Python基础学习

yum -y install zlib-devel bzip2-devel openssl-devel ncurses-devel sqlite-devel readline-devel tk-devel gdbm-devel db4-devel libpcap-devel xz-devel libffi-devel

# wget下载安装包并解压至 /usr/local/python3
wget https://www.python.org/ftp/python/3.7.0/Python-3.7.0.tgz
tar -C /usr/local -xzvf Python-3.7.0.tgz
cd /usr/local/Python-3.7.0

./configure --prefix=/usr/local/python3
make && make install

# 上面的参数，--prefix 是预期安装目录，--enable-optimizations 是优化选项（LTO，PGO 等）加上这个 flag 编译后，性能有 10% 左右的优化，但是这会明显的增加编译时间。
# 安装成功会提示如下消息:
Collecting setuptools
Collecting pip
Installing collected packages: setuptools, pip
Successfully installed pip-10.0.1 setuptools-39.0.1

ln -s /usr/local/python3/bin/python3.7 /usr/local/bin/python3
ln -s /usr/local/python3/bin/pip3.7 /usr/local/bin/pip3

#!/usr/local/bin/python3
# -*- coding:utf-8 -*-
for x in range(20):
    if x % 2 == 0:
        print(x)

name = 'Tom'
years = 1998
print('name = %s, Year = %d' % (name, years))
print(f'name = {name}, Year = {years}')

# 1. float() -- 转换成浮点型
num1 = 1
print(float(num1))
print(type(float(num1)))
# 2. str() -- 转换成字符串类型
num2 = 10
print(type(str(num2)))
# 3. tuple() -- 将⼀个序列转换成元组
list1 = [10, 20, 30]
print(tuple(list1))
print(type(tuple(list1)))
# 4. eval() -- 将字符串中的数据转换成Python表达式原本类型
str1 = '10'
str2 = '[1, 2, 3]'
str3 = '(1000, 2000, 3000)'
print(type(eval(str1)))
print(type(eval(str2)))
print(type(eval(str3)))

a = 0
b = 1
c = 2
# and运算符，只要有⼀个值为0，则结果为0，否则结果为最后⼀个⾮0数字
print(a and b)  # 0
print(b and c)  # 2
print(c and b)  # 1
# or运算符，只有所有值为0结果才为0，否则结果为第⼀个⾮0数字
print(a or b)  # 1
print(a or c)  # 2
print(b or c)  # 1

firstName = 'ada'
lastName = 'LOVER'
print(firstName.title() + ' ' + lastName.title())  # Ada Lover
print(firstName.upper())  # ADA
print(lastName.lower())  # lover

favoriteLan = ' python3 '
print(favoriteLan.lstrip())  # 'python3 '
print(favoriteLan.rstrip())  # ' python3'
print(favoriteLan.strip())  # 'python3'

favoriteLan = ' python3 '
print(favoriteLan.__len__())  # 9
print(len(favoriteLan))  # 9

cars = ['audi', 'bmw', 'subaru', 'toyota']

for car in cars:
    if car == 'bmw':
        print(car.upper())
    else:
        print(car.title())

cars = ['audi', 'bmw', 'subaru', 'toyota']
# and
if cars[0].lower() == 'audi' and cars[1] == 'bo':
    print(True)  # True
elif cars[1] == 'bmw':
    print(cars[1].title())  # Bmw
# in
print('audi' in cars)  # True
print('bo' in cars)  # False
# not in
print('bo' not in cars)  # True

bicycles = ['trek', 'cannondale', 'redline', 'speci']
print(bicycles)  # ['trek', 'cannondale', 'redline', 'speci']

# add
bicycles.append('hongqi')
print(bicycles)  # ['trek', 'cannondale', 'redline', 'speci', 'hongqi']
# insert
bicycles.insert(0,'beijing')
print(bicycles)  # ['beijing', 'trek', 'cannondale', 'redline', 'speci', 'hongqi']

bicycles = ['trek', 'redline', 'speci']
print(bicycles)  # ['trek', 'redline', 'speci']

del bicycles[0]
print(bicycles)  # ['redline', 'speci']

bics = bicycles.pop(1)
print(bics)  # redline
print(bicycles)  # ['trek', 'speci']
bicycles.pop()
print(bicycles)  # ['trek']

bicycles.remove('speci')
print(bicycles)  # ['trek', 'redline']

bicycles.sort()
print(bicycles)  # ['redline', 'speci', 'trek']
bicycles.sort(reverse=True)
print(bicycles)  # ['trek', 'speci', 'redline']

print(sorted(bicycles))
print(sorted(bicycles, reverse=True))

