Shell Scripting Tutorial: How to Handle the Same Command-Line Option Multiple Times

When writing shell scripts, handling command-line options effectively is essential. A common scenario developers encounter is needing to process the same command-line option multiple times within a script. While many basic tutorials cover simple option parsing, fewer resources explain clearly how to handle repeated options. This tutorial will demonstrate how to process a repeated option multiple times in your shell script clearly and effectively. We’ll cover the most common tools (getopts, manual parsing, and advanced parsing using getopt) and provide practical examples and insights to help you choose the best solution for your situation. ...

March 19, 2025 · 4 min · 817 words · vNotedAi

Why Linear Regression Struggles with Walk-Forward Validation (and How to Address It)

Linear regression is a classic, intuitive prediction method widely used across data science tasks. However, when evaluated using walk-forward validation—a common testing approach for time series forecasting—the performance of linear regression models often falls short. If you’ve encountered poor results from linear regression in your walk-forward validation tests, you’re not alone. In this tutorial-style post, we’ll explore why linear regression tends to perform poorly under walk-forward validation, analyze the reasons behind this behavior, and provide actionable tips to improve your forecasting accuracy. ...

March 17, 2025 · 5 min · 909 words · vNotedAi

Exploring crystalruby: Embed Crystal Code Directly in Ruby for Performance Gains

Ruby developers have long admired the language for its simplicity, readability, and elegance. However, performance-critical applications sometimes demand more speed than pure Ruby can comfortably deliver. Crystal, a language inspired by Ruby, brings compiled performance with Ruby-like syntax and developer-friendly features. But integrating Crystal code directly into Ruby has traditionally involved cumbersome workflow, until now. Enter crystalruby, a trending Ruby gem that enables embedding Crystal code directly within Ruby scripts. In this post, we’ll dive into what crystalruby is, why it matters, and how you can leverage it to significantly boost your Ruby application’s performance. ...

March 14, 2025 · 4 min · 736 words · vNotedAi

Raspberry Pi Fails to Boot Depending on Outlet: Troubleshooting and Solutions

Have you ever experienced your Raspberry Pi booting normally from one electrical outlet, only to find it failing to start up when plugged into another outlet? While this issue might initially seem bizarre or trivial, inconsistent boot behavior depending on power outlets can indicate underlying electrical or power supply problems. Ensuring your Raspberry Pi receives stable and reliable power is critical—not only for booting but also for long-term device stability and reliability. ...

March 12, 2025 · 4 min · 825 words · vNotedAi

PostgreSQL Performance Tuning Deep Dive: Best Practices for Optimal Database Efficiency

PostgreSQL is one of the most powerful and widely-used open-source relational databases in the industry. Its flexibility, scalability, and robust feature set make it a top choice for organizations of all sizes. However, as your data grows and workloads intensify, it’s essential to ensure your PostgreSQL instance is optimized for peak performance. This comprehensive guide will provide industry insights and practical best practices for performance tuning your PostgreSQL database, helping you to maintain optimal efficiency, reliability, and speed. ...

March 10, 2025 · 4 min · 828 words · vNotedAi