[Formula: see text]A hyperbolic code is an evaluation code that improves a Reed–Muller code because the dimension increases while the minimum distance is not penalized. We give necessary and sufficient conditions, based on the basic parameters of the Reed–Muller code, to determine whether a Reed–Muller code coincides with a hyperbolic code. Given a hyperbolic code [Formula: see text], we find the largest Reed–Muller code contained in [Formula: see text] and the smallest Reed–Muller code containing [Formula: see text]. We then prove that similar to Reed–Muller and affine Cartesian codes, the [Formula: see text]th generalized Hamming weight and the [Formula: see text]th footprint of the hyperbolic code coincide. Unlike for Reed–Muller and affine Cartesian codes, determining the [Formula: see text]th footprint of a hyperbolic code is still an open problem. We give upper and lower bounds for the [Formula: see text]th footprint of a hyperbolic code that, sometimes, are sharp.
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This content will become publicly available on December 1, 2026
Codes with hierarchical locality on Artin–Schreier surfaces
In this paper, we construct codes with hierarchical locality using natural geometric structures in Artin–Schreier surfaces of the form [Formula: see text]. Our main theorem describes the codes, their hierarchical structure and recovery algorithms, and gives parameters. We also develop a family of examples using codes defined over [Formula: see text] on the surface [Formula: see text]. We use elementary methods to count the [Formula: see text]-rational points on the surface, enabling us to provide explicit hierarchical parameters and a better bound on minimum distance for these codes. An additional example and some generalizations are also considered.
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- Award ID(s):
- 2137661
- PAR ID:
- 10656445
- Publisher / Repository:
- World Scientific
- Date Published:
- Journal Name:
- Journal of Algebra and Its Applications
- Volume:
- 24
- Issue:
- 13n14
- ISSN:
- 0219-4988
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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