python 编程从入门到实践一
"""
备注：
"""
#修改字符串的大小写
#首字母大写
\'\'\'
name = "ada lovelace"
print(name.title())
print(name.upper())
print(name.lower())
first_name = \'ada\'
last_name = \'lovelace\'
full_name = first_name +" " + last_name
print(full_name)
print("Hello," + full_name.title() + "!")
print("\tPython")
print("Languages:\nPython\nC\nJavaScript")
favorite_language = \'python \'
print(favorite_language)
print(favorite_language.rstrip())
>>> 3/2
1.5
>>> 3/2.0
1.5
>>> 3%2
1
>>> 3**2
9
>>> 2+3*4
14
>>> 0.1 + 0.1
0.2
>>> 3 + 1.2
4.2
>>> 0.2 + 0.1
0.30000000000000004
>>> 3*0.1
0.30000000000000004
>>> 2*0.1
0.2
>>> 2*0.2
0.4
age = 23
message = "Happy " + str(age) + "rd Birthday!"
print(message)
#使用pop方法删除元素 与del 区别，del删除后不使用元素，pop删除后仍使用删除的元素
motorcycles = [\'honda\',\'yamaha\',\'suzuki\']
print(motorcycles)
popped_motorcycle = motorcycles.pop()
print(motorcycles)
print(popped_motorcycle)
motorcycles = [\'honda\',\'yamaha\',\'suzuki\']
last_owned = motorcycles.pop()
print(\'The last motorcycle I owned was a \' + last_owned.title() + \'.\')
print(motorcycles.pop(0))
print(motorcycles)
#根据指定的值删除，如果有多个重复的只要删除第一个元素
motorcycles = [\'honda\',\'yamaha\',\'suzuki\']
print(motorcycles)
motorcycles.append("ducati")
print(motorcycles)
motorcycles.remove("yamaha")
print(motorcycles)
#组织列表，使用方法sort()对列表进行永久性排序
cars = [\'bmw\',\'audi\',\'toyota\',\'subaru\']
cars.sort()
print(cars)
cars = [\'bmw\',\'audi\',\'toyota\',\'subaru\']
cars.sort(reverse = True)
print(cars)
cars = [\'bmw\',\'audi\',\'toyota\',\'subaru\']
print(sorted(cars))
print(cars)
cars = [\'bmw\',\'audi\',\'toyota\',\'subaru\']
cars.reverse()
print(cars)
print(len(cars))
print(cars[-1])
#使用for循环遍历整个列表
magicians = [\'alice\',\'david\',\'carolina\']
for magician in magicians:
print(magician)
print("Thank you !")
for value in range(1,5):
print(value)
numbers = list(range(1,6))
print(numbers)
print(list(range(0,11,2)))
#squares = []
#for value in range(1,11):
# square = value**2
# squares.append(square)
#
#print(squares)
squares = []
for value in range(1,11):
squares.append(value**2)
print(squares)
#列表解析
squares = [value**2 for value in range(1,11)]
print(squares)
#切片，使用列表的一部分
players = [\'charles\',\'martina\',\'michael\',\'florence\',\'eli\']
#获取1-3的子列表
print(players[0:3])
#获取2-4的子列表
print(players[1:4])
#返回离列表结尾距离相应的元素
print(players[-3])
players = [\'charles\',\'martina\',\'michael\',\'florence\',\'eli\']
for player in players[:3]:
print(player.title())
#使用切片复制列表得到列表的另一个副本，修改一个列表并不影响另一个列表
#把一个列表赋值给另一个列表，两个列表指向同一个列表，修改原列表会影响副本
list_01 = [1,2,3]
list_02 = list_01[:]
print(list_01)
list_01.append(4)
print(list_01)
print(list_02)
list_03 = [4,5,6]
list_04 = list_03
list_03.remove(5)
print(list_04)
#元组不可修改，元组变量可以修改
t = (1,2,3)
print(t[0])
print(t[1])
t = [2,5]
print(t)
cars = [\'audi\',\'bmw\',\'subaru\',\'toyota\']
for car in cars:
if car == \'bmw\':
print(car.upper())
else:
print(car.title())
>>> car = \'Audi\'
>>> car
\'Audi\'
>>> car == \'audi\'
False
>>> car.lower() == \'audi\'
True