bicycles.reverse()
print(bicycles)  # ['speci', 'redline', 'trek']

numbers = [value ** 2 for value in range(1, 11)]
print(numbers)  # [1, 4, 9, 16, 25, 36, 49, 64, 81, 100]

numbers = [value ** 2 for value in range(1, 11)]
print(numbers)  # [1, 4, 9, 16, 25, 36, 49, 64, 81, 100]
print(numbers[0:2])  # [1, 4]
print(numbers[:4])  # [1, 4, 9, 16]
print(numbers[5:])  # [36, 49, 64, 81, 100]
print(numbers[-3:])  # [64, 81, 100]

numbers = [value ** 2 for value in range(1, 11)]
print(numbers)  # [1, 4, 9, 16, 25, 36, 49, 64, 81, 100]
for val in numbers[:4]:
    print(val, end=' ')  # 1 4 9 16

numbers = [value ** 2 for value in range(1, 6)]
myNumbers = numbers[:]
numbers.append(36)
myNumbers.append(49)
print(numbers)  # [1, 4, 9, 16, 25, 36]
print(myNumbers)  # [1, 4, 9, 16, 25, 49]

numbers = tuple(value ** 2 for value in range(1, 6))
print(numbers)  # (1, 4, 9, 16, 25)
numbers = tuple(value ** 2 for value in range(1, 4))
print(numbers)  # (1, 4, 9)

alien = {'color': 'green', 'points': 5}
# 访问字典键-值对
print(alien['color'], end=' ')
print(alien['points'])
# 添加键-值对
alien['x_position'] = 0
alien['y_position'] = 25
print(alien)  # {'color': 'green', 'points': 5, 'x_position': 0, 'y_position': 25}
# 删除键-值对
del alien['points']
print(alien)  # {'color': 'green', 'x_position': 0, 'y_position': 25}

alien = {'x_position': 0, 'y_position': 25}
for key, value in alien.items():
    print(f'Key = {key}, Value = {value}')
# 输出：
# Key = x_position, Value = 0
# Key = y_position, Value = 25

alien = {'x_position': 0, 'y_position': 25}
names = list(alien.keys())
print(names)  # ['x_position', 'y_position']

alien = {'x_position': 0, 'y_position': 25, 'a': 'test1', 'b': 'test2'}
for key in sorted(alien.keys()):
    print(key, end=' ')

alien = {'x_position': 0, 'y_position': 25, 'a': 'test1', 'b': 'test2'}
for value in alien.values():
    print(value)

alien = {'x_position': 0, 'y_position': 25}
aliens = []
for index in range(30):
    aliens.append(alien)
for app in aliens[:5]:
    print(app)

favoriteLan = {
    'jen': ['python', 'rust'],
    'sarah': ['c'],
    'edward': ['ruby', 'go'],
    'phil': ['shell', 'php'],
}

for name, languages in favoriteLan.items():
    print("\n" + name.title() + "'s favorite languages are: ")
    for language in languages:
        print("\t" + language.title())

users = {
    'torvalds': {
        'first': 'linus',
        'last': 'torvalds',
        'location': 'finland'
    },
    'buterin': {
        'first': 'vitalik',
        'last': 'buterin',
        'location': 'russia'
    }
}

for name, user in users.items():
    print(f"\nUsername: {name.title()}")
    print(f"first: {user['first'].title()}, last: {user['last'].title()}, location: {user['location'].title()}")

Username: Torvalds
first: Linus, last: Torvalds, location: Finland

Username: Buterin
first: Vitalik, last: Buterin, location: Russia

def greet_user(username):
    """greet example"""
    print(f"Hello, {username.title()}")


greet_user('siya')
print(greet_user.__doc__)

def describe_pet(animal_type, pet_name):
    print(f"I have a {animal_type}.")
    print(f"My {animal_type}'s name is {pet_name.title()}.")


describe_pet('hamster', 'harry')

describe_pet(animal_type='hamster', pet_name='harry')
describe_pet(pet_name='harry', animal_type='hamster')

def describe_pet(animal_type, pet_name='harry'):
    print(f"I have a {animal_type}.")
    print(f"My {animal_type}'s name is {pet_name.title()}.")


