一鼓作气 博客--第二篇 note2

1、循环正常结束是指没有中间截断，即没有执行break;

for i in range(10)

print(i)

else:

print("循环正常结束")

2、嵌套循环

for i in range(10)

for j in range(10)

print(i,j)

3.break 只会跳出当前循环

for i in range(10)

for j in range(10)

print(i,j)

if j >5:

break

4.for 循环，小循环不走

for i in range(10)

for j in range(10)

print(i,j)

if j >5:

break

print(i,j)

5.continue 跳出当次循环，继续下一次循环

for i in range(10)

for j in range(10)

print(i,j)

if j < 5:

continue

print(i,j)

6.break 跳出当前层循环，只跳一层；，continue跳出当次循环

for i in range(10)

for j in range(10)

print(i,j)

if j < 5:

continue

print(i,j)

7.数据类型

林海峰 blog：http://www.cnblogs.com/linhaifeng

变量：用来记录状态

变量值的变化即状态的变化，程序运行的本质就是来处理一系列状态的变化

数据类型存在的原因：利用不同类型的数据来表示数据变化

8.海峰的博客之 数据类型

http://www.cnblogs.com/linhaifeng/articles/5935801.html

python2 对数据长度有限制

python3 对数据长度没有限制

python3整形长度没有限制

9.布尔类型表示

bool(0)& bool(1)

10.浮点型

工资，有零钱有整钱

数据类型：

数字：整形，长整，布尔，浮点，复数

11.复数 x+yj

12.字符串

前面加r,打印引号之内所有内容

print("a\nsdf")

print(r"a\nsdf")

13.单引号套双引号

print("i'm laura")

14.首字母大写capitalize

msg = 'hello world'

print (msg.capitalize())

15.字符串居中显示 center

print (msg.center(30,"*"))

16.count

print (msg.count("l"))
17.位置[]

print (msg[3])
18.count

print (msg.count("l",4,10))

19.顾头不顾尾

打印从头开始，尾号-1的区间，不要尾号

20.endswith

print (msg.endswith("d"))
21.指定空格tab

msg1='a\tb'

print (msg1) #指定空格tab

22.tab长度指定

print (msg1.expandtabs(10))
23.一个tab建，是一个空格 pycharm 把tab建换成4个空格

24.msg.find('l'),找索引

print (msg.find('d'))

25.索引对应字符串

print ('{0}{1}{0}'.format('name','age'))

26.不写索引的数字，但必须全部一一对应

print ('{name}'.format(name = 'alex'))

28.index

msg2='a1234'

print(msg.index('e'))

29.isalnum

print(msg2.isalnum())

30.isalnum

msg3='123aA'

print(msg3.isalnum())

31.isalnum()

msg4='123a_A'

print (msg4.isalnum())

32.isalpha()

msg4='123a_A'

print(msg4.isalpha())

33.isdecimal() 十进制是否

msg5='10'

print (msg5.isdecimal())

34.isdigital isnumeric

msg6='10.2'

print(msg6.isnumeric())

35.isidentifier 单词是否包含关键字

msg7='if'

print(msg7.isidentifier())

36.islower(0

msg7='if'

print(msg7.islower())

37.isspace() 是否空格

msg8='f\n'

msg9='\t'

print(msg8.isspace())

print(msg9.isspace())

38.istital () 单词首字母都是大写

 msg10='Haibao'

print(msg10.istitle())

39.isupper()

 msg10='Haibao'

print(msg10.isupper())

40.ljust 左对齐

msg10='Haibao'

print(msg10.ljust(10,'*'))

41..rjust()右对齐

msg10='Haibao'

print(msg10.rjust(10,'*'))

42..center()居中

msg10='Haibao'

print(msg10.center(10,'*'))

43.lower 转换成小写

msg10='Haibao'

print (msg10.lower())

44.upper()全转换成大写

msg10='Haibao'

print (msg10.upper()) 

45.find index 区别

msg14='hello'

print(msg14.find('w'))   -->-1

print(msg14.index('o'))   -->4

46. strip去掉空格

msg11=' woaini '

print (msg11.strip())

47.strip()去掉右边空格

 msg11=' woaini '

print (msg11.rstrip())

48.strip()去掉左边空格

msg11=' woaini '

print (msg11.lstrip())

