AbsInf: A Lightweight Object to Represent float('inf') in Dijkstra's Algorithm

Abstract

We introduce AbsInf, a lightweight abstract object designed as a high-performance alternative to Python's native float('inf') within pathfinding algorithms. Implemented as a C-based Python extension, AbsInf bypasses IEEE-754 float coercion and dynamic type dispatch, offering constant-time dominance comparisons and arithmetic neutrality. When integrated into Dijkstra's algorithm without altering its logic, AbsInf reduces runtime by up to 17.2%, averaging 9.74% across diverse synthetic and real-world graph datasets. This optimization highlights the performance trade-offs in high-frequency algorithmic constructs, where a symbolic use of infinity permits efficient abstraction. Our findings contribute to the broader discourse on lightweight architectural enhancements for interpreted languages, particularly in performance-critical control flows.