>>> car = \'Audi\'
>>> car
\'Audi\'
>>> car == \'audi\'
False
>>> car.lower() == \'audi\'
True
>>> 6 != 5
True
>>> age = 18
>>> age == 18
True
>>> age = 19
>>> age < 21
True
>>> age <= 21
True
>>> age >= 21
False
>>> age_0 = 22
>>> age_1 = 18
>>> age_0 >= 21 and age_1 >= 21
False
>>> age_1 =22
>>> age_0 >=21 and age_1>=21
True
>>> (age_0>=21) and (age_1>=21)
True
>>> age_0=22
>>> age_1=18
>>> age_0>=21 or age_1>=21
True
>>> age_0 = 18
>>> age_0 >= 21 or age_1 >= 21
False
# in not in 检查值是包含在列表中
>>> li = [1,2,3]
>>> 1 in li
True
>>> 2 in li
True
>>> 5 in li
Falise
>>> 1 not in li
Falise
>>> 5 not in li
True
#游乐场收费标准：4岁以下免费，4到18岁5元，18岁（含）以上10元
def show_fee(age):
if age < 4:
return "免费"
#elif age >= 4 and age < 18:
elif age < 18:
return "5元"
else:
return "10元"
if __name__ == "__main__":
print(show_fee(3))
print(show_fee(4))
print(show_fee(6))
print(show_fee(18))
age = 12
if age < 4:
price = 0
elif age < 18:
price = 5
else:
price = 10
print("your admission cost is ￥" + str(price) + ".")
#当知道输入条件可以不用else,避免引入未知危害条件
age = 65
if age < 4:
price = 0
elif age < 18:
price = 5
elif age >= 18:
price = 10
print("your admission cost is ￥" + str(price) + ".")
#如果只想执行一个代码块使用if-elif-else 如果要执行多个代码块就要运行一系统独立的if条件
li = [\'reganmian\',\'banhuanggua\',\'huashengmi\']
if \'reganmian\' in li:
print("add reganmian")
if \'banhuanggua\' in li:
print("add banhuanggua")
if \'nirou\' in li:
print(\'add niurou\')
#优化
li = [\'reganmian\',\'banhuanggua\',\'huashengmi\']
for i in li:
print("adding " + i + \'.\')
print("Done!")
li = [\'reganmian\',\'banhuanggua\',\'huashengmi\']
for i in li:
if i == \'huashengmi\':
print("sory,we are out of huashengmi ")
else:
print("adding " + i + \'.\')
print("Done!")
li = [\'reganmian\',\'banhuanggua\',\'huashengmi\']
for i in li:
if i == \'huashengmi\':
print("sory,we are out of huashengmi ")
else:
print("adding " + i + \'.\')
print("Done!")
#判断列表是否为空
li = []
li.append(1)
if li:
for i in li:
print(i)
else:
print("列表是空的")
#使用多个列表
li_0 = [1,2,3,4,5]
li_1 = [5,8,9]
for i in li_1:
if i in li_0:
print("adding " + str(i) + \'.\')
else:
print("sorry,we don\'t find " + str(i) + \'.\')
print("Done!")
#字典的创建 添加值
student = {\'name\':\'liming\',\'age\':22}
print(student[\'name\'])
print(student[\'age\'])
print(\'you are \' + str(student[\'age\']) + " years old")
student[\'address\']=\'江苏省\'
student[\'ID\']= \'0250001\'
print(student)
del student[\'address\']
print(student)
dt = {}
dt[\'color\'] = \'green\'
dt[\'point\'] = 5
print(dt)
dt[\'color\'] = \'yellow\'
print(dt)
favorite_languages = {
\'jen\': \'python\',
\'sarah\': \'c\',
\'edward\': \'ruby\',
\'phil\': \'python\',
}
print("Sarah\'s favorite language is " +
favorite_languages[\'sarah\'].title() +
\'.\')
for k,v in favorite_languages.items():
print("\nKey: " + k)
print("Value: " + v)
for name in favorite_languages:
print(name.title())
for name in favorite_languages.keys():
print(name.title())
if \'erin\' not in favorite_languages.keys():
print("Erin,please take our your poll!")