49.maketrans

msg12='my name is laura'

table=str.maketrans('laura','haiba')

table1=str.maketrans('l','k')
  print(msg12.translate(table))

print(msg12.translate(table1))

50.maketrans 部分

msg13='my name is laura'

table=str.maketrans('m','q')

51.zfill 右对齐，不够用0填充

msg13=' abc'

print(msg13.zfill(20))  #--->00000000000000000abc

print(msg13.ljust(20,'0'))  #--->abc00000000000000

52打印索引

msg13=' abceddd'

print(msg13[4])

53.打印切片 顾头不顾尾

msg13=' abceddd'
        print(msg13[0:5])

print(msg13[0:-1])

54.完全切分

print(msg13[:])

55.：冒号切分

print(msg13[:])

56.步长

msg13=' abceddd'

print(msg13[2:4:2]) #步长 是 2

57.len

msg13=' abceddd'

print(len(msg13))

58.round

msg13=' abceddd'

print(round(2.5))

print(round(2.6))

59.运算符

print(1+2)

print(1-2)

print(1*5)

print(3/2)

print(3**2)

60.地板除

print(3.4//2) #地板除

61.取余数

print(5%3)

62.比较 ==

print(3==2)

print(2==2)

****** 以上练习

msg = 'hello world'

print (msg.capitalize())

print (msg.center(30,"*"))

print (msg.count("l"))

print (msg[3])

print (msg.count("l",4,10))

print (msg.endswith("d"))

msg1='a\tb'

print (msg1) #指定空格tab

print (msg1.expandtabs(10))

print (msg.find('d'))

print ('{0}{1}{0}'.format('name','age'))

print ('{name}'.format(name = 'alex'))

print (msg.index('e'))

msg2= 'a124'

print (msg2.isalnum())

msg3='123aA'

print(msg3.isalnum())

msg4='123a_A'

print (msg4.isalnum())

print(msg4.isalpha())

msg5='10'

print (msg5.isdecimal())

msg6='10.2'

print(msg6.isnumeric())

msg7='if'

print(msg7.isidentifier())

print(msg7.islower())

msg8='f\n'

msg9='\t'

print(msg8.isspace())

print(msg9.isspace())

msg10='Haibao'

print(msg10.istitle())

print(msg10.isupper())

print(msg10.ljust(10,'*'))

print(msg10.rjust(10,'*'))

print(msg10.center(10,'*'))

print (msg10.lower())

print (msg10.upper())

msg11=' woaini '

print (msg11.strip())

print (msg11.rstrip())

print (msg11.lstrip())

msg12='my name is laura'

table=str.maketrans('laura','haiba')

table1=str.maketrans('l','k')

print(msg12.translate(table))

print(msg12.translate(table1))

msg13=' abc'

print(msg13.zfill(20))

print(msg13.ljust(20,'0'))

print(msg13[4])

print(msg13[0:5])

print(msg13[0:-1])

print(msg13[:])

print(msg13[2:4:2]) #步长 是 2

print(len(msg13))

print(round(2.5))

print(round(2.6))

print(1+2)

print(1-2)

print(1*5)

print(3/2)

print(3**2)

print(3.4//2) #地板除

print(5%3)

print(3==2)

print(2==2)

 ******

63.比较运算符号

print(3 > 2)

print(3 < 2)

print(3 >= 2)

print(3 <= 2) 
64.赋值运算

print(a+=10)   #a+=1  <== > a=a+1

65.age=age/3 与 age/=3一样

66.位运算 二进制按位置进行对比 异或运算

>>> 7&5

5

>>> bin(7)

'0b111'

>>> bin(5)

'0b101'

>>> 7|5

7

67.<< 左移动运算符

3<<2

12

68.~   按位取反运算

~6

-7

69.逻辑

a=1

a>1

False

70.and or

a=1

b=3

a>1  and  b<4

False

71.所有数字类型都自带布尔值 非0的数字的布尔值都是true,0=false

>>> bool(0)

False

>>>bool(5)

True 

72. 1自带布尔值true

if 1:

print('ok')

....

ok

73  if 0:

print('ok')

....

