This tutorial shows how to install the Python myqr package and use it from the command line to generate ordinary, artistic, and animated QR codes, covering size, naming, output directory, image overlay, color, contrast, and brightness options with clear examples.
Learn how to configure Xshell for remote server access, create and manage sessions, and use the Compose feature to execute commands across multiple terminals simultaneously, complete with detailed step-by-step instructions and visual screenshots.
This tutorial walks you through using Python and Pandas to import Excel files, explore DataFrames, apply filters, perform statistical calculations, create pivot tables, and emulate Excel functions like VLOOKUP, providing code examples and visual guides for each step.
This guide explains how to quickly deploy a JD Chain blockchain environment by downloading the peer and gateway packages, configuring ports, initializing nodes, creating keys and ledgers, and launching management tools, providing step‑by‑step commands and screenshots for a complete setup.
Learn how to create a simple stack‑based virtual machine in Python, covering its core components—code, stack, and address—along with essential methods like push, pop, dispatch, and run, plus an interactive REPL, complete with example code and execution output.
This article provides a detailed, illustrated walkthrough for installing Xshell on Windows, covering common error causes, downloading the official version, and each step of the setup wizard from launching the installer to completing the configuration.
This comprehensive tutorial by data‑science instructor Kevin Markham presents 25 practical pandas techniques—including data loading, cleaning, transformation, aggregation, visualization, and performance optimization—demonstrated with real‑world datasets such as drinks, movies, Titanic, Chipotle orders, UFO sightings, and stock prices.
This guide walks you through setting up a remote Git repository, configuring IntelliJ IDEA’s Git integration, cloning a project, initializing and committing code, pushing changes, pulling updates, managing branches, handling merge conflicts, and reviewing commit history, all illustrated with clear screenshots.
This guide shows how to create a reusable pagination class for ThinkPHP 5.1, configure it in a paginate.php file, integrate it into your view templates, and style the pagination output with custom CSS.
This guide walks through installing Plotly via pip, setting up a Plotly account and credentials, configuring privacy options, and provides complete Python 2.7 code examples to generate and display interactive charts on macOS.
This guide shows how to replace outdated GET calls with a POST request to the Turing Robot API using Java's HttpClient, explains recent changes to the service, and provides a full, ready‑to‑run code example for retrieving chatbot replies.
This article introduces Python’s fundamental data types—including strings, numbers, lists, tuples, and dictionaries—explaining their characteristics, common operations, built‑in methods, and providing clear code examples for each concept; it also covers escape sequences, slicing, concatenation, formatting, and basic arithmetic operators, helping beginners grasp essential Python programming constructs.
This tutorial introduces Python's fundamental data types—including strings, numbers, lists, tuples, and dictionaries—explains their characteristics, common built‑in functions, and demonstrates practical code examples for manipulation, formatting, and conversion.
This tutorial walks you through installing Xdebug, configuring php.ini, setting up PhpStorm’s debug preferences, and using the Xdebug helper browser extension so you can pause execution at breakpoints and debug PHP code directly from your IDE.
This guide introduces thirteen entertaining Linux command‑line utilities—including sl, fortune, cowsay, cmatrix, figlet, oneko, and more—providing installation steps, usage examples, options, and visual illustrations so you can add playful effects to your terminal sessions.
This article walks through the background, monetization considerations, and detailed implementation steps—including canvas creation, enemy and player sprites, movement, collision detection, and touch handling—required to develop a basic WeChat mini‑game, with full code snippets and resource links.
This guide explains how to use the Linux grep command for powerful text searching, covering common options, file content searches, recursive scans, exclusion patterns, case‑insensitive matching, context lines, rule‑file searches, and regular‑expression techniques with practical examples.
This article introduces GraphQL as a query language for APIs, explains its history, shows how to define a schema and resolvers with graphql‑js, demonstrates query execution, error handling, built‑in types, and presents useful development tools such as GraphiQL and graphql‑import.
This article explains Vue.js computed properties and watchers, detailing their definitions, usage scenarios, code examples, differences, deep and immediate options, and when to prefer one over the other for reactive front‑end development.
This tutorial explains Python list comprehensions, showing how to replace traditional for‑loops with concise one‑line expressions for generating simple, filtered, nested, and transformed lists, complete with clear code examples and step‑by‑step explanations.
