[8일차] ASAC 빅데이터 분석가 4기(Python기초-5)

⚙️ Python

📌 상속

• 부모가 가진 속성들을 자식이 물려받는 개념
• 자식은 자신만의 속성을 추가로 가질 수 있다.

class Parent(object):
    def __init__(self):
        self.money = '$1M'

    def speech(self):
        print('천리길도 한 걸음씩')

class Child(Parent): # 상속받는 클래스
    def __init__(self):
        pass

class Puppy(object): # 상속받지 않는 클래스
    def __init__(self):
        pass

---

📌 lambda의 활용

• 두 lambda식을 한 줄로 이용하기

ff = lambda x: lambda y: x+y
print(ff(1)(2))

---

📌 중첩 함수

• 두개의 함수를 중첩하여 사용할 수 있다.

def f(x):
    def g(y):
        return x + y
    return g

g = f(1)
print(g(2))

def some_func(f): # 고차 함수
    y = f('chanwoo')
    return y

def input_func(x):
    return "hello world " + x

print(some_func(input_func)) # input 함수를 사용하는 경우

print(some_func(lambda x : "hello world " + x)) # input 함수 대신 lambda식을 이용하는 경우

---

📌 map

• 주어진 리스트에 대해 동일한 처리를 수행하여 반환해준다.

list(map(lambda x:x+1, [1,2,3,4]))

---

📌 filter

• 주어진 리스트에 대해 조건을 만족하는 결과를 필터링 해준다.

list(filter(lambda x: x>2, [1,2,3,4,5,6,7]))

---

📌 reduce

• 주어진 초기값부터 시작하여 리스트의 각 원소에 대한 함수 연산 결과를 누적해준다.

from functools import reduce

# ((((((0 + 1) + 2) + 3) + 3) + 5) + 6) -> 20
reduce(lambda x, y : x + y, [1,2,3,3,5,6], 0)

---

⚙️ 실습

📝 격투 게임 만들기

💡 클래스를 사용하여 간단한 격투 게임을 만들어보자

class Fighter(object):
    def __init__(self, name, martial_arts, hp, punch_damage, kick_damage):
        self.name = name
        self.martial_arts = martial_arts
        self.hp = hp
        self.punch_damage = punch_damage
        self.kick_damage = kick_damage

    def punch(self, object):
        if object.name == self.name:
            print("Cannot attack yourself!")
        else:
            if self.hp > 0:
                if object.hp > 0:
                    object.hp -= self.punch_damage
                    print(f'HIT!!! {self.name} -> {object.name} - {self.punch_damage}')
                else:
                    print(f'{object.name} has already dead')
            else:
                print("You already dead. You can do nothing")

    def kick(self, object):
        if object.name == self.name:
            print("Cannot attack yourself!")
        else:
            if self.hp > 0:
                if object.hp > 0:
                    object.hp -= self.kick_damage
                    print(f'HIT!!! {self.name} -> {object.name} - {self.kick_damage}')
                else:
                    print(f'{object.name} has already dead')
            else:
                print("You already dead. You can do nothing")

    def get_info(self):
        state = 'alive' if self.hp > 0 else 'dead'

        info = f'''
        name : {self.name}
        martial_arts : {self.martial_arts}
        hp : {self.hp}
        state : {state}
        
        Attacking points
        punch : {self.punch_damage}
        kick : {self.kick_damage}
        '''

        print(info)

---

📝 격투 게임 만들기 2

💡 상속을 사용하여 더욱 체계화된 격투 게임을 만들어보자

class Character(object):
    def __init__(self, name):
        self.name = name
        self.hp = 100

    def punch(self, object):
        print("you cannot punch")

    def kick(self, object):
        print("you cannot kick")

    def staff(self, object):
        print("you cannot use staff")

    def magic(self, object):
        print("you cannot use magic")

    def get_magician_info(self):
        alive = 'alive' if self.hp > 0 else 'dead'

        info = f'''
        name: {self.name}
        HP: {self.hp}
        State: {alive}

        Attacking points
        Staff: {self.staff_damage}
        Magic: {self.magic_damage}
        '''
        print(info)

    def get_fighter_info(self):
        alive = 'alive' if self.hp > 0 else 'dead'

        info = f'''
        name: {self.name}
        martial arts: {self.martial_arts}
        HP: {self.hp}
        State: {alive}

        Attacking points
        Punch: {self.punch_damage}
        Kick: {self.kick_damage}
        '''
        print(info)

class Fighter(Character):
    def __init__(self, name, martial_arts, punch_damage, kick_damage):
        super().__init__(name = name)
        self.martial_arts = martial_arts
        self.punch_damage = punch_damage
        self.kick_damage = kick_damage

    def punch(self, object):
        if object.name == self.name:
            print("Cannot attack yourself!")
        else:
            if self.hp > 0:
                if object.hp > 0:
                    object.hp -= self.punch_damage
                    print(f'HIT!!! {self.name} -> {object.name} - {self.punch_damage}')
                else:
                    print(f'{object.name} has already dead')
            else:
                print("You already dead. You can do nothing")

    def kick(self, object):
        if object.name == self.name:
            print("Cannot attack yourself!")
        else:
            if self.hp > 0:
                if object.hp > 0:
                    object.hp -= self.kick_damage
                    print(f'HIT!!! {self.name} -> {object.name} - {self.kick_damage}')
                else:
                    print(f'{object.name} has already dead')
            else:
                print("You already dead. You can do nothing")

class Magician(Character):
    def __init__(self, name, martial_arts, staff_damage, magic_damage):
        super().__init__(name = name)
        self.martial_arts = martial_arts
        self.staff_damage = staff_damage
        self.magic_damage = magic_damage

    def staff(self, object):
        if object.name == self.name:
            print("Cannot attack yourself!")
        else:
            if self.hp > 0:
                if object.hp > 0:
                    object.hp -= self.staff_damage
                    print(f'HIT! {self.name} -> {object.name} -{self.staff_damage}')
                else:
                    print(f'{object.name} has already dead')
            else:
                print(f'{object.name} has already dead')

    def magic(self, object):
        if object.name == self.name:
            print("Cannot attack yourself!")
        else:
            if self.hp > 0:
                if object.hp > 0:
                    object.hp -= self.magic_damage
                    print(f'MAGIC!! {self.name} -> {object.name} -{self.magic_damage}')
                else:
                    print(f'{object.name} has already dead')
            else:
                print(f'{object.name} has already dead')

---

📝 재귀 함수 만들기

💡 중첩 함수를 재귀 함수로 만들어보자

def call_something(f, xs):
    new_xs = []
    for x in xs:
        new_xs.append(f(x))
    return new_xs

def call_rec(f, xs):
    if not xs:
        return []
    h, *t = xs
    return [f(h)] + call_rec(f,t)

---

📝 재귀 함수 만들기 2

💡 filter 연산을 재귀 함수로 만들어보자

def filter_rec(f, xs):
    if not xs:
        return []
    h, *t = xs

    if f(h):
        return [h] + filter_rec(f, t)
    else:
        return filter_rec(f, t)