[Python][문법] 기초 - 5. Class 1

#!/usr/bin/env python

# coding: utf-8

# # 1. 객체지향 프로그래밍(Class) I

# ### 1.1 객체와 클래스

# - 클래스

# - 인스턴스

# - 객체(object)

# In[ ]:

class Car:

    def __init__(self):

        self._speed = 0

        print('자동차가 생성되었습니다.')

    def get_speed(self):

        return self._speed

    def start(self):

        self._speed = 20

        print('자동차가 출발합니다.')

    def accelerate(self):

        self._speed = self._speed + 30

        print('자동차가 가속합니다.')

    def stop(self):

        self._speed = 0

        print('자동차가 정지합니다.')

# main

my_car = Car()

my_car.start()

print('속도 1: ', my_car.get_speed() )

my_car.accelerate()

print('속도 2: ', my_car.get_speed() )

my_car.stop()

print('속도 3: ', my_car.get_speed() )

# ### 1.2 self

# In[ ]:

class Car:

    def __init__(self):

        self._speed = 0

    def get_speed(self):

        return self._speed

    def start(self):

        self._speed = 20

    def accelerate(self):

        self._speed = self._speed + 30

    def stop(self):

        self._speed = 0

# main

my_car1 = Car()

my_car2 = Car()

my_car1.start()

my_car2.start()

my_car1.accelerate()

my_car2.accelerate()

my_car2.accelerate()

print('첫번째 자동차 속도: ', my_car1.get_speed() )

print('두번째 자동차 속도: ', my_car2.get_speed() )

my_car1.stop()

my_car2.stop()

# In[ ]:

class Radio:

    def __init__(self):

        print('라디오가 생성되었습니다.')

        pass

    def turn_on(self):

        print('라디오를 켭니다')

       

    def turn_off(self):

        print('라디오를 끕니다')

class Car:

    def __init__(self):

        self._speed = 0

        print('자동차가 생성되었습니다.')

        self._radio = Radio()

    def get_speed(self):

        return self._speed

    def start(self):

        self._speed = 20

        print('자동차가 출발합니다.')

    def accelerate(self):

        self._speed = self._speed + 30

        print('자동차가 가속합니다.')

    def stop(self):

        self._speed = 0

        print('자동차가 정지합니다.')

    def turn_on_radio(self):

        self._radio.turn_on()

    def turn_off_radio(self):

        self._radio.turn_off()

# main

my_car = Car()

my_car.start()

my_car.turn_on_radio()

my_car.accelerate()

my_car.turn_off_radio()

my_car.stop()

# ### 1.3 모듈과 클래스

# #### vehicle.py

#

# ```python

#

# def change_km_to_mile(km):

#     return km * 0.621371

#

# def change_mile_to_km(mile):

#     return mile * 1.609344

#

#

# class Car:

#     def __init__(self):

#         self._speed = 0

#

#     def get_speed(self):

#         return self._speed

#

#     def start(self):

#         self._speed = 20

#

#     def accelerate(self):

#         self._speed = self._speed + 30

#

#     def stop(self):

#         self._speed = 0

#

# class Truck:

#     def __init__(self):

#         self._speed = 0

#

#     def get_speed(self):

#         return self._speed

#

#     def start(self):

#         self._speed = 10

#

#     def accelerate(self):

#         self._speed = self._speed + 20

#

#     def stop(self):

#         self._speed = 0

#

#

# if __name__ == '__main__':

#     my_car = Car()

#     my_car.start()

#     my_car.accelerate()

#     print('속도: ', my_car.get_speed() )

#     my_car.stop()

# ```

# In[ ]:

import vehicle

#import vehicle as vh

#from vehicle import *

my_car = vehicle.Car()

#my_car = vh.Car()

#my_car = Car()

my_car.start()

my_car.accelerate()

speed_mile = vehicle.change_km_to_mile(my_car.get_speed())

#speed_mile = vh.change_km_to_mile(my_car.get_speed())

#speed_mile = change_km_to_mile(my_car.get_speed())

print('속도: ', speed_mile, 'mile' )

my_car.stop()

# ### 1.4 클래스와 데이터 타입

# In[ ]:

type(1)

type(3.14)

isinstance(1, int)

type('Hello World')

isinstance('Hello World', str)

type([1,2,3])

isinstance([1,2,3], list)

type({'line':1, 'rectangle':2, 'triangle':3})

isinstance({'line':1, 'rectangle':2, 'triangle':3}, dict)