This article presents sixteen compact Python one‑liners that generate a Mandelbrot fractal, print the multiplication table, draw heart and spiral patterns, compute primes, Fibonacci numbers, quicksort, display the Zen of Python, launch a web server, simulate a slot machine, solve the N‑Queens puzzle, flatten arrays, sum the digits of 2ⁱ⁰⁰⁰, and even wish a happy birthday, each accompanied by brief explanations and visual output.
Learn how to split a lengthy image into equal‑height segments using Python’s PIL library and then recombine those pieces into an animated GIF, complete with code examples, command‑line usage, and tips for handling watermarks and unwanted overlays.
This tutorial explains the concept of visual texture, breaks down its essential elements such as overall lighting, subtle gradients, and fine details, and walks you through an eight‑step case study using Photoshop to produce a polished, high‑quality design that feels rich and tactile.
This tutorial provides a comprehensive overview of Markdown syntax, covering heading levels, text styling, unordered and ordered lists, blockquotes, inline and fenced code blocks, tables, horizontal rules, as well as link and image formatting, with clear examples for each feature.
This guide walks through the complete process of preparing a Windows Server 2016 host, enabling Hyper‑V and RRAS, installing Docker EE, configuring a transparent Docker network, and joining the node to a Kubernetes 1.9 (or 1.14) cluster, including all required commands and troubleshooting steps.
This tutorial walks you through setting up a Spring Boot 2.1.3 project using Maven, covering environment prerequisites, two creation methods (Spring Initializr and IntelliJ IDEA plugin), project structure, configuration, essential dependencies, a HelloWorld REST controller, unit testing, and important deployment tips.
The article introduces Spring Cloud Alibaba, explains its incubating status and version relationship with Spring Boot and Spring Cloud, outlines its comprehensive feature set, and shares the author’s motivation for creating a step‑by‑step tutorial series to help developers quickly adopt this China‑focused cloud-native suite.
This tutorial walks you through creating a Spring Boot project with Spring Initializr, explains its lightweight advantages, shows how to set up the project structure, configure Maven dependencies, implement a simple HTTP endpoint, and write unit tests, all using Java and Maven.
This article explains Scala's Iterator as a traversal tool rather than a collection, covering its core methods next and hasNext, demonstrating iteration with while loops, showing how to find min/max elements, obtain size, and providing a comprehensive table of common Iterator methods with code examples.
This tutorial explains how Scala treats strings as immutable Java objects, shows how to create and modify strings using literals, explicit types, and StringBuilder, demonstrates length retrieval, concatenation, formatted output, and provides a comprehensive list of java.lang.String methods usable in Scala.
This tutorial shows how a data analyst can use Python and Pillow to automatically prepare images, overlay emojis, add expressive text, and generate complete meme stickers, while also discussing layout challenges such as font sizing and line‑breaking within limited space.
This article introduces the Remote Procedure Call (RPC) protocol, outlines common Java RPC frameworks such as Thrift, Dubbo, and Spring Cloud, compares RPC with messaging queues, and provides a hands‑on tutorial for implementing a basic RPC framework to help readers understand distributed service calls.
This step‑by‑step guide explains how to connect a USB webcam to a Raspberry Pi, verify the device, install and configure the Motion daemon, and stream live video to a web browser, providing a simple DIY surveillance solution.
This article provides a comprehensive, code‑rich guide to Python decorators, covering why they are needed, how to write simple and parameterized decorators, class‑based decorators, built‑in decorators like @property and @classmethod, common pitfalls, and best‑practice optimizations using third‑party tools.
This tutorial introduces Python 3 fundamentals—including primitive data types, operators, variables, collections, control structures, functions, classes, modules, and advanced features like generators and decorators—through concise explanations and runnable code examples that let readers quickly grasp the language's core concepts.
This article demonstrates how to use Python's built-in Turtle module to create an analog clock that displays the current time, including step-by-step explanations of setting up the Turtle objects, drawing the clock face, hands, and updating them in real time with code examples.
This guide walks you through essential Git operations—including cloning repositories, managing branches, viewing logs, rolling back versions, handling file changes, and configuring user settings—so you can confidently control source code throughout the development lifecycle.
This article introduces the open‑source Chinese Java utility library Hutool, explains how to add it via Maven, demonstrates practical code examples such as HTTP form submission, HTML escaping, and scheduled tasks, and encourages developers to explore its extensive, well‑documented APIs.
This article provides a comprehensive guide to Python statements, covering assignment, function calls, control structures, loops, exception handling, and iteration techniques, complete with syntax rules, examples, and best practices for writing clean, efficient code.
