What Can Vectorised Trees Do for You? // Asher Harvey-Smith // DYNA Fall 2025

Representing hierarchical data structures (trees) with vectors is trendy in some parts of the APL world, but just how useful is it? Asher introduces the basic tree-wrangling operations and walks through some case studies, exploring why we should (or shouldn’t!) be using this technique. 00:00 About Asher 02:07 Representing tree structures 07:04 Examples of operations on trees 09:57 When parent vectors are useful 11:42 Case study: Co-dfns and static analysis 12:25 Case study: File system queries 15:38 Case study: Particle simulation 18:56 Case study: Disjoint set data structure 21:15 Conclusion 22:25 Questions This video is part of a series of presentations from DYNA Fall 2025 which was held in New York City on Monday 29 and Tuesday 30 September 2025. More information about this event: https://dyna.dyalog.com About the Presenter Asher discovered APL while he was at university, and loves to make complicated algorithms neat and fast using array-oriented thinking. He spent two summers as an intern at Dyalog Ltd, working as both an APL implementer and evangelist, before joining as a full-time member of Team Dyalog in 2025. About Dyalog Ltd We are the creators of Dyalog APL, a powerful array-oriented programming language designed for concise, expressive problem solving. Our team is dedicated to its ongoing development and long-term maintenance, ensuring it continues to meet the evolving needs of our users. To support this, we provide a suite of development tools and environments that enable both Subject Matter Experts and IT professionals to rapidly turn complex ideas into robust, efficient software solutions. -------------------- Get Started Download the latest version of Dyalog, free for personal or non-commercial use: https://www.dyalog.com/downloads -------------------- #DYNA #APLProgramming #DataStructures #Dyalog #ArrayProgramming #VectorisedTrees #FunctionalProgramming #TreeStructures #HierarchicalData #ProgrammingLanguages #APLCommunity