# In[ ]:

from vehicle import *

my_car = Car()

type(my_car)

isinstance(my_car, Car)

my_truck = Truck()

type(my_truck)

isinstance(my_truck, Truck)

# ### 1.5 캡슐화와 접근지정

# - 캡슐화(encapsulation)

# - 상속성(inheritance)

# - 다형성(polymorphism)

# In[ ]:

# access_modifiers1

class Car:

    def __init__(self):

        self.price = 2000

        self._speed = 0

        self.__color = 'red'

my_car = Car()

print(my_car.price)

print(my_car._speed)

print(my_car.__color)

# In[ ]:

# access_modifiers2

class Car:

    def __init__(self):

        self._price = 0

        self._speed = 0

        self._color = None

    def get_price(self):

        return self._price

    def set_price(self, value):

        self._price = value

    def get_speed(self):

        return self._speed

    def set_speed(self, value):

        self._speed = value

    def get_color(self):

        return self._color

    def set_color(self, value):

        self._color = value

# main

my_car = Car()

my_car.set_price(2000)

my_car.set_speed(20)

my_car.set_color('red')

print('가격: ', my_car.get_price())

print('속도: ', my_car.get_speed())

print('색상: ', my_car.get_color())

# ### 1.6 property 이용하기

# In[ ]:

# car_property1

class Car:

    def __init__(self):

        self._price = 0

        self._speed = 0

        self._color = None

    @property

    def price(self):

        return self._price

       

    @price.setter

    def price(self, value):

        self._price = value

    @property

    def speed(self):

        return self._speed

    @speed.setter

    def speed(self, value):

        self._speed = value

    @property

    def color(self):

        return self._color

    @color.setter

    def color(self, value):

        self._color = value

# main

my_car = Car()

my_car.price = 2000

my_car.speed = 20

my_car.color = 'red'

print('가격: ', my_car.price)

print('속도: ', my_car.speed)

print('색상: ', my_car.color)

# In[ ]:

# car_property2

class Car:

    def __init__(self):

        self._price = 0

        self._speed = 0

        self._color = None

    def get_price(self):

        return self._price

       

    def set_price(self, value):

        self._price = value

   

    price = property(get_price, set_price)

    def get_speed(self):

        return self._speed

    def set_speed(self, value):

        self._speed = value

    speed = property(get_speed, set_speed)

   

    def get_color(self):

        return self._color

    def set_color(self, value):

        self._color = value

       

    color = property(get_color, set_color)

# main

my_car = Car()

my_car.price = 2000

my_car.speed = 20

my_car.color = 'red'

print('가격: ', my_car.price)

print('속도: ', my_car.speed)

print('색상: ', my_car.color)

# ### 1.7 예제: 요일 구하기(객체지향)

# In[ ]:

# 년월일을 입력받는 함수

# 반환값: 년월일을 튜플형태로 반환

def input_date():

    year  = int(input('년도를 입력하시오: '))

    month = int(input('월을 입력하시오: '))

    day   = int(input('일을 입력하시오: '))

   

    return year, month, day

# In[ ]:

# DayName 클래스

class DayName(object):

    # DayName 클래스 생성자

    def __init__(self, year, month, day):

        self._year  = year

        self._month = month

        self._day   = day

        self._name  = None

       

        self._year_month_days = [0,31,28,31,30,31,30,31,31,30,31,30,31]

        self._day_names = ['일요일','월요일','화요일','수요일','목요일','금요일','토요일']

       

        # 요일을 계산한다

        self._calculate_day_name()

       

    # 윤년인지를 체크하는 메서드

    def _is_leap(self, year):

        if year % 400 == 0:                 # 400으로 나뉘는 해: 윤년

            return True

        elif year % 100 == 0:               # 100으로 나뉘는 해: 평년

            return False

        elif year % 4 == 0:                 # 4으로 나뉘는 해  : 윤년

            return True

        else:

            return False

   

    # 요일을 계산하는 메서드

    def _calculate_day_name(self):

   

        total_days = 0

       

        for item in range(1, self._year):

            if self._is_leap(item):

                total_days = total_days + 366

            else:

                total_days = total_days + 365

        for item in range(1, self._month):

            total_days = total_days + self._year_month_days[item]

        if month >= 3:

            if self._is_leap(self._year):

                total_days = total_days + 1

        total_days += self._day

        remainder = total_days % 7

       

        self._name = self._day_names[remainder]

   