74.空格 true,空=false

msg='  '    <==> True

msg=''   <==> False

75.true and true

>>> 10 and 32

32

76.true and false

>>> 10 and 0

0

77成员运算 只能用于字符串

>>> msg = 'abce'

>>> '3'in msg

False

>>> 'a' in msg

True

78.缓存策略

>>> age=10

>>> id(age)

490865392

>>> age1=10

>>> id(age1)

490865392

>>> age1=10 -----> age1=age

79.太大了，就缓存

>>> age=10

>>> id(age)

490865392

>>> age1=10

>>> id(age1)

490865392

>>> age1=10 -----> age1=age

80.is内存 是否存入缓存 ，长的地址不一样，短的就一样,小数据缓存机制，大数据估计都要另辟内存。

>>> name='haibao'

>>> name1=name

>>> id(name)

18066096

>>> id(name1)

18066096

>>>

******

>>> age=111111111111

>>> age1=111111111111

>>> age is age1

False

>>> age3=10

>>> age4=10

>>> age3 is age4

True

>>>

81.死循环 while loop

count=0

while True:

print("i am laura")

count+=1

82. 打印占用时间

count=0

while True:

if count == 10000000

print("i am laura")

break

count+=1

83.while 加条件

count=0

while count < 1000:

print("i am laura")

break

count+=1

84.判断输入的不是数字，则继续

guess_age = input("age:")

if guess_age.isdigit():

guess_age = int(guess_age)

else:

continue

85.猜年龄 while 循环

count=0

oldboy_age = 56

while count < 3:

    guess_age =  input("age:")
    if guess_age.isdigit():
        guess_age = int(guess_age)
    else:
        continue
    if guess_age == oldboy_age:
        print('you are right')
        break
    elif guess_age > oldboy_age:
        print('guess smaller')
    else:
        print('guess a little bigger')
    count +=1

86. 取名字方法之 笨方法

>>> names = "luhaibao,luhailing,luhaiwen" 

>>> names 'luhaibao,luhailing,luhaiwen'

>>> names[9] 'l'

>>> names[9:19]

'luhailing,'

87.空列表 列表类型

>>> names = [] 

>>>type(names)

>>><class'list'> 

88.取names 第一个名字

>>>names = ['zhangsan', 'lisi', 'wangwu', 'zhaoliu', 'wuqi']

>>>names[1]
>>>'lisi'

89.切片取

>>>names = ['zhangsan', 'lisi', 'wangwu', 'zhaoliu', 'wuqi']

>>>names[1:3]

>>>'lisi', 'wangwu'

90.增加同时只能插入一个

names = ['zhangsan', 'lisi', 'wangwu', 'zhaoliu', 'wuqi']

names.append('laura')

print(names)

92.定位插入 同时只能插入一个

names = ['zhangsan', 'lisi', 'wangwu', 'zhaoliu', 'wuqi']

names.insert(2, 'loofoo')

print(names)

93.删除

names = ['zhangsan', 'lisi', 'wangwu', 'zhaoliu', 'wuqi']

names.remove('laura')

94.删除 三种方式

names = ['zhangsan', 'lisi', 'wangwu', 'zhaoliu', 'wuqi']

names.remove('laura')

del names[0]

print(names)

print(names.pop(2))

print(names)

95.改名字

names = ['zhangsan', 'lisi', 'wangwu', 'zhaoliu', 'wuqi']

names[2] = 'haibao'

96.查询

names = ['zhangsan', 'lisi', 'wangwu', 'zhaoliu', 'wuqi']

print(names[-3])

97.跳跃1一个

names = ['zhangsan', 'lisi', 'wangwu', 'zhaoliu', 'wuqi']

print(names[0::2])

********

98.最后3个

names = ['zhangsan', 'lisi', 'wangwu', 'zhaoliu', 'wuqi']

print(names[-3:])

99.取前三个

names = ['zhangsan', 'lisi', 'wangwu', 'zhaoliu', 'wuqi']

print(names[0:3])

100.取元素下标

names = ['zhangsan', 'lisi', 'wangwu', 'zhaoliu', 'wuqi']

print(names.index('zhaoliu'))

101.切片打印的位置是第二个位置

names = ['zhangsan', 'lisi', 'wangwu', 'zhaoliu', 'wuqi']

print(names.index('zhaoliu'))

first_index =  names.index('zhaoliu')

second_index = names.[first_index+1:].index('wuqi')

print('second',second_index)

102.查询其他的

names = ['zhangsan', 'lisi', 'wangwu', 'zhaoliu', 'wuqi']

print(names.index('zhaoliu'))

first_index =  names.index('zhaoliu')

second_index = names.[first_index+1:].index('wuqi')

print('second',second_index+first_index+1)

