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Python is not well-known for performance, but mastering some skills can also maximize program performance and avoid unnecessary waste of resources.1. Using Local variablesTry to use local variables instead of global variables: Ease of maintenance, improved performance, and memory savings.Use local variables to replace variables in the module namespace, such as ls = Os.linesep. On the one hand, it can improve the performance of the program, local varia

I want to learn Python with my colleagues. I want to talk about small functions (2). I want to learn python. The title of the previous lecture and this lecture is "big topic and small functions". The so-called big topic is that if these functions are traced back, they will find things that sound higher. This kind of thinking definitely inherits the fine tradition

range(n, 5):... print eachNum...>>> countToFour1(2)Traceback (most recent call last): File " 11-2.Function. Create a function and return the sum and product of two numbers. [Note] the question is modified according to the English version. [Answer] The Code is as follows: def func(a, b): c = a * b d = a + b return c, da = raw_input("Please input the first number: ... ")# From www.cnb

The lowercase master that returns a string' Please Enter your name ' . Lower () ' Please enter your name ' Replace returns a string when a string match is replaced' This is a test '. Replace ('is','AAA')' THAAA AAA a test'spilt is used to split a string into a sequence, which is a join inverse method ( a very important string method )>>>'1+2+3'. Split ('+')['1','2','3']>>> >>>'/usr/bin/env'. Split ('/')["

function that executes the business. The adorner syntax allows us to provide other parameters, such as @decorator (a), when called. This provides greater flexibility for the authoring and use of adorners.#Adorner with ParametersImport TimedefLogger (flag=""): defShoe_time (f):defInner (*x,**y): Start=Time.time () F (*x,**y) End=time.time ()Print(end-start)ifFlag = ="true": With open ("Log Records","a", encoding="UTF8") as G:g.write ("The value is:%s time is:%s\n"% (f (*x), (end-start))) retu

Python Intensive Training Note (7)-use the deque queue and save the object as a file, The deque object in the collections module is a queue with the first-in-first-out principle for normal queues. We can use this object to save data. For example, the system starts to randomly roll a game with a guess number ~ Then, the keyboard starts to receive your input. The number system will tell you whether the input

I used Python to write a game. Getting started with pygame (7): Collision Detection and pythonpygame We have already completed most of the aircraft wars, but there is still no way to officially launch the game, because the bullets cannot be knocked out of the plane. Only after this is done can the game be basically formed. Today's content is very simple, that is, the collision detection, and control the dis

In this article, we'll look at the dictionaries in Python, and in this article I'll Python dictionaryModify the instructions and illustrate how to modify Python dictionaryValues within the. Don't say much nonsense, let's get into the article. First we need to know what a modified dictionary is. Modify Dictionary The way to add new content to a dictionary is to a

Python built-in functions (7) -- bytearray, pythonbytearray English document: Classbytearray([Source[,Encoding[,Errors]) Return a new array of bytes.bytearrayClass is a mutable sequence of integers in the range 0 bytesType has, see Bytes and Bytearray Operations. The optionalSourceParameter can be used to initialize the array in a few different ways: If it isString, You must also giveEncoding(And optional

(' Welecome to HOME page ')Index ()#wrapper ()#Home ()Add more adorners:#add more adornersImport TimeImportRandom#Decorative DevicedefTimmer (func):defwrapper (): Start_time=time.time () func () Stop_time=time.time ()Print('run time is%s'% (stop_time-start_time)) returnwrapperdefAuth (func):defdeco (): Name=input ('Name:') Password=input ('Password:') ifName = ='Egon' andPassword = ='123': Print('Login Successful') func ()#wrapper () Else: Print('Login Err')

Chapter 2 of Python natural language processing exercises 12 and Chapter 2 Problem description: CMU pronunciation dictionary contains multiple pronunciations of certain words. How many different words does it contain? What is the proportion of words with multiple pronunciations in this dictionary? Because nltk. corpus. cmudict. entries () cannot use the set ()

example width = input('Enter number here:')price_width = 10item_width = width - price_widthheader_format = '%-*s%*s'content_format = '%-*s%*.2f'print '='*widthprint header_format % (item_width,'Item',price_width,'Price')print '-'*widthprint content_format % (item_width,'Apples',price_width,0.4)print content_format % (item_width,'Pears',price_width,0.5)print content_format % (item_width,'Banana',price_width,8)print content_format % (item_width,'Tomato',price_width,6)print '='*width Outp

The path to learning in Python -2018/7/10 3. Feature Development 3.1 Login verificationlogin.html views.py From django.shortcuts import Render, Httpresponsefrom django.http import Jsonresponsefrom django.views.decorators.csrf Import csrf_exemptfrom django.contrib Import authfrom blog.utils.verify_code import * @csrf_exemptdef login (Request): if Request.method = = "GET": Return render (Request, "login

Problem: Use regular expressions to match text patterns to identify the longest possible match to find the shortest possible matchWorkaround: Add after the * operator in the matching pattern. ModifierImportRe#Sample TextText ='computer says "No." Phone says "Yes."'#(a) Regex that finds quoted Strings-longest matchStr_pat = Re.compile (r'\"(.*)\"')Print(Str_pat.findall (text))#(b) Regex that finds quoted Strings-shortest matchStr_pat = Re.compile (r'\"(.*?) \"')Print(Str_pat.findall (text))>>> ==

[Python development practice] Windows 7 + VirtualBox + Ubuntu environment configuration, virtualboxubuntu 1. VirtualBox Installation Refer to the general installation method. VirtualBox 4.3.14 for Windows hosts: http://download.virtualbox.org/virtualbox/4.3.14/VirtualBox-4.3.14-95030-Win.exe 2. Install Ubuntu server Ubuntu-14.04-server-amd64 (http://www.ubuntu.c

The "1" getattr () function is Pythonthe core function of introspection"2" Python'sIntrospection: Python can view functions or module information stored as objects in memory, as well as related operations. "3" Related functions: GetAttr (), SetAttr (), delattr (), hasattr () GetAttr related usages are described below: GetAttr is used to return an object property, or the method can be visually discerned by a

Model class Design User UserInfo Uname Upwd ... Isdelete Product Category TypeInfo Ttitle Isdelete Product Goodsinfo Gtitle Gtype Gprice Gdesc Isdelete Shopping Cart Cartinfo User Goods Count Order OrderInfo User Ototal State Order Details Orderdetailinfo Order Goods Count Price

▲ Custom Class Python has a number of special-purpose functions like __slots__ that can help us customize the class. Official Document Link: https://docs.python.org/3.4/reference/datamodel.html#special-method-names 1) __str__ and __repr__ The sample code is as follows: >>>classStudent (object): ...def __init__(self, name): ... self.name=name ...>>> stu1 = Student ('Jack')>>>STU1__main__. Student Object at 0x01740e70>>>>Print(STU1)__main__. Student Obj

Python basic tutorial notes-Project 2-good painting-Day1, python-day1 Today, let's start with Project 2: drawing a good image. The graphical generation package ReportLab is used in the project. Therefore, install the package easy_install reportlab first. As you can see from the boo