The operating environment of this tutorial: windows7 system, python3 version, DELL G3 computer
python uses class to define classes
class is a keyword that tells the system that we want to define a class. Add a space after class and then add the class name. Class name rules: the first letter is capitalized. If multiple words are named in camel case, such as: KingMao, the parentheses after the class name indicate that this class is based on a certain class definition and belongs to inheritance-related knowledge. For the time being, write object
class Dog(object): The code inside the class belongs to the description of the type, which is equivalent to describing the template. Functions defined within a class are generally called methods def eat(self, n): print('I ate %d apples' % n) def add_fn(self, a, b): return a b
Placing parentheses after the class name means creating an object (instance) of this type anb = Dog()print(anb, type(anb))anb.eat(4)a = anb. add_fn(3, 7)print(a)
xiaoquan = Dog()print(xiaoquan, type(xiaoquan))xiaoquan.eat(3)
anbei.name = 'anbei'print(anbei.name)
class Pig(object): a special function, when This method is automatically called when an object of this type is created. Usually this special method is called a constructor (initialization method): def __init__(self, name, age): self.name = name self.age = age def add_fn(self, a, b): return a b
The first parameter of the object method points to the object calling this method by default # Which object calls this method, self will point to this object # self is not a keyword and can be changed to Other variable names, but this is not recommended. def show(self): print(self.name, self.age)
The above is the detailed content of What does class mean in python?. For more information, please follow other related articles on the PHP Chinese website!

Hot AI Tools

Undress AI Tool
Undress images for free

Undresser.AI Undress
AI-powered app for creating realistic nude photos

AI Clothes Remover
Online AI tool for removing clothes from photos.

Clothoff.io
AI clothes remover

Video Face Swap
Swap faces in any video effortlessly with our completely free AI face swap tool!

Hot Article

Hot Tools

Notepad++7.3.1
Easy-to-use and free code editor

SublimeText3 Chinese version
Chinese version, very easy to use

Zend Studio 13.0.1
Powerful PHP integrated development environment

Dreamweaver CS6
Visual web development tools

SublimeText3 Mac version
God-level code editing software (SublimeText3)

To realize text error correction and syntax optimization with AI, you need to follow the following steps: 1. Select a suitable AI model or API, such as Baidu, Tencent API or open source NLP library; 2. Call the API through PHP's curl or Guzzle and process the return results; 3. Display error correction information in the application and allow users to choose whether to adopt it; 4. Use php-l and PHP_CodeSniffer for syntax detection and code optimization; 5. Continuously collect feedback and update the model or rules to improve the effect. When choosing AIAPI, focus on evaluating accuracy, response speed, price and support for PHP. Code optimization should follow PSR specifications, use cache reasonably, avoid circular queries, review code regularly, and use X

Use Seaborn's jointplot to quickly visualize the relationship and distribution between two variables; 2. The basic scatter plot is implemented by sns.jointplot(data=tips,x="total_bill",y="tip",kind="scatter"), the center is a scatter plot, and the histogram is displayed on the upper and lower and right sides; 3. Add regression lines and density information to a kind="reg", and combine marginal_kws to set the edge plot style; 4. When the data volume is large, it is recommended to use "hex"

String lists can be merged with join() method, such as ''.join(words) to get "HelloworldfromPython"; 2. Number lists must be converted to strings with map(str, numbers) or [str(x)forxinnumbers] before joining; 3. Any type list can be directly converted to strings with brackets and quotes, suitable for debugging; 4. Custom formats can be implemented by generator expressions combined with join(), such as '|'.join(f"[{item}]"foriteminitems) output"[a]|[

Install pyodbc: Use the pipinstallpyodbc command to install the library; 2. Connect SQLServer: Use the connection string containing DRIVER, SERVER, DATABASE, UID/PWD or Trusted_Connection through the pyodbc.connect() method, and support SQL authentication or Windows authentication respectively; 3. Check the installed driver: Run pyodbc.drivers() and filter the driver name containing 'SQLServer' to ensure that the correct driver name is used such as 'ODBCDriver17 for SQLServer'; 4. Key parameters of the connection string

pandas.melt() is used to convert wide format data into long format. The answer is to define new column names by specifying id_vars retain the identification column, value_vars select the column to be melted, var_name and value_name, 1.id_vars='Name' means that the Name column remains unchanged, 2.value_vars=['Math','English','Science'] specifies the column to be melted, 3.var_name='Subject' sets the new column name of the original column name, 4.value_name='Score' sets the new column name of the original value, and finally generates three columns including Name, Subject and Score.

Pythoncanbeoptimizedformemory-boundoperationsbyreducingoverheadthroughgenerators,efficientdatastructures,andmanagingobjectlifetimes.First,usegeneratorsinsteadofliststoprocesslargedatasetsoneitematatime,avoidingloadingeverythingintomemory.Second,choos

First, define a ContactForm form containing name, mailbox and message fields; 2. In the view, the form submission is processed by judging the POST request, and after verification is passed, cleaned_data is obtained and the response is returned, otherwise the empty form will be rendered; 3. In the template, use {{form.as_p}} to render the field and add {%csrf_token%} to prevent CSRF attacks; 4. Configure URL routing to point /contact/ to the contact_view view; use ModelForm to directly associate the model to achieve data storage. DjangoForms implements integrated processing of data verification, HTML rendering and error prompts, which is suitable for rapid development of safe form functions.

Introduction to Statistical Arbitrage Statistical Arbitrage is a trading method that captures price mismatch in the financial market based on mathematical models. Its core philosophy stems from mean regression, that is, asset prices may deviate from long-term trends in the short term, but will eventually return to their historical average. Traders use statistical methods to analyze the correlation between assets and look for portfolios that usually change synchronously. When the price relationship of these assets is abnormally deviated, arbitrage opportunities arise. In the cryptocurrency market, statistical arbitrage is particularly prevalent, mainly due to the inefficiency and drastic fluctuations of the market itself. Unlike traditional financial markets, cryptocurrencies operate around the clock and their prices are highly susceptible to breaking news, social media sentiment and technology upgrades. This constant price fluctuation frequently creates pricing bias and provides arbitrageurs with