for name in sorted(favorite_languages.keys()):
print(name.title())
for language in favorite_languages.values():
print(language)
#遍历字典的值，去重打印
for language in set(favorite_languages.values()):
print(language)
#嵌套 字典列表
li_0 = {\'c\':\'green\',\'p\':5}
li_1 = {\'c\':\'yellow\',\'p\':10}
li_2 = {\'c\':\'red\',\'p\':15}
li = [li_0,li_1,li_2]
print(li)
for i in li:
print(i)
aliens = []
for alien_number in range(30):
new_a = {\'c\':\'green\',\'p\':5,\'speed\':\'slow\'}
aliens.append(new_a)
print(len(aliens))
for alien in aliens[:5]:
if alien[\'c\'] == \'green\':
alien[\'c\'] = \'yellow\'
alien[\'p\'] = 10
alien[\'speed\'] = \'medium\'
print(alien)
print("...")
pop_lang = {
\'a\':[\'python\',\'ruby\'],
\'b\':[\'c\'],
\'c\':[\'ruby\',\'go\'],
\'d\':[\'python\',\'java\']
}
print(pop_lang)
for i in pop_lang[\'a\']:
print(i)
for k,v in pop_lang.items():
print("%s=%s" %(k,v))
for name,languages in pop_lang.items():
print("\n" + name.title() + "\'s favorite languages are:")
for language in languages:
print("\t" + language.title())
#input 与 while
mesg = input("请输入你的姓名：")
print("Hello, " + mesg + "!")
prompt = "If you tell us who you are,we can personalize the messaages you see."
prompt += \'\nWhat is your first name?\'
name = input(prompt)
print("\nHello, " + name + "!")
#使用int来获取数值输入
age = input("How old are you? ")
print(age)
age = int(age)
if age >= 18:
print("you have vote")
num = input("请输入一个整数，我告诉你是奇数还是偶数：")
num = int(num)
if num%2 == 0:
print("您输入的数" + str(num) + "是偶数")
else:
print("您输入的数" + str(num) + "是奇数")
#while循环
i = 1
while i < 6:
print(i)
i +=1
mesg = "输入\'quit\'循环退出，否则循环一个运行"
m = ""
while m != \'quit\':
m = input(mesg)
print(m)
mesg = "输入\'quit\'循环退出，否则循环一个运行："
m = ""
while m != \'quit\':
m = input(mesg)
if m != \'quit\':
print(m)
mesg = "输入\'quit\'循环退出，否则循环一个运行："
flag = True
while flag:
m = input(mesg)
if m == \'quit\':
flag = False
else:
print(m)
mesg = "输入\'quit\'循环退出，否则循环一个运行："
while True:
m = input(mesg)
if m == \'quit\':
break
else:
print(m)
i = 0
while i < 10:
i += 1
if i % 2 == 0:
continue
print(i)
#for 循环遍历时不能修改修改，while可以
#在列表之间移动元素
unconfirmed = [\'alice\',\'brian\',\'candace\']
confirmed = []
while unconfirmed:
cur_user = unconfirmed.pop()
print("已验证用户：" + cur_user.title())
confirmed.append(cur_user)
#显示所有已验证用户
print("已经验证的用户：")
for c in confirmed:
print(c.title())
#删除包含特定值的元素
p = [\'a\',\'b\',\'c\',\'d\',\'a\']
print(p)
while \'a\' in p:
p.remove(\'a\')
print(p)
#使用用户输入来填充字典
questions = {}
flag = True
while flag:
name = input("\nwhat\'s your name? ")
question = input("Which mountain would you like? ")
questions[name] = question
repeat = input("还有人参加调查么?(yes/no) ")
if repeat == \'no\':
flag = False
print("\n调查结果：")
for name,question in questions.items():
print(name + " would like to climb " + question + \'.\')
\'\'\'
def greet_user():
print("Hello")
greet_user()