103.count

names = ['zhangsan', 'lisi', 'wangwu', 'zhaoliu', 'wuqi']

print('count',names.count('zhaoliu'))

104.清空列表

names = ['zhangsan', 'lisi', 'wangwu', 'zhaoliu', 'wuqi']

names.clear()

print(names)

105.extend 计算机认为字符串本身也是一个列表，所以也能合并,合并 extend namez 仍然存在

names = ['zhangsan', 'lisi', 'wangwu', 'zhaoliu', 'wuqi']
namez= ['zhenwwgsan', 'liwwi', 'wangwwwu', 'zhwwaoliu', 'wwwuqi']

names.extent(namez)

print(names)

106.reverse

names = ['zhangsan', 'lisi', 'wangwu', 'zhaoliu', 'wuqi']

print(names)

names.reverse()

print(names)

108.python3 字符串和数字无法排序

names = ['zhangsan',99,658, 'lisi', 'wangwu', 'zhaoliu', 'wuqi']

print(names)

names.sort()

print(names)

109.sort 按ascii 顺序编写

  names = ['zhangsan','99','658', 'lisi', 'wangwu', 'zhaoliu', 'wuqi']

print(names)

names.sort()

print(names)

110.copy

names = ['zhangsan','99','658', 'lisi', 'wangwu', 'zhaoliu', 'wuqi']

print(names)

namec=names.copy()

print(namec)  

111.两种方法区别

    names = ['zhangsan','99','658', 'lisi', 'wangwu', 'zhaoliu', 'wuqi']

print(names)

namec=names.copy()

namef=names

print(namec,id(names),id(namec))

print(namef,id(names),id(namef)) 

112 n4=names names变，n4也变，即相当于别名，软连接，用的是同一份数据。

      copy出来的数据，复制一份，保留了原来数据，被copy的数据有变化，新copy的数据没有变化

113.不能这样打下标

names = ['zhangsan','99','658', 'lisi', 'wangwu', 'zhaoliu', 'wuqi']

for i in names:

print(i,names.index(i))

114打印下标正确方法

names = ['zhangsan','99','658', 'lisi', 'wangwu', 'zhaoliu', 'wuqi']

for i in enumerate(names):

print(i)

115.打印下标正确方法

names = ['zhangsan','99','658', 'lisi', 'wangwu', 'zhaoliu', 'wuqi']

for i in enumerate(names):

print(i[0],i[1])

116.获取编号

names = ['zhangsan','99','658', 'lisi', 'wangwu', 'zhaoliu', 'wuqi']

for i ,ele in enumerate(names):

print(i,ele)

117.获取编号二

names = ['zhangsan', 'lisi', 'wangwu', 'zhaoliu', 'wuqi']

good = ['good','bad','just soso']

for i ,ele in enumerate(names):

print(i,ele,good[i])

output:

0 zhangsan good

1 lisi    bad

3 wangwu justsoso

118.嵌套列表 在a的【1】（即第二位）位置 写入一个列表

>>> a = ['haibao','hailing','haiwen']

>>> a

['haibao', 'hailing', 'haiwen']

>>> a[1]

'hailing'

>>> a[1]=['hailing','doctor','doctor']

>>> a

['haibao', ['hailing', 'doctor', 'doctor'], 'haiwen']

>>> a[1][1]

'doctor'

>>>

119.enumerate

products =[

    ['iphone4',4800],
    ['iphone5',5800],
    ['iphone6',6800],
    ['iphone7',7800],
]
for i, ele in enumerate(products):
    print(i,ele[0],ele[1])

output:

0 iphone4 4800 

1 iphone5 5800

2 iphone6 6800

3 iphone7 7800

121.三级菜单

menu ={

 "北京市":{

  "东城区":["东华门街道","景山街道","交道口街道","安定门街道","北新桥街道","朝阳门街道","东四街道","建国门街道","东直门街道","前门街道","崇文门外街道","东花市街道","龙潭街道","体育馆路街道","天坛街道","永定门外街"],

  "西城区":["西长安街街道"," 新街口街道","月坛街道","展览路街道","德胜街道","金融街街道","什刹海街道","大栅栏街道","天桥街道","椿树街道","陶然亭街道","广内街道","牛街街道","白纸坊街道","广外街道"],

