Python

One, yesterday's content explainedBuilt-in functions: Focus on a few:Max (*args,key=none)Min (*args,key=none)Zip (*args,key=none)Sorted (*args,key=none,reverse=false)Reversed () Flip returns an iteratorFilter (Key,*args)Map (Key,*args)anonymous

In Python, when the code is long, want to see the code execution result in the Pycharm-console console or Python's own idle shell window, print some characters and so on, there are no line breaks between many lines affecting the viewing effect, so

Benefits of Inheritance :1. Build the class in the system to avoid repetitive operation .2, the new class is often based on existing classes, so that you can improve the code reuse degree .Characteristics of inheritance :1, the construction of the

The following values, when used as Boolean expressions, are considered false:False None 0 "" () [] {}The----is the standard value false and none, all types of numbers 0 (including floating-point, long-integer, and other types), empty sequences

0. Import keyboard class keys () The keys () class in Selenium provides most of the keyboard manipulation methods, and the Send_keys () method is used to simulate keys on the keyboard.# 导入键盘类 Keys()from selenium.webdriver.common.keys import

the Zen of Python, by Tim Peters Beautiful is better than ugly.Explicit is better than implicit.Simple is better than complex.Complex is better than complicated.Flat is better than nested.Sparse is better than dense.readability counts.Special cases

There are no ternary expressions in other languages in Python, but there are similar implementationsSuch as:A = 1=2ifelse 4The code above is a small demo in Python that implements the three mesh operation, if a>b, K equals 3, otherwise k equals

file operation: Procedure for file operation Open the file, get the file handle and assign a value to a variable Manipulating a file with a handle Close File The existing files are as followsSomehow, it seems the love I knew

The last time we had a brief look at what a singleton pattern is, we continue to explore today.Last content point this Python design pattern singleton mode (i) Last time we were talking about the GOF design pattern, which means that a class has

Combination SearchThe following is to talk about the implementation of the template-based language, without using JS at all. When speaking a bit of confusion, the other with the effect of the implementation of the small knowledge point is also

One, subprocess module#Import OS#os.system (' tasklist ') #类似cmd输入系统命令" "The purpose of subprocess is to start a new process and communicate with it. Only one class is defined in the Subprocess module: Popen. You can use Popen to create processes

The process of learning to merge and sort is very painful. It is not commonly used, and it seems that the time complexity seems to be the lowest in several sorts, and less than the time complexity of the fast queue, but it does not perform the

1. Generator functionsThe difference between a generator function and a normal function is that1. Use yield instead of return in the generator function, and yield can be called multiple times2. When the function runs to yield, the yield current

In the process of processing text in Python, there is often a case of text character set conversion,And we want to use a method, do not care about the text of the original character set is what, directly to the desired character set on it.Method One:

There are two types of members of a classPublic members, accessible from anywhereThe first two characters of a private member are underlined only if the method is internal to the class and the private member is named.class Foo: def __init__(self,

In this paper, we use the crawler example to illustrate the comparison of the execution efficiency between multiple threads, multi-processes and co-threads.Suppose we want to download images online now, an easy way is to use Requests+beautifulsoup.

Based on this period of time, Guangzhou's oil price change is relatively large, so I myself view the price of the site also increased, but as aProgrammerIsn't that an insult?? Can use the code to achieve why use manpower??? So I made a simple Python

Take window as an example:After installing Python, open cmd, command line input: Pip install virtualenv, installation process seeEnter the directory where you want to install the virtual environment, command-line input: Virtualenv-p

I. What is JSON1. JSON is the abbreviation for JavaScript Object notation, which is a data interchange format2. Essence is a string, is the string representation of the JS object3. Similar to the dictionary in Python, but there are some grammatical

A lot of grammar is not clear, people and stupid, this life is impossible to memorize, can only record them on the internet, need to come over to check.6.151.enumerate ()Enter a list or tuple to return an iterator consisting of an ordinal and a