This guide presents a collection of practical Python snippets covering image manipulation with Pillow, video downloading via youtube-dl, object introspection, music bot usage, financial data retrieval with Tushare, vulnerability lab setup, Beijing bus API queries, article extraction, QR code generation, fake user agents, HTTP request statistics, shell commands, Chinese text sentiment analysis, proxy handling, Zhihu API access, password breach checking, Nginx log analysis, and train ticket queries.
This article provides a step‑by‑step tutorial for beginners who want to learn Flutter, covering prerequisites, a quick Dart introduction, installing and running a Hello World app, experimenting with core widgets, UI challenges, personal tips, and a curated list of further learning resources.
This guide walks you through creating and managing Python virtual environments on Windows, showing how to specify Python 2 or Python 3 with virtualenv, activate and deactivate them, and verify the interpreter version using clear step‑by‑step instructions and screenshots.
This guide walks you through the step‑by‑step process of changing a CentOS virtual machine's hostname by editing /etc/hostname and /etc/hosts, verifying the changes, and rebooting to apply them, complete with screenshots for each stage.
This tutorial shows how to replace the default long CentOS hostname by editing /etc/hostname and /etc/hosts, verifying the changes, and rebooting the system so the new name takes effect.
This article introduces Electron Fiddle, explains how to install and run it, and demonstrates its key features such as template creation, code sharing via GitHub Gist, Monaco editor integration, and packaging apps for Windows, macOS, and Linux.
This article explains how to quickly create a JSON-RPC server using Go, implement a PHP client for verification, and discusses typical issues such as parameter formatting that arise because Go's jsonrpc package does not fully follow the JSON-RPC specification.
This article provides a concise tutorial on Python regular expression special characters, explaining the meaning and usage of symbols such as \d, \w, ^, $, *, +, ?, {n}, {n,}, {n,m}, |, [], and others, accompanied by illustrative examples and images.
This article walks through building and refining a Python regular expression that reliably matches a wide range of Chinese date formats—including year‑month‑day, year/month/day, and year‑month—explaining each component, testing against sample strings, and presenting the final pattern that captures all cases.
This article explains Python's regular expression special characters—such as \d, +, ?, {n}, and []—detailing their meanings, greedy vs. non‑greedy behavior, and how to use quantifiers and character classes effectively, complemented by illustrative examples and images.
This tutorial walks through building and refining a Python regular expression that reliably matches a wide range of Chinese date formats—such as "2018年6月7日", "2018/6/7", "2018-06-07" and "2018-06"—by explaining each component, testing against sample strings, and presenting the final concise pattern.
This tutorial explains the special regex token [\u4E00-\u9FA5] for matching Chinese characters in Python, demonstrates single and multiple character matches, shows how non‑Chinese characters and spaces affect results, and provides practical examples such as matching university names.
This article provides a concise tutorial on Python regular expression special characters, detailing the meaning and usage of symbols such as \d, ?, +, {n}, |, and others, illustrated with examples and images, helping readers quickly grasp how to match digits, whitespace, word characters, and more in pattern matching.
This article explains the meanings of Python regex tokens \w and \W, compares them with the dot operator, and demonstrates their behavior through eight step-by-step examples with visual code screenshots to help readers master pattern matching.
This comprehensive guide walks you through Python fundamentals, covering variable assignment, data types, conditional statements, loops, list and dictionary operations, as well as class definitions, object instantiation, encapsulation, and inheritance, all illustrated with clear code examples.
This tutorial explains how the special regex characters "s" and "S" work in Python, showing how "s" matches whitespace, "S" matches any non‑whitespace, and how to use quantifiers like "+" to handle multiple characters, with clear step‑by‑step examples and screenshots.
This tutorial walks you through creating a fully functional progressive web app (PWA) game using Preact, covering functional requirements, UI design, routing, component implementation, game logic, offline support, and deployment in a clear, step‑by‑step manner.
This tutorial shows how to use Python’s Turtle module to programmatically draw Captain America’s iconic shield, covering pen control, custom functions for circles and stars, and assembling the layered red, white, and blue design step by step.
This article explains why regular expressions are essential for Python web crawling, introduces the special characters ^, ., and *, and demonstrates their use with clear code examples and output screenshots, helping readers quickly grasp regex fundamentals for extracting patterns from HTML content.
This article explains why regular expressions are essential for Python web scraping, introduces the special characters ^, ., and *, and demonstrates their use with clear code examples, showing how to extract specific patterns such as numbers from HTML content.
This article shares practical Golang notes, covering compilation, package structure, basic syntax, common pitfalls like GOPATH issues, and step‑by‑step screenshots of setting up a Hello World program in Eclipse.
This tutorial walks you through installing MySQL on Ubuntu, covering command‑line installation, password configuration, service verification, and basic usage, all illustrated with screenshots to make the process clear and straightforward.
This article introduces Java annotations, explains their three main purposes—documentation, compile‑time checks, and runtime code analysis—demonstrates how to define and use custom annotations, and walks through a handcrafted ButterKnife‑like example that binds UI elements via reflection.
This article walks you through the complete installation process of Navicat for MySQL on Windows, covering download, version selection, license agreement, installation path, shortcut options, and final setup, with clear screenshots for each step.
This article shares a step‑by‑step experience of migrating a Vue‑based project to React Native for an Android delivery‑chain app, covering environment setup, debugging, common pitfalls, routing, state management, storage, hot updates, and practical code snippets to help newcomers get started quickly.
This guide walks you through every step of learning Hyperledger Fabric—from setting up the environment and deploying single‑ and multi‑node networks to developing, installing, and testing chaincode with Java SDK—providing a hands‑on roadmap for blockchain developers.
This beginner-friendly tutorial walks you through setting up Matplotlib, installing the library, and creating a variety of basic visualizations—including line plots, scatter plots, pie charts, bar charts, and histograms—while also covering multiple figures, subplots, and customization options for each chart type.
This tutorial walks through installing Flask, creating a new Python Flask project, customizing static and template directories, running the app, and integrating Bootstrap via flask‑bootstrap to build a simple web page with navigation.
This tutorial walks Python beginners through the complete process of setting up a Python interpreter in PyCharm, covering initial prompts, navigating the Project Interpreter settings, selecting an interpreter, applying changes, and troubleshooting common configuration issues.
This article explains how to use Python’s built‑in help() function to view documentation for modules, objects, and keywords, shows the command syntax, provides interactive examples, demonstrates how to browse modules, keywords and topics, and describes the simple “q” key method to exit the help session.
This tutorial explains the fundamentals of blockchain by defining block and blockchain classes in PHP, detailing fields, hash generation with SHA‑256, constructing genesis and subsequent blocks, and providing complete example code with a test run that demonstrates how each block links to its predecessor.
Nasa.js, a 25 KB open‑source framework with nearly 20 APIs for Nebulas DApp development, is now available along with a step‑by‑step learning guide and a VIP community program offering priority support and incentives.
This step‑by‑step tutorial shows how to install Ubuntu 14.04, launch PyCharm, create a new Python project, set up a virtual environment, write and run a simple script, and manage the IDE on Ubuntu, complete with screenshots for each stage.
This tutorial introduces Matplotlib, a powerful Python 2D plotting library, covering installation, basic usage, multiple figure handling, subplots, and common chart types such as line, scatter, pie, bar, and histogram with clear code examples and visual illustrations.
This article introduces DBlog, a lightweight, responsive Java blog system built with SpringBoot and Bootstrap, outlines its module structure, technology stack, key features, and provides step‑by‑step instructions for setting up the development environment, configuring the database, and running the application.
This eight‑day tutorial introduces how to quickly set up a Django‑based backend administration system, covering required dependencies, installation commands, project creation, server launch, and verification steps, encouraging readers to practice each day and eventually build an automated front‑end data entry platform.
This tutorial walks you through creating a virtual network, defining a tiny m1.nano flavor, generating key pairs, configuring security groups, launching an OpenStack instance, accessing it via a virtual console, and installing and configuring the OpenStack Horizon dashboard, complete with command examples and screenshots.
This article provides a detailed, step‑by‑step tutorial for installing Ubuntu 14.04 Desktop inside a VMware virtual machine, covering VM startup, language selection, disk setup, user configuration, and post‑installation login, complete with screenshots for each stage.
This guide explains how to create a new view in Jenkins, configure its settings, and modify the view later through the edit interface, providing step‑by‑step instructions with illustrative screenshots for effective job organization.
This guide walks through installing Docker on Ubuntu, configuring user permissions, pulling a tutorial image, setting up SSH, installing JDK and Tomcat inside the container, and exposing ports so you can access a Tomcat server via the host, demonstrating a simple PaaS setup.
This tutorial walks you through downloading Ubuntu 14.04, configuring VMware settings, allocating resources, attaching the ISO, and finalizing a fully functional Ubuntu virtual machine ready for further installation.
