字典实例：建立学生学号成绩字典，做增删改查遍历操作。

d={'01':'80','02':'70','03':'76','04':'86','05':'82'}

print(d.keys())

print(d.values())

d['08']=98

d['03']=99

d.pop('02')

print(d.get('07'))

print(d)

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。

str=list('123112312')

tu=tuple('abcdrfghj')

s=set([5,4,3,1,6])

d=dict(zip(tu,str))

print(str)

print(tu)

print(s)

print(d)

for i in str:

print(i)

for j in tu:

print(j)

for h in s:

print(h)

for k in d:

print(k,d[k])

 

 

英文词频统计实例

待分析字符串

分解提取单词

大小写 txt.lower()

分隔符'.,:;?!-_’

单词列表

单词计数字典

 

new='''After the Winter - Lenka

When the rain is pourin' down

"And there are snowflakes on your cheeks"

When your heart is frozen over

And there is a sea lost sun in weeks

Just remember,

Just remember,

After the winter comes the spring

That is when the blue birds

Starts to sing

And you can always count on this

After the winter comes the spring

When the trees have lost the color

And the sky is full of fears

When you feel you are going under

And your eyes are full of tears

When the bells are all hiding

And you are hiding too

Oh, darling just remember

That everything will soon be new

After the winter comes the spring

That is when the blue birds

Start to use their wings

And you can always count on this

After the winter comes the spring

Just remember,

Just remember,

Just remember,

Just remember,

After the winter comes the spring.

That is when the blue birds.

Starts to sing.

And you can always count on this

After the winter comes the spring

After the winter comes the spring'''

new = new.lower()

for i in ',."':

    new = new.replace(i,' ')

new = new.split(' ')

words = set(new)

d = {}

for i in words:

    d[i] = new.count(i)

for i in d:

    print('{0:<15}{1}'.format(i,d[i]))