Articles
Published 2018-05-31
Keywords
- splines of degree one,
- splines with free knots,
- best approximation,
- discrete approx- imation,
- Lp-approximation (1 ≤ p ≤ ∞)
- existence theorem,
- first-degree splines,
- broken lines ...More
How to Cite
Kunath, J., & Cromme, L. J. (2018). Discrete Approximation by First-Degree Splines with Free Knots. International Journal For Research In Mathematics And Statistics, 4(5), 26–39. https://doi.org/10.53555/ms.v4i5.621
Copyright (c) 2018 International Journal For Research In Mathematics And Statistics (ISSN: 2208-2662)

This work is licensed under a Creative Commons Attribution-NonCommercial-NoDerivatives 4.0 International License.
Abstract
This paper deals with the approximation of discrete real-valued functions by first-degree splines (broken lines) with free knots for arbitrary Lp-norms (1 ≤ p ≤ ∞). We prove the existence of best approximations und derive statements on the position of the (free) knots of a best approximation. Building on this, elsewhere we develop an algorithm to determine a (global) best approximation in the L2-norm.
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References
- Cromme, L. J., Kunath, J., Krebs, A.: Computing best discrete least-squares approximations by first-degree splines with free knots. Preprint at https://arxiv.org (2017).
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