This paper describes Nancy, a Network Calculus (NC) library that allows users to perform complex min-plus and max-plus algebra operations efficiently. To the best of our knowledge, Nancy is the only open-source library that implements operations working on arbitrary piecewise affine functions, as well as to implement some of them (e.g. sub-additive closure and function composition). Nancy allows researchers to compute NC results using a straightforward syntax, which matches the algebraic one. Moreover, it is designed having computational efficiency in mind: it exploits optimizations of data structures, it uses inheritance to allow for faster algorithms when they are available (e.g., for specific subclasses of functions), and it is natively parallel, thus reaping the benefit of multicore hardware. This makes it usable to solve NC problems which were previously considered beyond the realm of tractable.

翻译：本文介绍Nancy——一种网络演算（NC）库，使用户能高效执行复杂的min-plus与max-plus代数运算。据我们所知，Nancy是唯一实现任意分段仿射函数运算的开源库，同时实现了子加法闭包与函数复合等部分运算。该库允许研究者通过简洁的语法（与代数表达式一致）计算NC结果。此外，其设计聚焦计算效率：通过优化数据结构、利用继承机制（当存在更快的算法时，如针对特定函数子类）加速运算，并原生支持并行化，从而充分发挥多核硬件的优势。这使得原本被认为超出可解范围的NC问题得以求解。