ansaurus

Question

Answer 1

A:

I see you didn't declare position in the outer scope at all. Declare position before the function declarations, and you should be ok.

Marcin 2010-07-30 16:44:09

Yup, I've defined 'position' as global in the 'pickmonster' function.I should also point out that I do have definitions for all those monster variables, I just omitted them here as they're pretty long dictionary items.

Tom 2010-07-30 16:47:25

I tried that actually. I tried declaring 'position' as "" or 0 before the function, and it runs error free, but then it doesn't assign a new value to 'P01', it just makes "P01" equal whatever I first declared 'position' as.

Tom 2010-07-30 16:50:05

You need both, position declaration in front of the function, and the `global` inside the function.

Marcin 2010-07-30 16:52:30

Answer 2

+4 A:

There is several problems in the code. Like you are not calling function if it is not followed by opening and closing parenthesis.

ie: not slotseeder but slotseeder()

(That is the one that breaks the code)

I would probably write your sample code as below:

### Monster Statistics ####

default_stats = dict(name='unknown',
                 HP=[0, 0, 0, 0],
                 Atk1=[0, 0, 0, 0], Atk1dmg=[0, 0, 0, 0],
                 Atk2=[0, 0, 0, 0], Atk2dmg=[0, 0, 0, 0],
                 Atk3=[0, 0, 0, 0], Atk3dmg=[0, 0, 0, 0],
                 Dfns=[0, 0, 0, 0])

