Python usage-Python tutorial

I learned some python recently. I had to process a file yesterday, so I tried it. 1) use of regular expressions.

The code is as follows:

# Regular expression module
Import re
# Regular expression
RePattern = '. * [0-9] {4 }'
Pattern = re. compile (rePattern)
# Matching
If pattern. match (line ):
Return True
Else:
Return False

2) use global variables in functions.

The code is as follows:

Def func ():
Global num

3) by default, python outputs a line feed in print.
If you do not need to output a line break, add a comma at the end.

The code is as follows:

Print 'Hello World! ',

4) string splitting.
Use split () to split a string. the default parameter is blank, including spaces, carriage returns, and tabs:
StrList = strs. split ('_')
To split strings, use the regular expression:

The code is as follows:

# Split based on spaces and horizontal tabs
StrList = re. split ("[\ t \ s]", strs)

5) determine whether a string is a number.

The code is as follows:

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

6) file read/write

The code is as follows:

# Reading files
Fin = file('1.txt ', 'r ')
# Writing files
Fout = file('audio ans.txt ', 'w ')
While True:
Line = fin. readline ()
# End of a file
If len (line) = 0:
Break
Fout. write (line)
Fin. close ()
Fout. close ()

7) Use of the list

The code is as follows:

AnsList = []
# Adding values in the list
AnsList. append ('hello1 ')
AnsList. append ('hello2 ')
# Sort the list
AnsList. sort ()
# Traverse output
For ans in ansList
Print ans