1. Introduction: A ubiquitous “magic phrase” In the process of learning Python, whether reading other people’s code or writing your own scripts, you will almost always encounter the following seemingly “mysterious” code: This code snippet, especially if __name__ == ‘__main__’ the conditional statement, represents a crucial and fundamental concept in Python programming. For beginners, it might seem … Read more
When browsing the web, you may have encountered situations where clicking a link automatically redirects the page to another address. Or, to be more technical, as a website developer, you might need to upgrade your website’s domain http:// or https://redirect older pages to newer URLs. Behind these scenarios, an important HTTP status code is at play— 301 . What is … Read more
Overview JSON (JavaScript Object Notation) is a lightweight data-interchange format that is easy for humans to read and write, and also easy for machines to parse and generate. PHP, as a popular server-side scripting language, supports reading and writing JSON data. Introduction to JSON JSON structure There are two main types of JSON data structures: … Read more
Getting Started with Django and Basic Configuration Django is a powerful and efficient Python web framework that follows the “Don’t Repeat Yourself” (DRY) principle, enabling developers to quickly build high-quality web applications. Today, we’ll explore Django’s basic configuration and core concepts! Django installation and project creation First, make sure you have a Python environment installed, … Read more
Introduction CSS (Cascading Style Sheets) is an essential tool in web design for controlling the style of web page elements. Among its components, float properties play a crucial role in layout design. This article will provide a detailed analysis of CSS float properties, including their principles, application scenarios, considerations, and how to implement floating layouts. I. Introduction to the … Read more
Introduction The Character class in Java is used to process single characters. It provides many static and instance methods to handle various character attributes, such as case conversion, comparison, and classification. Understanding the usage of the Character class is crucial when writing programs involving character processing. This article will provide a detailed analysis of the … Read more
1. Repository Initialization and Configuration 2. Remote warehouse operations # Add a remote repository: `git remote add origin <remote repository URL> ` # View remote repositories: `git remote -v` # Modify the remote repository URL: `git remote set-url origin <new remote repository URL> ` # Delete a remote repository: `git remote remove origin` 3. Branch … Read more
Detailed Explanation of Callback Functions in Machine Learning In Python programming, especially in the fields of deep learning and reinforcement learning, `BaseCallback` is typically a base class used to define the interface for callback functions. A callback function is a function that is called during training to perform specific tasks, such as logging, saving the … Read more
Detailed Explanation of ref and reactive in Vue 3 Differences and use cases of ref and reactive in Vue 3 ref ` reactive` and ` reactive reactive` are two core reactive functions in Vue 3’s Composite API, and they have different use cases. Core differences characteristic ref reactive Data types Any type (primitive types, objects, arrays) Object types … Read more
I. Insufficient Memory: Redis’s “Capacity Ceiling” Problem Redis, as an in-memory database, stores all data in memory. Once memory is full, it either triggers data eviction leading to the loss of frequently accessed data, or directly causes an OutOfMemoryError (OOM) that crashes the service. I have seen incidents during major e-commerce promotions where the database … Read more