print("hello python interpreter")
message = "hello python world"
print(message)
message = "hello zx"
print(message)
print(message)
message = 'i told my friend,"python is my favorite language"'
print(message)
区分大小写
name = "ada lovelace"
print(name.title())
print(name.upper())
print(name.lower())
合并拼接字符串
first_name = 'ada'
last_name = 'lovelace'
full_name=first_name+' '+last_name
print(full_name)
print("hell, "+full_name.title()+'!')
空白泛指非打印字符，如空格、制表符和换行符
添加制表符
print("python")
print("\tpython")
添加换行符
print("languages:\npython\nC\nJavascript")
print("languages:\n\tpython\n\tC\n\tJavascript")
去掉空白字符
favorite_languages = ' python '
print(favorite_languages+'sss')
print(favorite_languages.rstrip()+'sss')
favorite_languages = favorite_languages.rstrip()
print(favorite_languages)
print(favorite_languages.lstrip())
print(favorite_languages.strip())
print(3+2)
乘方 **
print(3 ** 2)
使用函数str()避免类型错误
age=23
message = "happy"+str(age)+'birthday'
print(message)
bicycles = ['a', 'b', 'c']
print(bicycles[0])
访问最后一位元素
print(bicycles[-1])
修改元素
bicycles[0]='zx'
print(bicycles)
添加元素
bicycles.append('ducati')
print(bicycles)
插入元素
bicycles.insert(1, '888')
print(bicycles)
删除元素
del bicycles[1]
print(bicycles)
pop
motorcyes = ['honda', 'yayay', 'suzuki']
print(motorcyes)
popped_motorcyes = motorcyes.pop()
print(motorcyes)
print(popped_motorcyes)
remove
motorcyes.remove('honda')
print(motorcyes)
sort() 排序
carts = ['bmw', 'audi', 'toyota', 'subaru']
carts.sort()
print(carts)
倒序
carts.sort(reverse=True)
print(carts)
临时排序 sorted()
carts = ['bmw', 'audi', 'toyota', 'subaru']
print("here is the original list:")
print(carts)
print("\nhere is the sorted list:")
print(sorted(carts))
print("\nhere is the original list again:")
print(carts)
carts.reverse()
print(carts)
len
print(len(carts))
遍历
magicians = ['alice', 'david', 'carolina']
for magician in magicians:
print(magician)
print("ssss")
range()函数
for value in range(1, 5):
print(value)
使用range()创建数字列表
number = list(range(1, 6))
print(number)
range()函数指定步长
even_numbers = list(range(2, 11, 3))
print(even_numbers)
使用range()创建需要的数字集
squares = []
for value in range(1, 11):
square = value ** 2
squares.append(square)
print(squares)
对数字列表执行简单的统计计算
digits = [1, 2, 3, 4, 5, 6, 7, 8, 9, 0]
print(min(digits))
print(max(digits))
print(sum(digits))
列表解析
arr = [value ** 2 for value in range(1, 11)]
print('列表解析。。。')
print(arr)
切片
players = ['chlars', 'martina', 'michael', 'florence', 'eli']
print(players[0:3])
如果没有指定第一个索引，python将自动从列表头开始
print(players[:4])
如果没有指定结束索引，python将自动从列表结束
print(players[2:])
最后三个的话也可以
print(players[-3:])
遍历切片
for player in players[:3]:
print(player.title())
复制列表
my_foods = ['pizza', 'falafel', 'carrot cake']
firend_foods = my_foods[:]
print("my favorite foods are:")
print(my_foods)
print("\nmy friend's favorite foods are:")
print(firend_foods)
my_foods = ['pizza', 'falafel', 'carrot cake']
firend_foods = my_foods[:]
my_foods.append('cannoli')
firend_foods.append('ice cream')
print("my favorite foods are:")
print(my_foods)
print("\nmy friend's favorite foods are:")
print(firend_foods)
my_foods = ['pizza', 'falafel', 'carrot cake']
这样赋值 行不通
firend_foods = my_foods
my_foods.append('cannoli')
firend_foods.append('ice cream')
print("my favorite foods are:")
print(my_foods)
print("\nmy friend's favorite foods are:")
print(firend_foods)
元组
列表非常适合用于存储在程序运行期间可能变化的数据集。
列表是可以修改的，这对处理网站的用户列表或游戏中的角色列表至关重要。
然而，有时候你需要创建一系列不可修改的元素，元组可以满足这种需求。
Python将不能修改的值称为不可变的，而不可变的列表被称为元组。
dimensions = (200, 100)
print(dimensions[0], dimensions[1])
不可修改
dimensions[0] = 250
遍历元组中所有的值
for value in dimensions:
print(value)
修改元组变量
dimensions = (200,50)
print("original dimensions")
for value in dimensions:
print(value)
dimensions = (400,100)
print("\nmodified dimensions")
for value in dimensions:
print(value)
print("if 语句-------------------------")
if语句
cars = ['audi', 'bmw', 'subaru', 'toyota']
for car in cars:
if car == 'bmw':
print(car.upper())
else:
print(car.title())
检测是否相等 python中检测是否相等是检测大小写的
print('Audi'=='audi')
print('Audi'.lower()=='audi')
检测是否不相等
requested_topping = 'mushrooms'
if requested_topping != 'anchovies':
print("hello the anchovies")
使用and检查多个条件
age_0 = 22
age_1 = 18
print(age_0 >= 21 and age_1 >=21)
或者
print((age_0 >= 21) and (age_1 >=21))
使用or检查多个条件
print(age_0 >= 21 or age_1 <=21)
检查特定值是否包含在列表中
requested_toppings = ['a', 'b', 'c']
print('a' in requested_toppings)
检测特定值是否不包含在列表中
banned_users = ['andrew', 'carolina', 'david']
user = 'marie'
if user not in banned_users:
print("特定值不在列表中。。。")
字典
在Python中，字典是一系列键—值对。每个键都与一个值相关联，你可以使用键来访问与之相关联的值。
与键相关联的值可以是数字、字符串、列表乃至字典。事实上，可将任何Python对象用作字典中的值。
alien_0 = {'color':'green', 'poiner':5}
print(alien_0['color'])
print(alien_0['poiner'])
添加键值对
alien_0['x_position'] = 2
alien_0['y_position'] = 24
print(alien_0)
创建空字典
alien_0 = {}
删除键值对
del alien_0['color']
由类似对象组成字典
favorite_languages = {
'jen':'python',
'color':'green',
'age':'66'
}
遍历字典
for key, value in favorite_languages.items():
print("\nkey\t"+key)
print("\nvalue\t"+value)
for name in favorite_languages.keys():
print(name.title())
按顺序遍历
for name in sorted(favorite_languages.keys()):
print(name.title()+"thank you ")
遍历所有的值
for value in favorite_languages.values():
print(value)
踢出重复值
for value in set(favorite_languages.values()):
print(value)
message = input("tel me ....")
print(message)
name = input("please enter your name:")
print("hello"+message)
prompt = "if you tell us who you are,we can personalize the message you see"
prompt+="\nWhat is your first name?"
name = input(prompt)
print("\nHello, "+name+"!")