    # 요일 이름을 반환하는 메서드

    def get_name(self):

        return self._name

   

# In[ ]:

# main

year, month, day = input_date()

day_name = DayName(year, month, day)

print( day_name.get_name())

# ### 1.8 예제: 성적 처리 시스템(객체지향)

# In[ ]:

# student

class Student(object):

    def __init__(self, num, name, kor, eng, math):

   

        # 학생의 속성

        self._num  = num

        self._name = name

        self._kor  = kor

        self._eng  = eng

        self._math = math

       

        self._total = 0

        self._avg   = 0.0

        self._order = 0

       

        # 총점과 평균을 구한다.

        self._calculate_total()

        self._calculate_avg()

   

    def _calculate_total(self):

        self._total = self._kor + self._eng + self._math

       

    def _calculate_avg(self):

        self._avg = self._total / 3

   

    @property

    def num(self):

        return self._num

       

    @property

    def name(self):

        return self._name

       

    @property

    def kor(self):

        return self._kor

       

    @property

    def eng(self):

        return self._eng

       

    @property

    def math(self):

        return self._math

       

    @property

    def total(self):

        return self._total

       

    @property

    def avg(self):

        return self._avg

       

    @property

    def order(self):

        return self._order

       

    @order.setter

    def order(self, value):

        self._order = value

# In[ ]:

# grade_system

class StudentGradeSystem(object):

    def __init__(self):

   

        # 학생 객체를 저장할 리스트

        self._students = []

       

        # 반 성적을 저장할 속성

        self._class_avg = 0.0

        self._kor_avg   = 0.0

        self._eng_avg   = 0.0

        self._math_avg  = 0.0

    # 학생 등수를 구한다.

    def _calculate_student_order(self):

        temp_students = sorted(self._students, key = lambda x: x.total, reverse = True)

       

        order = 1

        for student in temp_students:

            student.order = order

            order = order + 1

           

        self._students = temp_students

   

    # 반 평균을 구한다.

    def _calculate_class_avg(self):

        total = 0

       

        for student in self._students:

            total = total + student.total

       

        self._class_avg = total / len(self._students)

    # 국어 평균을 구한다.

    def _calculate_kor_avg(self):

        total = 0

       

        for student in self._students:

            total = total + student.kor

       

        self._kor_avg = total / len(self._students)

    # 영어 평균을 구한다.

    def _calculate_eng_avg(self):

        total = 0

       

        for student in self._students:

            total = total + student.eng

       

        self._eng_avg = total / len(self._students)

    # 수학 평균을 구한다.

    def _calculate_math_avg(self):

        total = 0

       

        for student in self._students:

            total = total + student.math

       

        self._math_avg = total / len(self._students)

    # 반 성적 정보를 구한다.

    def _calculate_class_information(self):

        self._calculate_class_avg()

        self._calculate_kor_avg()

        self._calculate_eng_avg()

        self._calculate_math_avg()

    # 학생 객체를 등록한다.

    def register_student(self, student):

        self._students.append(student)

    # 학생 성적 및 반 성적을 처리한다.

    def process(self):

        self._calculate_student_order()         # 학생 순위를 구한다.

        self._calculate_class_information()     # 반 성적 정보를 구한다.

    # 학생 성적을 출력한다.

    def print_students(self):

        for student in self._students:

            print('번호: {:s}, 이름: {:s}, 국어: {:d}, 영어: {:d}, 수학: {:d}, 총점: {:d}, 평균: {:.2f}, 등수: {:d}'.format(

                   student.num, student.name,

                   student.kor, student.eng, student.math,

                   student.total, student.avg, student.order)

                 )

    # 반 성적 정보를 출력한다.

    def print_class_information(self):

        print('반 평균  : {:.2f}'.format(self._class_avg))

        print('국어 평균: {:.2f}'.format(self._kor_avg)  )

        print('영어 평균: {:.2f}'.format(self._eng_avg)  )

        print('수학 평균: {:.2f}'.format(self._math_avg) )

# In[ ]:

# main

student_grade_system = StudentGradeSystem()

student = Student('1', '김철수', 90, 80, 85)

student_grade_system.register_student(student)

student = Student('2', '박제동', 90, 85, 90)

student_grade_system.register_student(student)

student = Student('3', '홍길동', 80, 80, 80)

student_grade_system.register_student(student)

student_grade_system.process()

student_grade_system.print_students()

print()

student_grade_system.print_class_information()

# ---

# In[ ]:

# end of file

# In[ ]: