Some uses of Python to share _python

1 The use of regular expressions.

Copy Code code as follows:

#正则表达式的模块
Import re
#正则表达式
Repattern = '. *[0-9]{4} '
Pattern = Re.compile (Repattern)
#匹配
If Pattern.match (line):
Return True
Else
Return False

2 Use global variables in the function.

Copy Code code as follows:

def func ():
Global num

3 The Python default print output wraps.
If you need to output without a newline, at the end of the comma can be added.

Copy Code code as follows:

print ' Hello world! ',

4) String segmentation.
Based on a string segmentation, use Split (), the default parameter is white space characters, including spaces, carriage returns, tabs, and so on:
Strlist = Strs.split ('_')
If you need to slice from multiple strings, you can use regular expressions:

Copy Code code as follows:

#根据空格和水平制表符切分
Strlist = Re.split ("[\t\s]", STRs)

5 to determine whether a string is a number.

Copy Code code as follows:

If Str.isdigit ():
Return True
Else
Return False

6 file reading and writing

Copy Code code as follows:

#读文件
Fin = File (' 1.txt ', ' R ')
#写文件
Fout = File (' 1_ans.txt ', ' W ')
While True:
line = Fin.readline ()
#文件结尾
If Len (line) ==0:
Break
Fout.write (line)
Fin.close ()
Fout.close ()

7) Use of the list

Copy Code code as follows:

Anslist = []
#增加列表里的值
Anslist.append (' Hello1 ')
Anslist.append (' Hello2 ')
#对列表进行排序
Anslist.sort ()
#遍历输出
For ans in anslist
Print ans