组合数据类型练习，英文词频统计实例上

字典实例：建立学生学号成绩字典，做增删改查遍历操作。
列表，元组，字典，集合的遍历。
总结列表，元组，字典，集合的联系与区别。
英文词频统计实例
1. 待分析字符串
2. 分解提取单词
  1. 大小写 txt.lower()
  2. 分隔符'.,:;?!-_’
  3. 单词列表
3. 单词计数字典

# 实例：建立学生学号成绩字典，做增删改查遍历操作。

 1 student_name = ['小叶','小在','小林','小红','小明','小东','小花']
 2 student_g = [100,99,98,97,96,95,94]
 3 d = dict(zip(student_name,student_g))
 4 # d = {'小叶':100,'小林':99}
 5 # 增加
 6 d['小紫'] = 93
 7 # 删除
 8 d.pop('小花')
 9 # 修改
10 d['小东'] = 60
11 # 查询
12 d.get('小叶','空')



# 列表、元组、字典、集合的遍历

l = list('23132111123132')
t = tuple('1233211232123')
s = set(l)
d = dict(zip([1,2,3,4],[4,3,2,1]))
for i in l:
    print(i)
for i in t:
    print(i)
for i in s:
    print(i)
for i in d:
    print(i)


# 总结列表、元组、字典、集合的联系与区别
# （1）列表是任意对象的序列。列表用方括号表示。
# （2）将一组值打包到一个对象中，称为元组。元组用圆括号表示。元组和列表的大部分操作相同。但是，列表是不固定的，可以随时插入，删除；而元组一旦确认就不能够再更改。所以，系统为了列表的灵活性，就需要牺牲掉一些内存；而元组就更为紧凑。
# （3）与列表和元组不同，集合是无序的，也不能通过索引进行访问。此外，集合中的元素不能重复。
# （4）字典就是一个关联数组或散列表，其中包含通过关键字索引的对象。用大括号表示。与集合相比，通过关键字索引，所以比集合访问方便。字典是Python解释器中最完善的数据类型。


# 实例：词频统计

 1 str = '''
 2 When you wake up in the morning
 3 When you haven't started to think
 4 There is a whole brand new day
 5 Open wide and waiting for you
 6 I know in life's sorrow
 7 you're on the verge of drowning
 8 May your tears flee with yesterday
 9 blow away with the wind
10 When you wake up in the morning
11 When you haven't started to think
12 The world is out there calling
13 open eyes to new beginning
14 A newborn sun is shinning
15 Chasing shadows from your mind
16 Everything will be alive,
17 under the sunshine's smile
18 Come out from your corner
19 No doubt in join us
20 You can decide the future
21 Devote your youthful power to this world
22 Come together, hand in hand together
23 I know you'll do
24 We pray and believe
25 that tomorrow will be better.
26 No, I don't know what your name is
27 But you're so familiar to me
28 Cause we belong to one family
29 You can hear my heart calling
30 Life can be music,
31 rainbows can be reached
32 If you face yourself truly
33 keep striving for your dream
34 Come out from your corner
35 No doubt in join us
36 You can decide the future
37 Devote your youthful power to this world
38 Come together, hand in hand together
39 I know you'll do
40 We pray and believe
41 that tomorrow will be better.
42 When you wake up in the morning
43 When you haven't started to think
44 There is a whole brand new day
45 Open wide and waiting for you
46 I know in life's sorrow
47 you're on the verge of drowning
48 May your tears flee with yesterday
49 Blow away with the wind
50 Come out from your corner
51 No doubt in join us
52 You can decide the future
53 Devote your youthful power to this world
54 Come together, hand in hand together
55 I know you'll do
56 We pray and believe
57 that tomorrow will be better.
58 '''
59 # 将，？.！变成空格
60 str = str.replace(',',' ')
61 str = str.replace('
','')
62 str = str.replace('  ','')
63 # 将所有大写转换为小写
64 str = str.lower()
65 # 把歌词切片
66 words = str.split(' ')
67 # 定义一个空字典
68 di = {}
69 # 单词排序
70 words.sort()
71 # 用循环，写入字典
72 disc = set(words)
73 for i in disc:
74     di[i] = 0
75 for i in words:
76     di[i] = di[i]+1
77 items = di.items()
78 
79 print(items)