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I just started learning python so I'm not familiar with the various tricks or tools, or the proper way to word my question. Because of that, I was unable to find previous questions that do what I am looking for.

I have a working code outlined here:

import random



class UserGroup:

    def __init__(self, users):

        self.user_list = users



    def random_users(self):

        self.random_1 = random.choice(self.user_list)

        self.random_2 = self.random_1

        while self.random_2 == self.random_1:

            self.random_2 = random.choice(self.user_list)

        return self.random_1, self.random_2



class User:

    def __init__(self, nickname, stats):

        self.nickname = nickname

        self.strength = stats['strength']

        self.constitution = stats['constitution']

        self.dexterity = stats['dexterity']

        self.intelligence = stats['intelligence']

        self.wisdom = stats['wisdom']

        self.charisma = stats['charisma']



    def __repr__(self):

        return self.nickname



class Jared(User):

    def fight_stat(self):

        self.attack = self.strength + self.intelligence

        self.defense = self.constitution * 2

        self.speed = self.dexterity / 2



class Poptart(User):

    def fight_stat(self):

        self.attack = self.strength + self.dexterity

        self.defense = self.dexterity

        self.speed = self.dexterity + self.charisma



class Kaos(User):

    def fight_stat(self):

        self.attack = self.dexterity + self.wisdom

        self.defense = self.wisdom * 2

        self.speed = self.dexterity



class Magda(User):

    def fight_stat(self):

        self.attack = self.intelligence + self.charisma

        self.defense = self.dexterity + self.charisma

        self.speed = self.dexterity + self.constitution / 2



class Battle:

    def __init__(self, user1, user2):

        self.user1 = user1

        self.user2 = user2

        print(user1, "and", user2, "have entered the fight!")



    def fight(self):

        self.user1.fight_stat()

        self.user2.fight_stat()

        if self.user1.speed > self.user2.speed:

            self.attacker = self.user1

            self.defender = self.user2

        elif self.user2.speed > self.user1.speed:

            self.attacker = self.user2

            self.defender = self.user1

        elif self.user1.dexterity > self.user2.dexterity:

            self.attacker = self.user1

            self.defender = self.user2

        else: 

            self.attacker = self.user2

            self.defender = self.user1

        if self.attacker.attack > self.defender.defense:

            return self.attacker

        elif self.defender.attack > self.attacker.defense:

            return self.defender

        else:

            return "Draw"



# HERE STARTS BATTLE CODE

jared = Jared('Jarebear', {'strength': 7, 'constitution': 6, 'dexterity': 6, 'intelligence': 8, 'wisdom': 5, 'charisma': 5})

poptart = Poptart('Yung SLizzy', {'strength': 4, 'constitution': 5, 'dexterity': 10, 'intelligence': 7, 'wisdom': 5, 'charisma': 7})

kaos = Kaos('Kung Cows', {'strength': 8, 'constitution': 7, 'dexterity': 6, 'intelligence': 4, 'wisdom': 7, 'charisma': 4})

magda = Magda('Meghan M', {'strength': 7, 'constitution': 5, 'dexterity': 7, 'intelligence': 8, 'wisdom': 5, 'charisma': 5})



users = UserGroup([jared, poptart, kaos, magda])



for i in range(1,4):

    print("Battle number", i)

    battle = Battle(*users.random_users())

    print("The winner is: ", battle.fight())

The example output is shown below:

Battle number 1

Jarebear and Kung Cows have entered the fight!

The winner is:  Kung Cows

Battle number 2

Jarebear and Kung Cows have entered the fight!

The winner is:  Kung Cows

Battle number 3

As I have written it, the code performs as expected. However, I am concerned about the way that I've implemented the fight() method inside the Battle class. I don't think the large sequence of if statements is the proper way to say "user with higher speed attacks first". Logically, I just need a statement that is like self.attacker = max(self.user1.speed, self.user2.speed) but the attacker is set to the user, not the user's speed. However, I don't know how to accomplish this in one or two lines of code in python.

