字符串操作、文件操作，英文词频统计预处理

作业的要求：https://edu.cnblogs.com/campus/gzcc/GZCC-16SE1/homework/2684

1.字符串操作：

• 解析身份证号：生日、性别、出生地等。
• 凯撒密码编码与解码
• 网址观察与批量生成

def encryption(str, n):
    cipher = []
    for i in range(len(str)):
        if str[i].islower():
            if ord(str[i]) < 123-n:
                c = chr(ord(str[i]) + n)
                cipher.append(c)
            else:
                c = chr(ord(str[i]) + n - 26)
                cipher.append(c)
        elif str[i].isupper():
            if ord(str[i]) < 91-n:
                c = chr(ord(str[i]) + n)
                cipher.append(c)
            else:
                c = chr(ord(str[i]) + n - 26)
                cipher.append(c)
        else:
            c = str[i]
            cipher.append(c)
    cipherstr = ('').join(cipher)
    return cipherstr

#获得用户输入的明文
plaintext = input("请输入你的明文：")
ciphertext = encryption(plaintext, 3)
print(ciphertext)

　　

id=input('输入身份证号：')
birthyear=id[6:10]
birthmonth=id[10:12]
birthday=id[12:14]
sex=id[16]
if int(sex)%2==0:
    sex='女'
else:
    sex='男'
    print('身份证号码：{}'.format(id))
    print('出生日期：{}年{}月{}日'.format(birthyear,birthmonth,birthday))
    print('性别：{}'.format(sex))

　　

import urllib.request

url="https://edu.cnblogs.com/campus/gzcc/GZCC-16SE1/homework/2639"
req=urllib.request.Request(url)
resp=urllib.request.urlopen(req)
data=resp.read().decode('utf-8')

print(data)

　　

2.英文词频统计预处理

• 下载一首英文的歌词或文章或小说。
• 将所有大写转换为小写
• 将所有其他做分隔符（,.？！）替换为空格
• 分隔出一个一个的单词
• 并统计单词出现的次数。

text='''
Say say say
I come from Myrtle one brung late night melee
Say say say
We hung all summer sprung mattress with bae bae
Say say say
Trippin off Dyke and my name strike with pay day
Say say say
Flippin blue lighting tighting strapped with AK
Say say say
OG one told me one show me one eight ways
How to segue
Pussy power probably in headache
I reminisce my life innocence
Or life innocent
Or life intimate with fame
Like when repent
Like when we make out
Like when we gon get it good game
She wanna hang with a Starboy
The sun and the moon and star boy
Astronomer anonymous
I line up grind up these nine of us
And 5 of us have probably fucked
She mollied up I tallied up all the parts boy
Twenty legs arms head head
Head Head more head head
Oh God bless the dead yeah
I livin life high off life
I wear my chokes off to bed
I the greatest nigga
why you so scared to say it
I wanna rock I wanna rock I wanna cop more land
I never stop
I wanna quick advance on a bill if it ain one
Break everything I a hustler came from
'''
text=text.lower()
text=text.split()
text= text.replace(",","").replace(".","").replace(":","").replace(";","").replace("?","")
print(text)
s1=text.count('i')
s2=text.count('say')
print('i出现的次数{},say出现的次数{}'.format(s1,s2))

　　

import os,sys
project_path=os.path.dirname(os.path.abspath(__file__))
file_path=project_path+r'	1.txt'
with open(file_path,'w',encoding='utf-8')as f:
    f.write('1')

　　

3.文件操作

• 同一目录、绝对路径、相对路径
• 凯撒密码：从文件读入密函，进行加密或解密，保存到文件。
• 词频统计：下载一首英文的歌词或文章或小说，保存为utf8文件。从文件读入文本进行处理。

import os,sys
f=open(r"C:\UsersAdministratorDesktop2.txt","r")
line=f.readline()
while line:
    print(line,end="")
    line=f.readline()
f.close()

　　

4.函数定义

·加密函数

def JIAMI(code):
      code1=''
      for i in code:
           i=i+chr(ord(i)+3)
      return i

　　

·解密函数

def JIEMI(code):
      code1=''
      for i in code:
          i=i+chr(ord(i)-3)
      return i

　　

·读文本函数

def read(text):
     file=open(text,'r',encoding='utf8')
     return file.read()