describe_pet('hamster', 'vitalik')
describe_pet('dog')

def get_formatted_name(first_name, last_name):
    full_name = first_name + ' ' + last_name
    return full_name.title()


full_name = get_formatted_name('vitalik', 'buterin')
print(full_name)  # Vitalik Buterin

def aTob(nums1, nums2):
    while nums1:
        nums2.append(nums1.pop())


nums1 = [val * 2 for val in range(1, 10)]
nums2 = []
aTob(nums1[:], nums2)

def aTob(*nums):
    print(nums)
aTob(1, 2, 4)  # (1, 2, 4)

def aTob(nums1, *nums2):
    print(nums1)
    print(nums2)
aTob(1, 2, 4)
# 1
# (2, 4)

def aTob(first, last, **nums):
    print(f"{first.title()} {last.title()}.")
    print(nums)
aTob('vitalik', 'buterin', age=31, sex='male')
# Vitalik Buterin.
# {'age': 31, 'sex': 'male'}

class Dog():
    def __init__(self, name, age):
        self.name = name
        self.age = age

    def sit(self):
        print(f"{self.name.title()} is now sitting.")

    def roll_over(self):
        print(f"{self.name.title()} rolled over.")


dog = Dog('vitalik', 20)
dog.sit()
dog.roll_over()

class Car:
    def __init__(self, make, model, year):
        self.make = make
        self.model = model
        self.year = year
        self.odometer_reading = 0

    def get_descriptive_name(self):
        long_name = f"{self.year} {self.make} {self.model}"
        return long_name

    def read_odometer(self):
        print(f"This car has {self.odometer_reading} miles on it.")

    def update_odometer(self, mileage):
        if mileage >= self.odometer_reading:
            self.odometer_reading = mileage
        else:
            print("You can't roll back an odometer!")

    def increment_odometer(self, miles):
        self.odometer_reading += miles


class ElectricCar(Car):
    def __init__(self, make, model, year):
        super().__init__(make, model, year)
        self.battery_size = 70

    def describe_battery(self):
        print(f"This car has a {self.battery_size}-kWh battery")


car = ElectricCar('tesla', 'model s', 2016)
longName = car.get_descriptive_name()
print(longName)  # 2016 tesla model s
car.describe_battery()  # This car has a 70-kWh battery

class Car:
    def fill_gas_tank(self):
        pass
class ElectricCar(Car):
    def fill_gas_tank(self):
        print("This car doesn't need a gas tank!")
car = ElectricCar()
car.fill_gas_tank()

from collections import OrderedDict
favorite_languages = OrderedDict()
favorite_languages['jen'] = ['python', 'rust']
favorite_languages['sarah'] = ['c']
favorite_languages['edward'] = ['ruby', 'go']
favorite_languages['phil'] = ['shell', 'php']

for name, languages in favorite_languages.items():
    print(f"\n{name.title()}'s languages: ", end=' ')
    for language in languages:
        print(f"{language.title()}", end=' ')

# This is a sample Python script.
# Press Shift+F10 to execute it or replace it with your code.
# Press Double Shift to search everywhere for classes, files, tool windows, actions, and settings.
import tkinter

top = tkinter.Tk()
# 进入消息循环
top.mainloop()

from tkinter import *
def say_hi():
    print("hello ~ !")
root = Tk()
frame1 = Frame(root, bd=128, cursor="plus", bg="white")
frame2 = Frame(root, bd=128, cursor="circle", bg="pink")
root.title("tkinter frame")
label = Label(frame1, text="Label", bg="red")
label.pack(fill=X)
hi_there = Button(frame2, text="say hi~", command=say_hi)
hi_there.pack()
frame1.pack(padx=10, pady=10, side=RIGHT)
frame2.pack(padx=10, pady=10, side=RIGHT)
root.mainloop()

import tkinter

top = tkinter.Tk()
top.title("emergency system")

frame = tkinter.Frame(top, bd=256, bg="white")
l1 = tkinter.Label(frame, text="name")
w = tkinter.Entry(frame, bd=10, highlightcolor="red", fg="black")
l1.pack(side=tkinter.LEFT)
w.pack(side=tkinter.LEFT)
frame.pack(padx=10, pady=10)

top.mainloop()

from tkinter import *
import tkinter.messagebox as messagebox


class Application(Frame):
    def __init__(self, master=None):
        Frame.__init__(self, master, bd=128, bg="green")
        self.pack()
        self.createWidgets()

    def createWidgets(self):
        self.nameInput = Entry(self, bd=12, bg="white")
        self.nameInput.pack()
        self.quitButton = Button(self, text='Quit', command=self.quit)
        self.helloButton = Button(self, text='hello', command=self.hello)
        self.helloButton.pack(side=LEFT, padx=10, pady=10)
        self.quitButton.pack(side=LEFT, padx=10, pady=10)

    def hello(self):
        name = self.nameInput.get()
        messagebox.showinfo("Message", "Hello %s" % name)


app = Application()
app.master.title("Hello World!")
app.mainloop()