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Haskell module for working with genetic algorithms
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GA, a Haskell library for working with genetic algorithms

version 0.2, Sept. 2011, written by Kenneth Hoste (


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 
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 (see evolveChkpt). 


Building the supplied examples can be done by running 'make'
in the examples directory after the installation of the GA library.

Using the GA module should be clear after studying the examples.


This release includes two toy examples that show how to use the GA module.

A first example evolves the string "Hello World!". The string that the
genetic algorithm should generate is supplied by the user in this example,
which is of course not representative of a real world problem that could 
be solved using genetic algorithms. However, it does serve well as a toy 

The code in example1.hs illustrates how you can define the "genRandom", 
"crossover", "mutation" and "score'" functions that are required to run 
the genetic algorithm using the 'evolve' function.

It also shows the use of a 'pool' that can be used to generate random
entities (a list of characters, in this particular case), and user-supplied
data that can be used to evaluate the fitness of entities (in this case,
the string "Hello World!").

The second example (see example2.hs) evolves an integer number that has
8 integer divisors, and for which the sum of its divisors equals 96.
Although using a genetic algorithm is probably not the best way to find 
such an integer (it would be easier/faster to just go over integer values
one by one starting from e.g. 8), but again, it serves well as a toy example.

This example shows how the pool and score data do not have to be used; it
suffices to supply '()' as values to the evolve function, and to simply ignore
the respective arguments passed to the Entity typeclass functions.

The third example reimplements the first example, but inside the IO monad.
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