- p :: Ord a => [[a]] -> Permutation a
- fromPairs :: Ord a => [(a, a)] -> Permutation a
- fromPairs' :: Ord a => [(a, a)] -> Permutation a
- toPairs :: Permutation a -> [(a, a)]
- fromList :: Ord a => [a] -> Permutation a
- supp :: Permutation a -> [a]
- (.^) :: Ord a => a -> Permutation a -> a
- (-^) :: Ord a => [a] -> Permutation a -> [a]
- fromCycles :: Ord a => [[a]] -> Permutation a
- toCycles :: Ord a => Permutation a -> [[a]]
- cycleOf :: Ord a => Permutation a -> a -> [a]
- parity :: Ord a => Permutation a -> Int
- sign :: (Num a, Ord a1) => Permutation a1 -> a
- orderElt :: Ord a => Permutation a -> Int
- (~^) :: (Ord a, Show a) => Permutation a -> Permutation a -> Permutation a
- comm :: HasInverses a => a -> a -> a
- closureS :: Ord a => [a] -> [a -> a] -> Set a
- closure :: Ord a => [a] -> [a -> a] -> [a]
- orbit :: Ord a => (a -> t -> a) -> a -> [t] -> [a]
- (.^^) :: Ord a => a -> [Permutation a] -> [a]
- orbitP :: Ord a => [Permutation a] -> a -> [a]
- orbitV :: Ord a => [Permutation a] -> a -> [a]
- (-^^) :: Ord a => [a] -> [Permutation a] -> [[a]]
- orbitB :: Ord a => [Permutation a] -> [a] -> [[a]]
- orbitE :: Ord a => [Permutation a] -> [a] -> [[a]]
- action :: Ord a => [a] -> (a -> a) -> Permutation a
- orbits :: Ord a => [Permutation a] -> [[a]]
- _C :: Integral a => a -> [Permutation a]
- _D :: Integral a => a -> [Permutation a]
- _D2 :: Integral a => a -> [Permutation a]
- _S :: Integral a => a -> [Permutation a]
- _A :: Integral a => a -> [Permutation a]
- dp :: (Ord a, Ord b) => [Permutation a] -> [Permutation b] -> [Permutation (Either a b)]
- wr :: (Ord t, Ord t1) => [Permutation t] -> [Permutation t1] -> [Permutation (t, t1)]
- toSn :: (Enum a, Num a, Ord a, Ord k) => [Permutation k] -> [Permutation a]
- fromDigits :: (Num a, Ord a) => Permutation [a] -> Permutation a
- fromDigits' :: Num a => [a] -> a
- fromBinary :: (Num a, Ord a) => Permutation [a] -> Permutation a
- fromBinary' :: Num a => [a] -> a
- elts :: (Num a, Ord a) => [a] -> [a]
- eltsS :: (Num a, Ord a) => [a] -> Set a
- order :: (Num a, Ord a) => [a] -> Int
- isMember :: (Num a, Ord a) => [a] -> a -> Bool
- minsupp :: Permutation c -> c
- orderTGS :: (Num a1, Ord a, Show a) => [Permutation a] -> a1
- eltsTGS :: (Ord a, Show a) => [Permutation a] -> [Permutation a]
- tgsFromSgs :: (Ord a, Show a) => [Permutation a] -> [Permutation a]
- orderSGS :: Ord a => [Permutation a] -> Integer
- gens :: (Num a, Ord a) => [a] -> [a]
- (~^^) :: (Ord a, Show a) => Permutation a -> [Permutation a] -> [Permutation a]
- conjClass :: (Ord a, Show a) => [Permutation a] -> Permutation a -> [Permutation a]
- conjClassReps :: (Ord a, Show a) => [Permutation a] -> [(Permutation a, Int)]
- reduceGens :: (Num a, Ord a) => [a] -> [a]
- isSubgp :: (Num a, Ord a) => [a] -> [a] -> Bool
- subgps :: (Ord a, Show a) => [Permutation a] -> [[Permutation a]]
- isMinimal :: (Ord a, Show a) => Permutation a -> Bool
- centralizer :: (Num t, Ord t) => [t] -> [t] -> [t]
- centre :: (Num t, Ord t) => [t] -> [t]
- normalizer :: (Ord a, Show a) => [Permutation a] -> [Permutation a] -> [Permutation a]
- stabilizer :: (Ord a, Show a) => [Permutation a] -> a -> [Permutation a]
- ptStab :: (Ord a, Show a) => [Permutation a] -> [a] -> [Permutation a]
- setStab :: (Ord a, Show a) => [Permutation a] -> [a] -> [Permutation a]
- normalClosure :: (Ord a, Show a) => [Permutation a] -> [Permutation a] -> [Permutation a]
- commutatorGp :: (Ord a, Show a) => [Permutation a] -> [Permutation a] -> [Permutation a]
- derivedSubgp :: (Ord a, Show a) => [Permutation a] -> [Permutation a]
- (-*-) :: (Num b, Ord b) => [b] -> [b] -> [b]
- (-*) :: (Num a, Ord a) => [a] -> a -> [a]
- (*-) :: (Num a, Ord a) => a -> [a] -> [a]
- isNormal :: (Ord a, Show a) => [Permutation a] -> [Permutation a] -> Bool
- normalSubgps :: (Ord a, Show a) => [Permutation a] -> [[Permutation a]]
- isSimple :: (Ord a, Show a) => [Permutation a] -> Bool
- cosets :: (Num t, Ord t) => [t] -> [t] -> [[t]]
- quotientGp :: (Ord a, Show a) => [Permutation a] -> [Permutation a] -> [Permutation Int]
- (//) :: (Ord a, Show a) => [Permutation a] -> [Permutation a] -> [Permutation Int]
- (~~^) :: (Ord a, Show a) => [Permutation a] -> Permutation a -> [Permutation a]
- conjugateSubgps :: (Ord a, Show a) => [Permutation a] -> [Permutation a] -> [[Permutation a]]
- subgpAction :: (Enum a1, Num a1, Ord a1, Ord a, Show a) => [Permutation a] -> [Permutation a] -> [Permutation a1]
- rrpr :: (Num a, Ord a) => [a] -> a -> Permutation a
- rrpr' :: (Num a, Ord a) => [a] -> a -> Permutation a
- permutationMatrix :: (Num t, Ord a) => [a] -> Permutation a -> [[t]]

