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a couple of things I don't understand wrt lists

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hello,

I am a beginner programmer. I started learning programming about a year and a
half ago, using C. I picked up python a few months ago, but only wrote very few
scripts.

I am currently trying to learn more about the python way of doing things by
writing a script that generates png images using a 1D cellular automaton.

While writing preliminary code for that project, I ran into a behaviour that I
don't understand.
I am using python 2.7 on a linux system.

I represent the CA's rule with a list of integers, of value 1 or 0.
Here is the function I use to generate the list:

def get_rule(rulenum):
  rule = []
  while rulenum > 0:
    rule.append(rulenume % 2)
    rulenum /= 2
  while len(rule) < 8:
    rule.append(0)
  rule.reverse()
  return rule

if i call it by writing:

rule = getrule(int(8))

and then call:

print rule

the output is good:

[0, 0, 0, 0, 1, 0, 0, 0]


I then tried to print each item of the list using a for loop:

for i in range(rule):
  print rule[i]

the output is, as expected:
0
0
0
0
1
0
0
0

but when I do:

for i in rule:
  print rule[i]

I get the "complement":
1
1
1
1
0
1
1
1

There must be something I didn't understand correctly in the for statement, but
I really can't think of a reason why the output is what it is.
I tried this using the interactive console, and the results are the same,
whatever the length of the list, i always get the complement of my bit pattern.

Any pointers to help me understand this would be appreciated.
I am also running into an other issue with this script, but I'd rather
understand this before asking further questions.

Thanks, and sorry for the rather long post.

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a couple of things I don't understand wrt lists aaB <mecagonoisician@gmail.com> - 2013-04-16 17:37 +0200
  Re: a couple of things I don't understand wrt lists John Gordon <gordon@panix.com> - 2013-04-16 16:43 +0000
  Re: a couple of things I don't understand wrt lists Larry Hudson <orgnut@yahoo.com> - 2013-04-16 21:57 -0700
    Re: a couple of things I don't understand wrt lists Serhiy Storchaka <storchaka@gmail.com> - 2013-04-17 12:35 +0300
      Re: a couple of things I don't understand wrt lists 88888 Dihedral <dihedral88888@googlemail.com> - 2013-04-17 09:10 -0700
        Re: a couple of things I don't understand wrt lists Ned Batchelder <ned@nedbatchelder.com> - 2013-04-17 14:36 -0400
          Re: a couple of things I don't understand wrt lists Steven D'Aprano <steve+comp.lang.python@pearwood.info> - 2013-04-18 04:46 +1000
        Re: a couple of things I don't understand wrt lists Chris Angelico <rosuav@gmail.com> - 2013-04-18 04:42 +1000
      Re: a couple of things I don't understand wrt lists 88888 Dihedral <dihedral88888@googlemail.com> - 2013-04-17 09:10 -0700

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