# Binary operations on automatic functions

Juhani Karhumäki; Jarkko Kari; Joachim Kupke^{[1]}

- [1] ETH Zurich, Switzerland;

RAIRO - Theoretical Informatics and Applications - Informatique Théorique et Applications (2008)

- Volume: 42, Issue: 2, page 217-236
- ISSN: 0988-3754

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topKarhumäki, Juhani, Kari, Jarkko, and Kupke, Joachim. "Binary operations on automatic functions." RAIRO - Theoretical Informatics and Applications - Informatique Théorique et Applications 42.2 (2008): 217-236. <http://eudml.org/doc/245544>.

@article{Karhumäki2008,

abstract = {Real functions on the domain $[0,1)^n$ – often used to describe digital images – allow for different well-known types of binary operations. In this note, we recapitulate how weighted finite automata can be used in order to represent those functions and how certain binary operations are reflected in the theory of these automata. Different types of products of automata are employed, including the seldomly-used full cartesian product. We show, however, the infeasibility of functional composition; simple examples yield that the class of automatic functions (i.e., functions computable by automata) is not closed under this operation.},

affiliation = {ETH Zurich, Switzerland;},

author = {Karhumäki, Juhani, Kari, Jarkko, Kupke, Joachim},

journal = {RAIRO - Theoretical Informatics and Applications - Informatique Théorique et Applications},

keywords = {automatic functions; weighted finite automata; full cartesian product; digital images},

language = {eng},

number = {2},

pages = {217-236},

publisher = {EDP-Sciences},

title = {Binary operations on automatic functions},

url = {http://eudml.org/doc/245544},

volume = {42},

year = {2008},

}

TY - JOUR

AU - Karhumäki, Juhani

AU - Kari, Jarkko

AU - Kupke, Joachim

TI - Binary operations on automatic functions

JO - RAIRO - Theoretical Informatics and Applications - Informatique Théorique et Applications

PY - 2008

PB - EDP-Sciences

VL - 42

IS - 2

SP - 217

EP - 236

AB - Real functions on the domain $[0,1)^n$ – often used to describe digital images – allow for different well-known types of binary operations. In this note, we recapitulate how weighted finite automata can be used in order to represent those functions and how certain binary operations are reflected in the theory of these automata. Different types of products of automata are employed, including the seldomly-used full cartesian product. We show, however, the infeasibility of functional composition; simple examples yield that the class of automatic functions (i.e., functions computable by automata) is not closed under this operation.

LA - eng

KW - automatic functions; weighted finite automata; full cartesian product; digital images

UR - http://eudml.org/doc/245544

ER -

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