Monsters = [dict(default_stats, name='Cerebus'),
            dict(default_stats, name='Cthulhu'),
            dict(default_stats, name='Cyclops',
                 HP=[65, 85, 95, 130],
                 Atk1=[3, 4, 4, 5], Atk1dmg=[3, 4, 4, 5],
                 Atk2=[2, 3, 3, 4], Atk2dmg=[5, 6, 6, 7],
                 Atk3=[1, 2, 3, 3], Atk3dmg=[5, 6, 6, 7],
                 Dfns=[2, 3, 4, 5]),
            dict(default_stats, name='Genie'),
            dict(default_stats, name='Giant Ape',
                 HP=[70, 90, 110, 140],
                 Atk1=[3, 4, 4, 5], Atk1dmg=[4, 5, 5, 6],
                 Atk2=[2, 2, 3, 4], Atk2dmg=[5, 6, 6, 7],
                 Atk3=[1, 2, 3, 3], Atk3dmg=[6, 6, 7, 8],
                 Dfns=[2, 3, 3, 4]),
            dict(default_stats, name='Giant Lizard',
                 HP=[80, 100, 130, 170],
                 Atk1=[3, 3, 4, 5], Atk1dmg=[3, 4, 5, 6],
                 Atk2=[2, 3, 3, 4], Atk2dmg=[4, 5, 6, 7],
                 Atk3=[1, 2, 2, 3], Atk3dmg=[6, 7, 8, 8],
                 Dfns=[1, 2, 2, 3]),
            dict(default_stats, name='Grey Alien',
                 HP=[30, 40, 45, 50],
                 Atk1=[3, 3, 4, 5], Atk1dmg=[1, 2, 2, 3],
                 Atk2=[2, 2, 3, 4], Atk2dmg=[2, 3, 3, 4],
                 Atk3=[1, 2, 3, 4], Atk3dmg=[4, 5, 5, 6],
                 Dfns=[3, 4, 4, 5]),
            dict(default_stats, name='Gryffin'),
            dict(name='Leprechaun',
                HP=[30, 35, 50, 65],
                Atk1=[3, 4, 4, 5], Atk1dmg=[1, 1, 2, 3],
                Atk2=[2, 3, 4, 5], Atk2dmg=[2, 2, 3, 4],
                Atk3=[1, 2, 3, 4], Atk3dmg=[4, 5, 6, 6],
                Dfns=[4, 6, 7, 8]),
            dict(default_stats, name='Medusa',
                 HP=[20, 30, 45, 50],
                 Atk1=[3, 3, 4, 4], Atk1dmg=[1, 2, 2, 3],
                 Atk2=[2, 2, 3, 4], Atk2dmg=[2, 2, 3, 3],
                 Atk3=[1, 1, 2, 3], Atk3dmg=[4, 5, 5, 6],
                 Dfns=[2, 3, 4, 4]),
            dict(default_stats, name='Minotaur'),
            dict(default_stats, name='Ninja',
                 HP=[20, 30, 40, 55],
                 Atk1=[4, 5, 5, 7], Atk1dmg=[1, 2, 3, 3],
                 Atk2=[3, 4, 5, 6], Atk2dmg=[3, 4, 5, 6],
                 Atk3=[2, 2, 3, 3], Atk3dmg=[4, 5, 5, 6],
                 Dfns=[4, 5, 6, 7]),
            dict(default_stats, name='Ogre'),
            dict(default_stats, name='Ooze Monster',
                 HP=[30, 40, 60, 90],
                 Atk1=[4, 5, 6, 7], Atk1dmg=[1, 1, 2, 3],
                 Atk2=[2, 2, 3, 3], Atk2dmg=[2, 2, 3, 3],
                 Atk3=[1, 1, 2, 2], Atk3dmg=[4, 4, 6, 7],
                 Dfns=[1, 2, 3, 3]),
            dict(default_stats, name='Orc'),
            dict(default_stats, name='Pirate',
                 HP=[20, 30, 40, 45],
                 Atk1=[4, 5, 5, 6], Atk1dmg=[2, 3, 3, 4],
                 Atk2=[2, 2, 3, 4], Atk2dmg=[3, 3, 4, 5],
                 Atk3=[2, 3, 3, 4], Atk3dmg=[3, 4, 5, 6],
                 Dfns=[3, 4, 4, 5]),
            dict(default_stats, name='Possessed Doll'),
            dict(default_stats, name='Robot',
                HP=[63, 76, 84, 102],
                Atk1=[4, 5, 5, 6], Atk1dmg=[1, 2, 2, 3],
                Atk2=[3, 4, 4, 5], Atk2dmg=[2, 3, 3, 4],
                Atk3=[2, 2, 3, 3], Atk3dmg=[3, 4, 5, 5],
                Dfns=[2, 3, 4, 4]),
            dict(default_stats, name='Sasquatch'),
            dict(name='Unicorn',
                 HP=[25, 35, 50, 85],
                 Atk1=[3, 4, 4, 5], Atk1dmg=[2, 2, 3, 4],
                 Atk2=[3, 4, 5, 6], Atk2dmg=[3, 4, 5, 5],
                 Atk3=[2, 3, 4, 5], Atk3dmg=[4, 5, 6, 7],
                 Dfns=[4, 5, 6, 7]),
            dict(default_stats, name='Vampire',
                 HP=[40, 50, 75, 95],
                 Atk1=[4, 5, 5, 6], Atk1dmg=[1, 2, 2, 3],
                 Atk2=[2, 3, 3, 4], Atk2dmg=[2, 3, 4, 4],
                 Atk3=[1, 2, 2, 3], Atk3dmg=[3, 4, 5, 5],
                 Dfns=[3, 4, 5, 6]),
            dict(default_stats, name='Werewolf',
                HP=[25, 30, 50, 75],
                Atk1=[4, 4, 5, 6], Atk1dmg=[1, 2, 3, 3],
                Atk2=[3, 3, 4, 5], Atk2dmg=[2, 3, 3, 3],
                Atk3=[1, 1, 2, 4], Atk3dmg=[4, 4, 5, 6],
                Dfns=[4, 5, 6, 7]),
            dict(default_stats, name='Witch'),
            dict(default_stats, name='Wizard',
                 HP=[40, 60, 90, 115],
                 Atk1=[3, 3, 4, 5], Atk1dmg=[1, 1, 2, 2],
                 Atk2=[2, 3, 4, 4], Atk2dmg=[4, 4, 5, 6],
                 Atk3=[1, 1, 3, 3], Atk3dmg=[4, 5, 5, 6],
                 Dfns=[4, 5, 6, 6]),
            dict(default_stats, name='Yeti',
                 HP=[30, 35, 55, 80],
                 Atk1=[3, 4, 4, 5], Atk1dmg=[1, 2, 3, 4],
                 Atk2=[2, 2, 3, 4], Atk2dmg=[3, 3, 4, 5],
                 Atk3=[1, 1, 2, 3], Atk3dmg=[4, 5, 5, 6],
                 Dfns=[3, 3, 4, 5]),
            dict(default_stats, name='Zombie',
                 HP=[49, 60, 90, 120],
                 Atk1=[3, 3, 4, 5], Atk1dmg=[1, 2, 2, 3],
                 Atk2=[2, 2, 3, 4], Atk2dmg=[2, 3, 4, 4],
                 Atk3=[1, 1, 2, 3], Atk3dmg=[3, 4, 4, 5],
                 Dfns=[1, 2, 2, 3])
    ]

