CppNumericalSolvers is a header-only C++17 library for numerical optimization that provides a suite of modern solvers for both unconstrained and constrained problems. The library features a sophisticated expression template system for building complex objective functions, implementations of popular algorithms like L-BFGS, BFGS, and Newton's method, and advanced constrained optimization via the Augmented Lagrangian method. It uses Eigen3 as its sole dependency for linear algebra operations and is designed for easy integration into other projects. The architecture is modular with separate components for function interfaces, solvers, line searches, and utilities, all leveraging C++ templates for flexibility and performance.
Legacy Notepad is a Windows desktop text editor application built with C++17 and Win32 API as a lightweight alternative to Notepad.exe. It features multi-language support (English/Japanese), multi-encoding text handling (UTF-8, UTF-8 BOM, UTF-16 LE/BE, ANSI), rich editing capabilities (word wrap, font selection, zoom, time/date stamp, find/replace/goto), background image support with multiple positioning modes and opacity control, always-on-top window pinning, printing functionality, and customizable application icons. The architecture follows a modular monolithic structure with separate modules for theme, background, file I/O, editor, UI, dialogs, commands, menu, and settings, coordinated through a Win32 message loop in main.cpp.