re: http://spacecats.heroku.com/

gistfile2.rb

spacecats explorer

#!/usr/bin/env ruby
require 'rubygems'
require 'open-uri'

class SpaceCat

  attr_reader :weight, :limbs, :color
  attr_accessor :fitness

  def initialize(*traits)
    @weight, @limbs, @color, @fitness = *traits
  end

  def hexcolor
    ('%6s' % color.to_s(16)).gsub(' ', '0')
  end

  def self.random
    new rand(1000), rand(100), rand(0xffffff)
  end

  def mutate
    @weight += rand(10 * 2 + 1) - 10
    @weight = [[@weight, 1000].min, 1].max

    @limbs += rand(1 * 2 + 1) - 1
    @limbs = [[@limbs, 100].min, 0].max

    @color += rand(167772 * 2 + 1) - 167772
    @color = [[@color, 0xffffff].min, 0].max
  end

  def clone
    SpaceCat.new weight, limbs, color, fitness
  end

  def to_s
    '[' + [weight, limbs, hexcolor, fitness].join(' ') + ']'
  end

  def <=>(other)
    self.fitness.to_i <=> other.fitness.to_i
  end
end

class Galaxy < Struct.new :name

  def teleport(cats)
    traits = {}
    %w(weight limbs hexcolor).each do |trait|
      traits[trait.to_sym] = cats.map{|cat|cat.send trait}.join(',')
    end

    url = "http://spacecats.heroku.com/galaxies/#{name}" +
                  "?batch=true" +
                  "&weight=#{traits[:weight]}" +
                  "&limbs=#{traits[:limbs]}" +
                  "&color=#{traits[:hexcolor]}"
    fitnesses = open(url).read.split(',')
    #puts "#{url}: #{fitnesses.join(',')}"

    cats.each_index do |i|
      cats[i].fitness = fitnesses[i]
    end
  end

  def self.all
    @@all ||= open("http://spacecats.heroku.com/galaxies").read.split(',').
      map{|name| new(name)}
  end
end

class Exploration < Struct.new :galaxy, :cats, :cycles, :cutoff

  def run
    cycles.times do |trip|
      galaxy.teleport(cats)

      self.cats.sort!

      # eliminate bottom @cutoff underperformers
      self.cats.slice!(0, cutoff)

      # clone top @cutoff superperformers
      clones = cats.slice(-cutoff, cutoff).map{|cat| cat.clone}
      self.cats += clones

      puts "#{trip}: #{best_cat}: " +
        cats.slice(-20,20).map{|cat|cat.fitness}.join(',')

      cats.each{|cat| cat.mutate}
    end
  end

  def best_cat
    @best_cat ||= cats.last.dup
    @best_cat = [@best_cat, cats.last].max.dup
  end
end

galaxy = ARGV
size = 100
trips = 1000
crew = size.times.map{SpaceCat.random}
gal = Galaxy.new galaxy
e = Exploration.new gal, crew, trips, crew.size / 10
e.run