genetic algorithm snippet.py

i=0 
fitness = 0 
counter = 0 
while i < max_iter: 
   if counter > n_repeats: 
      STOP 
   Y = [ ]
   fit = [ ] 
   pairs = randompairsfrom (X) 
   for j in pairs: 
      y = crossover ( j )
      y = randommutation ( y )
      Y. append (y)
      fit.append (fitness(y))
   Y, fit = ordermaxtomin (Y, fit ) 
   bestfitness = fit[ 0 ]
   if bestfitness < fitness: 
      counter = counter+1
   else: 
      counter = 0
      X = Y [0: N] 
      i=i+1 
      fitness = bestfitness