Creating small methods that concentrate logic is no "overhead". They are easy to understand, and do not need to change for lots of reasons - hence they are done, testet and unchanged most of the time.

class Battle:



    # snipped some code    



    @staticmethod

    def get_attacker_defender(u1, u2):

        """Returs tuple (attacker,defender) based on given user."""

        if u1.speed > u2.speed:

            return u1,u2

        elif u2.speed > u1.speed:

            return u2,u1

        # probably cleaner to stay with elif: ... else ... but this is shorter

        return (u1,u2) if u1.dexterity > u2.dexterity else (u2,u1)





    def fight(self):

        self.user1.fight_stat()

        self.user2.fight_stat()

        self.attacker, self.defender = Battle.get_attacker_defender(self.user1,self.user2)



        if self.attacker.attack > self.defender.defense:

            return self.attacker

        elif self.defender.attack > self.attacker.defense:

            return self.defender

        else:

            return "Draw"

If you like a brain teaser you could as well do:

@staticmethod

def get_attacker_defender(u1,u2):

    return sorted( [u1,u2], key = lambda u:(u.speed,u.dexterity), reverse=True)

which leverages tuple-sorting that sorts based on the 1st element, and when the 1st ones are equal on the 2nd element of the tuple. If both are equal the order stays as is (stable sorting with Timsort).

Doku:

• 
  Does Python have a ternary conditional operator? (for return .. if ... else ...)


• sorted(... with key and reversed ...)


• Why are Python lambdas useful?

The min and max functions accept a key function that tells them how to compare the inputs. The key accepts each input and returns the actual value to compare:

max(self.user1, self.user2, key=lambda item: item.speed)

For a large number of comparisons, this can be rewritten as

from operator import attrgetter



speed_key = attrgetter('speed')

max(self.user1, self.user2, key=speed_key)

If you have equal speeds, you can decide to compare using a different attribute. This is done by understanding that Python sequences are compared in lexicographixal order. This is easiest to understand with strings, since it's basically just dictionary order: e.g. 'abc' > 'abb' because each element is compared in order. The same applies to lists and tuples: [1, 2, 3] > [1, 2, 2].

So to use the dexterity attribute as a fallback for equal speeds, do

max(self.user1, self.user2, key=lambda item: (item.speed, item.dexterity))

OR

speedex_key = attrgetter('speed', 'dexterity')

max(self.user1, self.user2, key=speedex_key)

If you want to use max with your objects, you can implement __gt__ com compare them (and __eq__ for consistency). So your User class could look like this:

class User:

    def __init__(self, nickname, stats):

        self.nickname = nickname

        self.strength = stats['strength']

        self.constitution = stats['constitution']

        self.dexterity = stats['dexterity']

        self.intelligence = stats['intelligence']

        self.wisdom = stats['wisdom']

        self.charisma = stats['charisma']



    def __repr__(self):

        return self.nickname



    def __eq__(self, other):

        return self.speed == other.speed and self.dexterity == other.dexterity



    def __gt__(self, other):

        return self.speed > other.speed or self.dexterity > other.dexterity

This implementation would allow you to use max and min to define the attacker and defender in the Battle class.

class Battle:

    def __init__(self, user1, user2):

        self.user1 = user1

        self.user2 = user2

        print(user1, "and", user2, "have entered the fight!")



    def fight(self):

        self.user1.fight_stat()

        self.user2.fight_stat()



        self.attacker = max(self.user1, self.user2)

        self.defender = min(self.user1, self.user2)



        if self.attacker.attack > self.defender.defense:

            return self.attacker

        elif self.defender.attack > self.attacker.defense:

            return self.defender

        else:

            return "Draw"

I just need a statement that is like self.attacker =
max(self.user1.speed, self.user2.speed) but the attacker is set to the
user, not the user's speed.

You can use

from operator import attrgetter

...

self.attacker = max(self.user1, self.user2, key=attrgetter('speed'))

This will return the user (not speed) has max speed

If you have more than 2 users, you can also pass list

More information about attrgetter

You can indeed use max() to get the user with most speed.

The way of doing it is with the keyargument which you use to pass a custom scoring function that takes each object and returns a orderable value like a float or int.

def score(user):

    return user.speed



fastest_user = max(list_of_users, key=score)

The most common is to pass an anonymous lambda function which you define with the syntax:

lambda var1, var2: expression

So the code would look like:

fastest_user = max(list_of_users, key=lambda user: user.speed)