Safe Haskell	None
Language	Haskell98

Moo.GeneticAlgorithm.Run

Contents

Running algorithm
Iteration control

Description

Helper functions to run genetic algorithms and control iterations.

Synopsis

runGA :: Rand [Genome a] -> ([Genome a] -> Rand b) -> IO b
runIO :: Rand [Genome a] -> (IORef PureMT -> [Genome a] -> IO (Population a)) -> IO (Population a)
nextGeneration :: ObjectiveFunction objectivefn a => ProblemType -> objectivefn -> SelectionOp a -> Int -> CrossoverOp a -> MutationOp a -> StepGA Rand a
nextSteadyState :: ObjectiveFunction objectivefn a => Int -> ProblemType -> objectivefn -> SelectionOp a -> CrossoverOp a -> MutationOp a -> StepGA Rand a
makeStoppable :: (ObjectiveFunction objectivefn a, Monad m) => objectivefn -> (Population a -> m (Population a)) -> StepGA m a
loop :: Monad m => Cond a -> StepGA m a -> [Genome a] -> m (Population a)
loopWithLog :: (Monad m, Monoid w) => LogHook a m w -> Cond a -> StepGA m a -> [Genome a] -> m (Population a, w)
loopIO :: [IOHook a] -> Cond a -> StepGA Rand a -> IORef PureMT -> [Genome a] -> IO (Population a)
data Cond a
- = Generations Int
- | IfObjective ([Objective] -> Bool)
- | Eq b => GensNoChange {
  - c'maxgens :: Int
  - c'indicator :: [Objective] -> b
  - c'counter :: Maybe (b, Int)
  }
- | Or (Cond a) (Cond a)
- | And (Cond a) (Cond a)
data LogHook a m w where
- WriteEvery :: (Monad m, Monoid w) => Int -> (Int -> Population a -> w) -> LogHook a m w
data IOHook a
- = DoEvery {
  - io'n :: Int
  - io'action :: Int -> Population a -> IO ()
  }
- | StopWhen (IO Bool)
- | TimeLimit {
  - io't :: Double
  }

Running algorithm

runGA Source #

Arguments

:: Rand [Genome a]	function to create initial population
-> ([Genome a] -> Rand b)	genetic algorithm, see also `loop` and `loopWithLog`
-> IO b	final population

Helper function to run the entire algorithm in the Rand monad. It takes care of generating a new random number generator.

runIO Source #

Arguments

:: Rand [Genome a]	function to create initial population
-> (IORef PureMT -> [Genome a] -> IO (Population a))	genetic algorithm, see also `loopIO`
-> IO (Population a)	final population

Helper function to run the entire algorithm in the IO monad.

nextGeneration Source #

Arguments

:: ObjectiveFunction objectivefn a
=> ProblemType	a type of the optimization `problem`
-> objectivefn	objective function
-> SelectionOp a	selection operator
-> Int	`elite`, the number of genomes to keep intact
-> CrossoverOp a	crossover operator
-> MutationOp a	mutation operator
-> StepGA Rand a

Construct a single step of the genetic algorithm.

See Moo.GeneticAlgorithm.Binary and Moo.GeneticAlgorithm.Continuous for the building blocks of the algorithm.

nextSteadyState Source #

Arguments

:: ObjectiveFunction objectivefn a
=> Int	`n`, number of worst solutions to replace
-> ProblemType	a type of the optimization `problem`
-> objectivefn	objective function
-> SelectionOp a	selection operator
-> CrossoverOp a	crossover operator
-> MutationOp a	mutation operator
-> StepGA Rand a

Construct a single step of the incremental (steady-steate) genetic algorithm. Exactly n worst solutions are replaced with newly born children.

See Moo.GeneticAlgorithm.Binary and Moo.GeneticAlgorithm.Continuous for the building blocks of the algorithm.

makeStoppable :: (ObjectiveFunction objectivefn a, Monad m) => objectivefn -> (Population a -> m (Population a)) -> StepGA m a Source #

Wrap a population transformation with pre- and post-conditions to indicate the end of simulation.

Use this function to define custom replacement strategies in addition to nextGeneration and nextSteadyState.

Iteration control

loop Source #

Arguments

:: Monad m
=> Cond a	termination condition `cond`
-> StepGA m a	`step` function to produce the next generation
-> [Genome a]	initial population
-> m (Population a)	final population

Run strict iterations of the genetic algorithm defined by step. Return the result of the last step. Usually only the first two arguments are given, and the result is passed to runGA.

loopWithLog Source #

Arguments

:: (Monad m, Monoid w)
=> LogHook a m w	periodic logging action
-> Cond a	termination condition `cond`
-> StepGA m a	`step` function to produce the next generation
-> [Genome a]	initial population
-> m (Population a, w)	final population

GA iteration interleaved with the same-monad logging hooks. Usually only the first three arguments are given, and the result is passed to runGA.

loopIO Source #

Arguments

:: [IOHook a]	input-output actions, special and time-dependent stop conditions
-> Cond a	termination condition `cond`
-> StepGA Rand a	`step` function to produce the next generation
-> IORef PureMT	reference to the random number generator
-> [Genome a]	initial population `pop0`
-> IO (Population a)	final population

GA iteration interleaved with IO (for logging or saving the intermediate results); it takes and returns the updated random number generator via an IORef. Usually only the first three arguments are given, and the result is passed to runIO.

data Cond a Source #

Iterations stop when the condition evaluates as True.

Constructors

Generations Int	stop after `n` generations
IfObjective ([Objective] -> Bool)	stop when objective values satisfy the `predicate`
Eq b => GensNoChange	terminate when evolution stalls
Fields c'maxgens :: Int max number of generations for an indicator to be the same c'indicator :: [Objective] -> b stall indicator function c'counter :: Maybe (b, Int) a counter (initially `Nothing`)
Or (Cond a) (Cond a)	stop when at least one of two conditions holds
And (Cond a) (Cond a)	stop when both conditions hold

data LogHook a m w where Source #

Logging to run every nth iteration starting from 0 (the first parameter). The logging function takes the current generation count and population.

Constructors

WriteEvery :: (Monad m, Monoid w) => Int -> (Int -> Population a -> w) -> LogHook a m w

data IOHook a Source #

Input-output actions, interactive and time-dependent stop conditions.

Constructors

DoEvery	action to run every `n`th iteration, starting from 0; initially (at iteration 0) the objective value is zero.
Fields io'n :: Int io'action :: Int -> Population a -> IO ()
StopWhen (IO Bool)	custom or interactive stop condition
TimeLimit	terminate iteration after `t` seconds
Fields io't :: Double