Framework for writing evolutionary optimization algorithms in OCaml
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GenePool is a framework for writing evolutionary optimization algorithms in OCaml. This library is not a complete solution but rather is a generic skeleton which takes care of the plumbing and nuisances of optimization. You provide GenePool with functions that give meaning to fitness and reproduction and after a specified number of generation, GenePool returns an array of the best "genomes" it evolved.

The interface to GenePool is extremely simple. It consists of a single function evolve whose type is:

    ('genome, 'fitness) ga_spec -> ga_params -> 'genome array * 'fitness

As you can tell from the signature, GenePool is polymorphic over both the representation of the genome and the type of fitness values. Typically your genome will be an array and fitness will be expressed as either an int or float. However, nothing stops you from using different types if your problem requires them. The first parameter is a record (of type ga_spec) which encodes how evolution will proceed for your specific problem.

    GA Specification
        evaluate  - assign a fitness to a genome
        mutatate  - given a genome, create an altered copy
        crossover - given two genomes, combine them
        genRandom - produce a random genome from scratch
        seed      - optional initial seed population
        report    - optional function to output information 
                    about the best genome of each generation 
        stop      - optional stopping predicate

type ('genome, 'fitness) ga_spec = {
  evaluate : 'genome -> 'fitness;
  mutate : 'genome -> 'genome;
  crossover : 'genome * 'genome -> 'genome;
  genRandom: unit -> 'genome;
  seed: 'genome array option;
  report: (int -> 'genome -> 'fitness -> unit) option;
  stop: (int > 'genome -> 'fitness -> bool) option

Some parameters (ie, the maximum number of generations, the number of genomes which survive each generations, etc...) are universal across all optimization algorithms. These are provided in another record, whose type is ga_params.

    GA Parameters
    nRandom - how many random genomes should we generate at the beginning
    nSurvivors - how many genomes survive of each generation 
    nMutations - # genomes generated by asexual reproduction each generation
    nCrossovers - # genomes by sexual reproduction each generation 
    timeLimit - seconds until algorithm termination 
    maxGen - maximum number of generations until algorithm termination 

type ga_params = {
  nRandom: int;
  nSurvivors: int;
  nMutations: int;
  nCrossovers: int;
  maxGen: int