Hi,
I have a mutate function for a genetic algorithm which is giving me
odd results. I suspect I'm missing somthing really simple, so I'd be
grateful for any suggestions. Basically, when I comment out the line
which is commented out below, it works fine (although of course it
doesn't change the genome). When I uncomment it gen[letter]
automagically gets the value base in the print statements, before the
assignment has been made. And it still doesn't update the genome.
Genome is a string of integers in the range 0- 3, hence the
conversion.
def Mutate(self, mrate):
g = Random(rseed)
# If no mutation rate specified, use 1 per genome
if mrate == -1:
mrate = 1.0/len(self.genome)
print "mrate is ", mrate
print "original genome: "
print self.genome
# convert genome to a list
gen = [ord(letter)-48 for letter in self.genome]
for letter in range(len(gen)):
rnum = g.random()
if rnum < mrate:
base = g.randint(0,3)
print "base is ", base
print "pos ", letter, gen[letter], " to ", base
# gen[letter] = base
# convert list back to a string
self.genome = ''.join([str(x) for x in gen])
print "final genome"
print self.genome
Output with line commented out:
base is 1
pos 40 0 to 1
base is 0
pos 185 2 to 0
base is 3
pos 223 0 to 3
...etc
Output with line included:
base is 1
pos 40 1 to 1
base is 0
pos 185 0 to 0
base is 3
pos 223 3 to 3
Thanks,
Jen
--
http://mail.python.org/mailman/listinfo/python-list
