Python

The Python built-in function sorted can sort an iterative object, with CMP and key two parameters, which have a significant effect on the efficiency of the ordering.CMP is a callback function, the prototype is: CMP (x, y), which is similar to the

Personally feel that iterator and yield achieve the same function, but iterator need to implement in the class, yield is implemented in the real function, both will save the stateThe generator is also implemented by iterators#!/usr/bin/env

One, recursive function:The program should know that in a function can also call other functions, which is called the function, but there is a special case, inside a function of the function of the call, we become the function of the recursive

Sometimes you need to add a wait time to your script in order to keep the pace running stable. Add hibernation: The time package needs to be introduced, and a fixed wait is selected. Example: Import time .... time.sleep (2) Smart wait: By

IntroducedThis article describes how to read files in Python.Body1.f = open (Input_file) for line in F:do_stuff (line) F.close ()2.For line in open (' myfile ', ' R '). ReadLines (): do_something (line)ReadLines () reads the file at a time to read

A=file_obj.read () default Read allB=file_obj.read (15) Read-only 15 charactersHelp (File.read)EG2:File_obj=open (' Test.txt ', ' R ')Line1=file_obj.readline ()print ' line1: ', line1 #me: The comma for printing prints on the same lineLine2=file_obj.

Output of PythonWith print a string, you can output the specified text to the screen. Implemented in code as follows:1 Print " I love baby! " 2 I love baby! 3 Print ("Hello world! " )4Hello world! 5Python will output the string or number you entered

In general, you do not need to install Python yourself. Because Python is already installed by default in most Linux versions, such as Fedora,ubuntu, you can also customize the installation of Python as needed. Use the following code to compile the

1. Give yourself a strong goal (reptile) 2. Get an overview of how this goal is achieved 3. Installation Environment (2.7.6) 4. Learn Python basic concepts and grammar (3c College) 5. Find a similar demo of the target, run up and play 6. To run the

1.filter (function, sequence) returns a sequence (sequence) that includes all elements that return a value of true after all call function (item) in a given sequence ( If possible, the same type is returned). If the sequence (sequence) is a

For example, I have a python program called getpath.py, which is used to get the full path name of the file I selected.getpath.pyImport sysif __name__ = = ' __main__ ': If Len (sys.argv)! = 2: sys.exit (' argv error! ') # #sys. argv[1]

In the specification of the HTTP protocol, the HTTP request is divided into three parts: the status line, the request header, and the request body. When sending an HTTP request, you need to indicate the method sent in the request header, including

First want to try Python crawler function, so with Easy_install installed BeautifulSoup, below is I write demo code, can simply see#coding =utf-8import urllib2from beautifulsoup import beautifulsoup as Bsurl_addr = '

When we download a. py file, we often see the if __name__ = = ' __main__ ' at the bottom of the code: Now let's briefly introduce its roleFirst we need to know that the module is an object, and that all modules have a built-in property __name__. If

Reference: Https://docs.python.org/3.4/library/unittest.html#module-unittestA picture solves the problem:Covers 5 pieces of content: case, Suite, loader, runner, result1 Case:TestCase (test Case): The basic class for all test cases, give the name of

The first step is to download the Psutil installation packageWebsite: https://pypi.python.orgSecond Step decompressionTar-zxv-f psutil-2.0.0.tar.gz #我下载的是2. Version 0.0CD psutil-2.0.0 #进入的目录中去.Third Step Installation:Python setup.py #这个是安装的方法一.Make

Use the pool in python multi-process, and the python process pool Use a pool in multiple Python processes. Specify several processes to run each time in the pool. When one of the processes ends, a new process is added.   #! /Usr/bin/env python #

Share some common open-source packages for Python development, and share the python open-source Package After installing Python, I will first install some frequently-used packages. Make a note and record it for query: Web FrameWorks Tornado, access:

Function programming in python One feature of functional programming is to allow1. Pass the function itself as a parameter to another function!2. Return a function!Python mainly has the following functional programming

Python implementation obtains the week number of a month and the week number of python. After searching for half a day, I couldn't find it. How to obtain the date of a month in the datetime processing of Python is the week of this month. However,