# Documentation

newtype Permutation a Source

A type for permutations, considered as functions or actions which can be performed on an underlying set.

(Eq k, Num k) => HopfAlgebra k (Permutation Int) | |

(Eq k, Num k) => Bialgebra k (Permutation Int) | |

(Eq k, Num k) => Coalgebra k (Permutation Int) | |

(Eq k, Num k) => Algebra k (Permutation Int) | |

(Eq k, Num k) => Module k (Permutation Int) Int | |

Eq a => Eq (Permutation a) | |

(Ord a, Show a) => Num (Permutation a) | The Num instance is what enables us to write |

Ord a => Ord (Permutation a) | |

(Ord a, Show a) => Show (Permutation a) | |

Mon (Permutation Int) | |

(Ord a, Show a) => HasInverses (Permutation a) | The HasInverses instance is what enables us to write |

HasInverses (GroupAlgebra Q) | Note that the inverse of a group algebra element can only be efficiently calculated if the group generated by the non-zero terms is very small (eg <100 elements). |

p :: Ord a => [[a]] -> Permutation aSource

Construct a permutation from a list of cycles.
For example, `p [[1,2,3],[4,5]]`

returns the permutation that sends 1 to 2, 2 to 3, 3 to 1, 4 to 5, 5 to 4.

fromPairs :: Ord a => [(a, a)] -> Permutation aSource

fromPairs' :: Ord a => [(a, a)] -> Permutation aSource

toPairs :: Permutation a -> [(a, a)]Source

fromList :: Ord a => [a] -> Permutation aSource

supp :: Permutation a -> [a]Source

(.^) :: Ord a => a -> Permutation a -> aSource

x .^ g returns the image of a vertex or point x under the action of the permutation g.
For example, `1 .^ p [[1,2,3]]`

returns 2.
The dot is meant to be a mnemonic for point or vertex.

(-^) :: Ord a => [a] -> Permutation a -> [a]Source

b -^ g returns the image of an edge or block b under the action of the permutation g.
For example, `[1,2] -^ p [[1,4],[2,3]]`

returns [3,4].
The dash is meant to be a mnemonic for edge or line or block.

fromCycles :: Ord a => [[a]] -> Permutation aSource

toCycles :: Ord a => Permutation a -> [[a]]Source

cycleOf :: Ord a => Permutation a -> a -> [a]Source

parity :: Ord a => Permutation a -> IntSource

sign :: (Num a, Ord a1) => Permutation a1 -> aSource

orderElt :: Ord a => Permutation a -> IntSource

(~^) :: (Ord a, Show a) => Permutation a -> Permutation a -> Permutation aSource

g ~^ h returns the conjugate of g by h, that is, h^-1*g*h. The tilde is meant to a mnemonic, because conjugacy is an equivalence relation.

comm :: HasInverses a => a -> a -> aSource

(.^^) :: Ord a => a -> [Permutation a] -> [a]Source

x .^^ gs returns the orbit of the point or vertex x under the action of the gs

orbitP :: Ord a => [Permutation a] -> a -> [a]Source

orbitV :: Ord a => [Permutation a] -> a -> [a]Source

(-^^) :: Ord a => [a] -> [Permutation a] -> [[a]]Source

b -^^ gs returns the orbit of the block or edge b under the action of the gs

orbitB :: Ord a => [Permutation a] -> [a] -> [[a]]Source

orbitE :: Ord a => [Permutation a] -> [a] -> [[a]]Source

action :: Ord a => [a] -> (a -> a) -> Permutation aSource

orbits :: Ord a => [Permutation a] -> [[a]]Source

_C :: Integral a => a -> [Permutation a]Source

_C n returns generators for Cn, the cyclic group of order n

_D :: Integral a => a -> [Permutation a]Source

_D2 :: Integral a => a -> [Permutation a]Source

_S :: Integral a => a -> [Permutation a]Source

_S n returns generators for Sn, the symmetric group on [1..n]