import random

picked = [monster for monster in Monsters 
          if monster['name'] in ['Cyclops',
                                 'Genie', 'Giant Ape', 'Giant Lizard',
                                 'Grey Alien', 'Leprechaun', 'Medusa',
                                 'Ninja', 'Ooze Monster', 'Pirate',
                                 'Robot', 'Unicorn', 'Vampire',
                                 'Werewolf', 'Wizard', 'Zombie']]

def slotseeder ():
    randomnumber = (random.randrange(0,len(picked)))
    if picked[randomnumber] != None:
        pickedmonster = Monsters[randomnumber]
        picked[randomnumber] = None
        return pickedmonster

P01 = slotseeder()
if P01 is not None:
    print "I got monster:", P01
else:
    print "Monster already used"

As you can see, the main change is in the data structure.

put all the monsters in one unique list. There is no point in using a different variable name for each. It just makes code harder to write when you want to pick a monster later.
I changed the dict initialisation syntax, the other one uses too much quotes for my taste.
also added default dictionary, it is handy to show which monsters are really defined or not, could also be used as template if some monsters are close enough.
replaced lists of numbered variables (like HP1, HP2, HP3, etc) with real lists. That's what lists are designed for. That slightly change access syntax, but it opens new possibilities. The same kind of change can probably be done for Atk levels as there is also numbered variables, but names suggests also that Atk1 and Atk1dmg may be combined as a tuple. I leave it to reader to still enhance the structure.

I believe the result is much easier to read than the initial one.

That is just a possibility. Another one could be to use a dictionary with monster name as key for all monsters. It would probably be even better than the above, and also defining a real Monster class would probably be a better idea than using dict(). But one step every day is enough.

After changing the data structure, changes to code are easy. I leave you figure it out. Just one last detail about initial program: it would never got a Zombie (because of randrange behavior). I figured it was a bug and changed it.

Have fun with python :-)

note: If you wonder if I really edited the monstruous initial structure, the answer is no. I wrote a program to do it for me. Well, I used some inline Perl for that purpose as it was faster than writing it using Python. I know. I'm evil.

kriss 2010-07-30 16:48:43

Boom. You nailed it. Thanks a lot. I'm a bit of a Python/programming noob. Working perfectly now. Thanks!

Tom 2010-07-30 16:52:18

Answer 3

+1 A:

May I suggest writing the ifs as something like:

monsters = [Cyclops, Genie, GiantApe, GiantLizard, GreyAlien, Leprechaun, Medusa, Ninja, OozeMonster, Pirate, Robot, Unicorn, Vampire, Werewolf, Wizard, Zombie]
monster = monsters[randomnumber-1]

DiggyF 2010-07-30 16:56:38

Thanks, that's a much nicer way to do it. My biggest problem right now is trying to discard random numbers that have already been chosen.My code up there is an attempt, but isn't really working. I'm appending the picked numbers into the 'pickednumbers' variable, and I can check if a value is in that variable, but I don't really know how to keep picking random numbers until I find one that hasn't been picked.I really want to do a 'while randomnumbers is not in pickednumbers' loop, but it doesn't seem to like it.

Tom 2010-07-30 17:20:57

you could do `randomnumbers = random.shuffle(range(16))` followed by `randomnumbers.pop()`. Or if you want to draw numbers from a larger population you could also use `random.sample()`.

DiggyF 2010-07-30 18:03:38

Answer 4

A:

To use a global variable, first create it globally (outside of all classes and functions), then declare it as global locally (with global keyword) so you can assign to it.

Here's a shortened version of your code that does it right:

>>> Cyclops = "data for Cyclops"
... position = "" # declares position in global scope
... def pickmonster ():
...     global position # tells python that the local variable 'position' refers to the global 'position'
...     position = Cyclops
... pickmonster()
... print position
data for Cyclops

Do note that use of global variables is generally frowned upon. It would be better to have the function pickmonster return the data you need and keep track of it locally.

Steven Rumbalski 2010-07-30 18:26:46

ansaurus

tags:

views:

answers:

Global Variable Not Defined

related questions