Python

python functions1. Function definitionFunctions are well-organized, reusable pieces of code that are used to implement a single, or associated function. Functions can improve the modularity of the application, and the reuse of the code. You already

Original source: http://vnpy.org/2015/03/05/20150305_Python%E9%87%8F%E5%8C%96%E4%BA%A4%E6%98%93%E5%B9%B3%E5%8F%B0%E5%BC%80 %e5%8f%91%e6%95%99%e7%a8%8b%e7%b3%bb%e5%88%971-%e7%b1%bbctp%e4%ba%a4%e6%98%93api%e7%9a%84%e5%b7%a5%e4%bd%9c%e5 %8e%9f%e7%90%86/

Iterator iterator rulesIterations: Repeat things many times, just like in a loop.Not only can you iterate through dictionaries and sequences, but you can also iterate over other objects: As long as the object implements the __iter__ method.The

OS ModuleProvides an interface to invoke the operating system 12345678910111213141516171819202122232425262728293031 import osprint(‘getcwd()‘,os.getcwd()) #获取当前工作目录，即当前python脚本工作的目录路径#os.chdir("dirname") 

1.math Introduction>>>import Math #导入math模块 >>>dir (math) #这句可查看所有函数名列表 >>>help (math) # View specific definitions and function prototypes2. Common functionsACOs (x) # Return the arc cosine (measured in radians) of X.asin (x) #

Parsing command-line options for Argparse modules simple to useutil.py#!/usr/bin/env python#Coding=utf-8ImportArgparseparser= Argparse. Argumentparser (prog="MyProgram", description="a test of Argparse") parser.add_argument (" -A",

First, the module:module, which implements a set of code for a function with a mound code.Like functional programming and process-oriented programming, functional programming accomplishes a function, and other code is used to invoke it, providing

Overview　　Iterators are a way to access the elements of a collection. The iterator object is accessed from the first element of the collection until all of the elements have been accessed and finished. Iterators can only move forward without backing

1. Counter (counter)Counter is a supplement to the dictionary type that is used to track the number of occurrences of a value.PS: With all the functions of the Dictionary + own functionWe select some of the relatively common methods for example:As

Preliminary impressions of the Python webdriver automated test The following example demonstrates starting Firefox, browsing google.com, searching for cheese, waiting for search results, and then printing out the title of the search results page

Image Thresholding Segmentation is a widely used segmentation technique, which uses the difference between the target region and its background in the image, and considers the image as a combination of two kinds of regions (target region and

The preparation of the shopping cart is simply too difficult for me to be a little white that is not very proficient in functions. Various pits, all kinds of helpless Ah! But finally it is written!Not much to say, directly on the code!#！

Python crawlers crawl all the articles of a specified blog, Since the previous Article Z Story: Using Django with GAE Python, after capturing the full text of pages of multiple websites in the background, the general progress is as follows:1. Added

Python crawler URLError Exception Handling, pythonurlerror In this section, we mainly talk about URLError and HTTPError, as well as some processing for them. 1. URLError First, explain the possible causes of URLError: No network connection, that

Python multi-thread, asynchronous + multi-process crawler implementation code, python multi-thread Install TornadoThe grequests library can be used directly, and the asynchronous client of tornado is used below. Tornado is used asynchronously, and a

Use scrapy for Logging, scrapylogging   # Coding: UTF-8 _ author _ = 'similarface' ######################### use of Logging ### ################## import logging ''' 1. logging. CRITICAL-for critical errors (highest severity) fatal error 2. logging.

Django installation and start, Django installation and start 1. Install django Download the latest website of djangoon http://www.djangoproject.com/download. When downloading, make sure that the django version matches the Python version installed on

Preliminary Analysis of the Structure in C language programming, analysis of the C language structure The C-language struct is one of the powerful functions of C and a favorable condition for C ++ language derivation. In fact, when the struct

Python2 encoding summary, python2 Encoding The following are several problems that python2 often encounters and their explanations.   #-*-Coding: UTF-8 -*- Python2 uses ASCII encoding by default, but many Chinese characters are used in the actual

1. Upload of files such as word Excel TXT Image in Python django framework,1. File Upload (input tag) (1) html code (form is submitted using the post method) 1 2 3 4 table 5 6 (2) Submit the jq form to the background 1 $ ("# submitForm ").