P1-KAN: an effective Kolmogorov-Arnold network with application to hydraulic valley optimization
Xavier Warin
TL;DR
This paper addresses the challenge of high-dimensional function approximation, especially for irregular functions, by introducing P1-KAN, a layered Kolmogorov-Arnold network using 1D finite-element-like bases. It provides rigorous convergence bounds under Lipschitz outer functions and universal approximation theorems, including both adaptation-enabled and non-adaptation variants, and demonstrates empirical strength against MLPs and other KANs on synthetic functions. The method is further validated through a hydraulic valley optimization case, where P1-KAN with adapting lattices achieves faster convergence and robust performance, approaching or surpassing spline-based KAN in irregular regimes. Overall, P1-KAN offers a theoretically grounded, practically effective framework for high-dimensional, potentially irregular function approximation and stochastic optimization in engineering applications.
Abstract
A new Kolmogorov-Arnold network (KAN) is proposed to approximate potentially irregular functions in high dimensions. We provide error bounds for this approximation, assuming that the Kolmogorov-Arnold expansion functions are sufficiently smooth. When the function is only continuous, we also provide universal approximation theorems. We show that it outperforms multilayer perceptrons in terms of accuracy and convergence speed. We also compare it with several proposed KAN networks: it outperforms all networks for irregular functions and achieves similar accuracy to the original spline-based KAN network for smooth functions. Finally, we compare some of the KAN networks in optimizing a French hydraulic valley.