_A :: Integral a => a -> [Permutation a]Source

_A n returns generators for An, the alternating group on [1..n]

dp :: (Ord a, Ord b) => [Permutation a] -> [Permutation b] -> [Permutation (Either a b)]Source

Given generators for groups H and K, acting on sets A and B respectively, return generators for the direct product H*K, acting on the disjoint union A+B (= Either A B)

wr :: (Ord t, Ord t1) => [Permutation t] -> [Permutation t1] -> [Permutation (t, t1)]Source

toSn :: (Enum a, Num a, Ord a, Ord k) => [Permutation k] -> [Permutation a]Source

fromDigits :: (Num a, Ord a) => Permutation [a] -> Permutation aSource

fromDigits' :: Num a => [a] -> aSource

fromBinary :: (Num a, Ord a) => Permutation [a] -> Permutation aSource

fromBinary' :: Num a => [a] -> aSource

elts :: (Num a, Ord a) => [a] -> [a]Source

Given generators for a group, return a (sorted) list of all elements of the group. Implemented using a naive closure algorithm, so only suitable for small groups (|G| < 10000)

order :: (Num a, Ord a) => [a] -> IntSource

Given generators for a group, return the order of the group (the number of elements). Implemented using a naive closure algorithm, so only suitable for small groups (|G| < 10000)

minsupp :: Permutation c -> cSource

eltsTGS :: (Ord a, Show a) => [Permutation a] -> [Permutation a]Source

tgsFromSgs :: (Ord a, Show a) => [Permutation a] -> [Permutation a]Source

orderSGS :: Ord a => [Permutation a] -> IntegerSource

Given a strong generating set, return the order of the group it generates

(~^^) :: (Ord a, Show a) => Permutation a -> [Permutation a] -> [Permutation a]Source

conjClass :: (Ord a, Show a) => [Permutation a] -> Permutation a -> [Permutation a]Source

conjClassReps :: (Ord a, Show a) => [Permutation a] -> [(Permutation a, Int)]Source

conjClassReps gs returns conjugacy class representatives and sizes for the group generated by gs. This implementation is only suitable for use with small groups (|G| < 10000).

reduceGens :: (Num a, Ord a) => [a] -> [a]Source

subgps :: (Ord a, Show a) => [Permutation a] -> [[Permutation a]]Source

Return the subgroups of a group. Only suitable for use on small groups (eg < 100 elts)

centralizer :: (Num t, Ord t) => [t] -> [t] -> [t]Source

normalizer :: (Ord a, Show a) => [Permutation a] -> [Permutation a] -> [Permutation a]Source

stabilizer :: (Ord a, Show a) => [Permutation a] -> a -> [Permutation a]Source

ptStab :: (Ord a, Show a) => [Permutation a] -> [a] -> [Permutation a]Source

setStab :: (Ord a, Show a) => [Permutation a] -> [a] -> [Permutation a]Source

normalClosure :: (Ord a, Show a) => [Permutation a] -> [Permutation a] -> [Permutation a]Source

commutatorGp :: (Ord a, Show a) => [Permutation a] -> [Permutation a] -> [Permutation a]Source

derivedSubgp :: (Ord a, Show a) => [Permutation a] -> [Permutation a]Source

isNormal :: (Ord a, Show a) => [Permutation a] -> [Permutation a] -> BoolSource

isNormal gs ks returns True if <ks> is normal in <gs>. Note, it is caller's responsibility to ensure that <ks> is a subgroup of <gs> (ie that each k is in <gs>).

normalSubgps :: (Ord a, Show a) => [Permutation a] -> [[Permutation a]]Source

Return the normal subgroups of a group. Only suitable for use on small groups (eg < 100 elts)

quotientGp :: (Ord a, Show a) => [Permutation a] -> [Permutation a] -> [Permutation Int]Source

quotientGp gs ks returns <gs> / <ks>

(//) :: (Ord a, Show a) => [Permutation a] -> [Permutation a] -> [Permutation Int]Source

Synonym for quotientGp

(~~^) :: (Ord a, Show a) => [Permutation a] -> Permutation a -> [Permutation a]Source

conjugateSubgps :: (Ord a, Show a) => [Permutation a] -> [Permutation a] -> [[Permutation a]]Source

subgpAction :: (Enum a1, Num a1, Ord a1, Ord a, Show a) => [Permutation a] -> [Permutation a] -> [Permutation a1]Source

rrpr :: (Num a, Ord a) => [a] -> a -> Permutation aSource

rrpr' :: (Num a, Ord a) => [a] -> a -> Permutation aSource

permutationMatrix :: (Num t, Ord a) => [a] -> Permutation a -> [[t]]Source