This article mainly introduces the python web page capture example (python crawler). For more information, see the following code:
#-*-Encoding: UTF-8 -*-'''Created on 2014-4-24
@ Author: Leon Wong'''
Import urllib2Import urllibImport reImport timeImport OSImport uuid
# Obtain the url of the second-level pageDef findUrl2 (html ):Re1 = r 'HTTP: // tuchong.com/mon
In this article, we will show a very small piece of code, which is very attractive to us because it uses a very elegant and direct method to solve a common problem. for example, we want to check whether a string ends with a specific string? ", We usually use:
If needle. endswith ('ly ') or needle. endswith ('Ed') or needle. endswith ('in') or needle. endswith ('ERS'): print ('Is valid') else: print ('invalid ')
Ugly, right? If we check whether
The idea and code example of using the iterator to print the spiral matrix in Python, And the python Matrix
Ideas
A spiral matrix refers to a spiral matrix with numbers increasing from the first line to the right and increasing downward,To the left, and to the up, so that the cycle.The spiral matrix is represented by a two-dimensional array. The coordinates (x, y
Python simple code implementation example code of Yang Hui triangle, python Yang Hui
The Yang Hui triangle, also known as the Jia Xian triangle and Pascal triangle, is a geometric arrangement of the binary coefficient in the triangle.
Think of each row as a list, write a generator, and continuously output the list of the next row
Achieve the following output resu
Learn python by example: capture the webpage body using python,
This method is based on the text density. The original idea was derived from Harbin Institute of Technology's general webpage Text Extraction Algorithm Based on the row block distribution function. This article makes some minor modifications based on this.
Conventions:
This article makes statistics
Description: Python's urllib2 fetch page (urlopen) is automatically redirected (301,302). However, sometimes we need to get status information for 302,301 pages. You must obtain debugging information prior to the turn.
The following code will be able to avoid 302 redirects to the new page
#!/usr/bin/python #-*-coding:utf-8-*-#encoding =utf-8 #Filename: states_code.py impor T Urllib2 class Redircthandler (urllib2. Httpredirecthandler): "" "
The Vim plug-in is a. Vim script file that defines functions, mappings, syntax rules, and commands that you can use to manipulate windows, buffers, and rows. A general plug-in contains the command definition and event hooks. When you write a vim plug-in using Python, the function is written using VIML, although VIML is quick to learn, Python is more flexible, for exampl
An example is provided to illustrate the object attributes and class methods in Python surface object programming.
Attributes of python objectsNext, let's take a look at an instance to learn about the differences between classes, public attributes, private attributes, local variables, and global variables in python.
ro
This example describes the Python multi-process mechanism. Share to everyone for your reference. as follows:
In the past has only been exposed to Python multithreading mechanism, today searched a lot of progress, the relevant article seems not particularly much. After reading a few, a small try. Program as follows, the main content is to read a local file throug
Python file read/write and Exception Code example,
I. Reading data from a file
#!/usr/bin/env pythonwith open('pi') as file_object: contents = file_object.read() print(contents) ===================================3.1415926 5212533 2324255
1. Read data row by row
#!/usr/bin/env pythonfilename = 'pi'with open(filename) as file_object: for line in file_object: print(line) ================================
This article mainly introduces how to use the Python Django framework using an example of a voting program. Django is the most popular MVC Framework in the Python world. For more information, see
(1) about Django
Django is a framework constructed based on MVC. However, in Django, the Framework processes the part that the controller accepts user input. Therefore,
How to get started with Python? Create a website as an example.
The first important question is why we need to learn python? This question will guide you how to learn Python and how to learn it.
Take the website you finally want to create as an example. Starting from a gener
execution time.
If an exception occurs when a try statement executes, Python jumps back to the try and executes the first except clause that matches the exception, and the control flow passes through the entire try statement (unless a new exception is thrown when the exception is handled).If an exception occurs in the statement after the try, but there is no matching except clause, the exception is submitted to the upper try, or to the top of the p
Ansible is a pythonpackage and is a complete unpackandplay software. The only requirement on the client is that ssh has python and python is installed with the python-simplejson package, which is easy to deploy to the terminal. This article will introduce ansible as a method example for
Reference below: http://www.jb51.net/article/57183.htmIndividual is also a little tidy up, modify some of these errors, these errors related to Scrapy version selection, personal use of Python2.7 + scrapy1.1Another example of the URL (http://www.dmoz.org/Computers/Programming/Languages/Python/Books/) is often inaccessible, people notice, do not think that the script has a problem.Nonsense said, the followin
In this textbook, we assume that you have installed the scrapy. If you are not installed, you can refer to this installation guide.
We will use the Open Directory Project (DMOZ) As our example to crawl.
This textbook will take you through the following areas:
Create a new Scrapy project
Define the item that you will extract
Write a spider to crawl the site and extract items.
Write an item pipeline to store the proposed items
Scr
successful.Configuring the Pydev pluginSelect Preference in the Window menu,1, windows->preferences->pydev->interpreter-python,new a Python interpreter, fill in the Interpreter name and path, the path to select the corresponding Python.exe.Python 3.x is required in the following steps, Python 2 is optional. The individual is more accustomed to Unicode, so it is
As a concept, regular expressions are not unique to Python. However, the regular expressions in Python still have some small differences in the actual usage.
This article is part of a series about Python regular expression articles. In the first article in this series, we'll focus on how to use regular expressions in Python
, and then copy this folder to our test Python sibling folder, with a relative path specified, of course you can also do not copy, Then navigate to the Lib folder with the absolute pathThe code looks like this:Import syssys.path.append (". \lib") from Import Fileoperator def mytestreadinfo (): = Foperator.readinfofromfile ("D:\Code\PyTest\Test.txt") return= Fileoperator ()So we can use the 6th step in the VB code to call to succeed.Note: Whe
Related Articles:You can also find information about network resources in the following articles.Example in Python: A Basic verification tutorial
Urllib2 is a python component used to obtain URLs (Uniform Resource Locators. He provides a very simple interface in the form of urlopen functions,This is the ability to obtain URLs using different protocols. It also provides a complex interface to handle general
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