gistfile1.py

# takes an organism and returns a copy that may be mutated
def copy_and_mutate(organism):

	# first, make a copy
	new_organism = list(organism); 

	# to start the mutation action, define events and their string constants
	letter_change = 'LETTER_CHANGE'
	letter_deletion = 'LETTER_DELETION'
	insert_space = 'INSERT_SPACE'

	# define probabilities for mutation events 
	event_probabilities = {
		letter_change: config.LETTER_CHANGE_CHANCE,
		letter_deletion: config.LETTER_DELETION_CHANCE,
		insert_space: config.INSERT_SPACE_CHANCE
	}

	# iterate over the organism, allow mutations to happen
	for i,c in enumerate(new_organism):
		event = roll_weighted_die(event_probabilities)

		if event == letter_change:
			#print event
			new_organism[i] = random.choice(config.POSSIBLE_CHARACTERS)

		if event == insert_space:
			#print event
			new_organism.insert(i,' ')

		if event == letter_deletion:
			#print event
			del new_organism[i]
	return new_organism