This guide walks through setting up Python’s Zxing library to decode QR code images, covering installation, handling 64‑bit compatibility issues, a complete script that creates temporary files, reads barcodes, logs results, and cleans up, enabling quick integration into your projects.
This guide walks Linux engineers through installing a VMware or VirtualBox virtual machine on a Windows PC, downloading the Ubuntu 18.04 64‑bit ISO, configuring hardware resources such as CPU, memory and disk, and completing the Ubuntu installation step by step, with screenshots for each stage.
This article provides a detailed, command-line tutorial for installing MySQL 5.7 on a Linux system, covering directory creation, downloading and extracting the binary package, user setup, initialization, configuration file adjustments, service startup, and password configuration.
This article introduces MongoDB, an open-source document-oriented database, outlines its key features such as indexing, sharding, and MapReduce, and provides step-by-step instructions for installing and running MongoDB on a system using Homebrew, along with basic shell commands.
An engineer from Tencent shows how to recreate Peppa Pig entirely with pure CSS by exploiting the border‑radius property to craft ellipses, rotate them, layer colors, and mask gaps, providing step‑by‑step code for each body part and a complete, animated illustration.
This guide presents a complete reference of Vim commands—including history navigation, file handling, mode switching, cursor movement, searching, replacing, undo/redo, copying, pasting, window management, macro recording, shell execution, commenting, and help—so users can master efficient text editing in Vim across Unix and Windows environments.
This tutorial explains how JavaScript ES6 Proxies work, demonstrates creating a Proxy with get, set, and deleteProperty traps, and walks through rebuilding the on‑change library to monitor object and array mutations, including handling deep nesting and common pitfalls.
Explore the essential C programming concepts—from basic data types, constants, and variables to complex structures, unions, enums, and pointers—through clear explanations, practical examples, and code snippets, helping beginners understand memory allocation, type definitions, and safe coding practices.
This article introduces Play‑with‑Docker, a browser‑based sandbox that lets users instantly create Docker servers, use an integrated SSH client, automatically map ports, and deploy multi‑node Swarm clusters without installing anything locally, providing a fast, hands‑on way to learn Docker fundamentals.
This tutorial explains the fundamentals of Proof‑of‑Stake, compares it with Proof‑of‑Work, and provides a step‑by‑step Go implementation of a PoS blockchain with TCP networking, validator selection, and code snippets for building and running the system.
This guide walks through Python’s core data structures—strings, lists, tuples, dictionaries, and sets—detailing their creation, common built‑in methods, slicing, updating, and iteration with clear code examples, helping readers master essential operations for effective data manipulation.
This article provides a detailed, step‑by‑step tutorial for downloading, installing, and configuring the FileZilla FTP client and server on Windows, including screenshots of each installation stage and tips for creating desktop shortcuts and launching the program.
This article combines humorous blockchain anecdotes with a clear, illustrated explanation of blockchain fundamentals and a complete Python tutorial that walks you through creating a blockchain, implementing proof‑of‑work, exposing it via Flask APIs, and handling node consensus.
This tutorial shows how to wrap the jsonplaceholder REST service with a GraphQL layer in Go, covering data models, schema creation, resolver functions, server setup, and example queries with results.
This article provides a comprehensive tutorial on installing and using PuTTY on Windows, covering its key features, download process, and detailed step‑by‑step instructions with screenshots to securely connect to remote servers via SSH.
This tutorial walks you through installing Flask, creating a simple "Hello Flask" app, enabling debug mode, defining routes and path variables, building URLs, handling HTTP methods, static files, templates, logging, request data, file uploads, cookies, redirects, responses, and sessions, providing clear code examples for each feature.
This tutorial walks through creating a basic Java blockchain that includes block structures, transaction modeling, a proof‑of‑work mining process with configurable difficulty, and functions to compute wallet balances, providing complete source code and explanatory diagrams.
JSONPath, analogous to XPath for XML, enables efficient querying of JSON data; this article introduces its concepts, demonstrates how to integrate Fastjson's JSONPath in Java, provides syntax examples, and showcases a simple code demonstration with expected output.
This tutorial demonstrates how to install PyMySQL, establish a MySQL connection in Python, and perform table creation, data insertion, and query operations using example code, while outlining required prerequisites such as credentials and database details.
Learn step‑by‑step how to modify a CentOS virtual machine’s hostname by editing /etc/hostname and /etc/hosts, verifying changes with cat, and restarting the system to apply the new name, with clear screenshots and tips for avoiding common pitfalls.
