-- Hoogle documentation, generated by Haddock
-- See Hoogle, http://www.haskell.org/hoogle/


-- | Genetic algorithm library
--   
--   This package provides a framework for working with genetic algorithms.
--   A genetic algorithm is an evolutionary technique, inspired by
--   biological evolution, to evolve entities that perform as good as
--   possible in terms of a predefined criterion (the scoring function).
--   Note: lower scores are assumed to indicate better entities. The GA
--   module provides a type class for defining entities and the functions
--   that are required by the genetic algorithm. Checkpointing in between
--   generations is available, as is automatic restoring from the last
--   available checkpoint.
@package GA
@version 0.1


-- | GA, a Haskell library for working with genetic algoritms
--   
--   Aug. 2011, by Kenneth Hoste
--   
--   version: 0.1
module GA

-- | Type class for entities that represent a candidate solution.
--   
--   Three parameters:
--   
--   <ul>
--   <li>data structure representing an entity (a)</li>
--   <li>data used to score an entity, e.g. a list of numbers (b)</li>
--   <li>some kind of pool used to generate random entities, e.g. a Hoogle
--   database (c)</li>
--   </ul>
class (Eq a, Read a, Show a, ShowEntity a) => Entity a b c | a -> b, a -> c
genRandom :: Entity a b c => c -> Int -> a
crossover :: Entity a b c => c -> Float -> Int -> a -> a -> Maybe a
mutation :: Entity a b c => c -> Float -> Int -> a -> Maybe a
score :: Entity a b c => a -> b -> Double

-- | Configuration for genetic algorithm.
data GAConfig
GAConfig :: Int -> Int -> Int -> Float -> Float -> Float -> Float -> Bool -> GAConfig

-- | population size
popSize :: GAConfig -> Int

-- | size of archive (best entities so far)
archiveSize :: GAConfig -> Int

-- | maximum number of generations to evolve
maxGenerations :: GAConfig -> Int

-- | fraction of entities generated by crossover (tip: &gt;= 0.80)
crossoverRate :: GAConfig -> Float

-- | fraction of entities generated by mutation (tip: &lt;= 0.20)
mutationRate :: GAConfig -> Float

-- | parameter for crossover (semantics depend on actual crossover
--   operator)
crossoverParam :: GAConfig -> Float

-- | parameter for mutation (semantics depend on actual mutation operator)
mutationParam :: GAConfig -> Float

-- | enable/disable built-in checkpointing mechanism
withCheckpointing :: GAConfig -> Bool

-- | Type class for pretty printing an entity instead of just using the
--   default show implementation.
class ShowEntity a
showEntity :: ShowEntity a => a -> String

-- | Do the evolution!
evolve :: Entity a b c => StdGen -> GAConfig -> c -> b -> IO a