Saved in:
Bibliographic Details
Main Authors: Bossu, Sebastien, Papanicolaou, Andrew, Hatto, Nour El
Format: Preprint
Published: 2025
Subjects:
Online Access:https://arxiv.org/abs/2510.16148
Tags: Add Tag
No Tags, Be the first to tag this record!
Table of Contents:
  • We analyze the problem of fitting a fonction en escalier or multi-step function to a curve in L^2 Hilbert space. We propose a two-stage optimization approach whereby the step positions are initially fixed, corresponding to a classic linear least-squares problem with closed-form solution, and then are allowed to vary, leading to first-order conditions that can be solved recursively. We find that, subject to regularity conditions, the speed of convergence is linear as the number of steps $n$ goes to infinity, and we develop a simple algorithm to recover the global optimum fit. Our numerical results based on a sweep search implementation show promising performance in terms of speed and accuracy.