  "朝阳区":["建外街道","朝外街道","呼家楼街道","三里屯街道","左家庄街道","香河园街道","和平街街道","安贞街道","亚运村街道","小关街道","酒仙桥街道","麦子店街道","团结湖街道","六里屯街道"],

  "丰台区":["右安门街道","太平桥街道","西罗园街道","大红门街道","南苑街道","东高地街道","东铁匠营街道","卢沟桥街道","丰台街道","新村街道","长辛店街道","云岗街道","方庄地区","宛平城地区","马家堡街道","和义街道","卢沟桥地区","花乡地区","南苑地区","长辛店镇","王佐镇"],

  "通州区":["中仓街道","新华街道","北苑街道","玉桥街道","永顺街道","梨园街道","宋庄镇","张家湾镇","漷县镇","马驹桥镇","西集镇","台湖镇","永乐店镇","潞城镇","于家务回族乡"],

  "石景山区":["八宝山街道","老山街道","八角街道","古城街道","苹果园街道","金顶街街道","广宁街道","五里坨街道","鲁谷街道"],

  "海淀区":["万寿路街道","永定路街道","羊坊店街道","甘家口街道","八里庄街道","紫竹院街道","北下关街道","北太平庄街道","学院路街道","中关村街道","海淀街道","青龙桥街道","清华园街道","燕园街道","香山街道","清河街道","花园路街道","西三旗街道","马连洼街道","田村路街道","上地街道","万柳地区","东升地区","曙光街道","温泉镇","四季青镇","西北旺镇","苏家坨镇","上庄镇"],

  "房山区":["城关街道","新镇街道","向阳街道","东风街道","迎风街道","星城街道","良乡地区","周口店地区","琉璃河地区","拱辰街道","西潞街道","阎村镇","窦店镇","石楼镇","长阳镇","河北镇","长沟镇","大石窝镇","张坊镇","十渡镇","青龙湖镇","韩村河镇","霞云岭乡","南窖乡","佛子庄乡","大安山乡","史家营乡","蒲洼乡"],

  "门头沟区":["大峪街道","城子街道","东辛房街道","大台街道","王平街道","潭柘寺镇","永定镇","龙泉镇","军庄镇","雁翅镇","斋堂镇","清水镇","妙峰山镇"],

  "大兴区":["兴丰街道","林校路街道","清源街道","亦庄地区","黄村地区","旧宫地区","西红门镇","瀛海地区","观音寺街道","天宫院街道","青云店镇","采育镇","安定镇","礼贤镇","榆垡镇","庞各庄镇","北臧村镇","魏善庄镇","长子营镇"],

  "怀柔区":["怀柔地区","泉河街道","龙山街道","雁栖地区","庙城地区","北房镇","杨宋镇","桥梓镇","怀北镇","汤河口镇","渤海镇","九渡河镇","琉璃庙镇","宝山镇","长哨营满族乡","喇叭沟门满族乡"],

  "平谷区":["滨河街道","兴谷街道","渔阳地区","峪口镇","马坊地区","金海湖地区","东高村镇","山东庄镇","南独乐河镇","大华山镇","夏各庄镇","马昌营镇","王辛庄镇","大兴庄镇","刘家店镇","镇罗营镇","黄松峪乡","熊儿寨乡"],

  "密云区":["鼓楼街道","果园街道","檀营地区","密云镇","溪翁庄镇","西田各庄镇","十里堡镇","河南寨镇","巨各庄镇","穆家峪镇","太师屯镇","高岭镇","不老屯镇","冯家峪镇","古北口镇","大城子镇","东邵渠镇","北庄镇","新城子镇","石城镇"],

  "延庆区":["百泉街道","香水园街道","儒林街道","延庆镇","康庄镇","八达岭镇","永宁镇","旧县镇","张山营镇","四海镇","千家店镇","沈家营镇","大榆树镇","井庄镇","大庄科乡","刘斌堡乡","香营乡","珍珠泉乡"],

  "顺义区":["胜利街道","光明街道","仁和街道","后沙峪街道","天竺街道","杨镇街道","牛栏山街道","南法信街道","马坡街道","石园街道","空港街道","双丰街道","旺泉街道","高丽营镇","

 

作业

1.购物车

2.三级菜单