Compatibility relations on codes and free monoids
Kärki, Tomi
RAIRO - Theoretical Informatics and Applications - Informatique Théorique et Applications, Tome 42 (2008), p. 539-552 / Harvested from Numdam

A compatibility relation on letters induces a reflexive and symmetric relation on words of equal length. We consider these word relations with respect to the theory of variable length codes and free monoids. We define an (R,S)-code and an (R,S)-free monoid for arbitrary word relations R and S. Modified Sardinas-Patterson algorithm is presented for testing whether finite sets of words are (R,S)-codes. Coding capabilities of relational codes are measured algorithmically by finding minimal and maximal relations. We generalize the stability criterion of Schützenberger and Tilson’s closure result for (R,S)-free monoids. The (R,S)-free hull of a set of words is introduced and we show how it can be computed. We prove a defect theorem for (R,S)-free hulls. In addition, a defect theorem of partial words is proved as a corollary.

Publié le : 2008-01-01
DOI : https://doi.org/10.1051/ita:2008016
Classification:  68R15
@article{ITA_2008__42_3_539_0,
     author = {K\"arki, Tomi},
     title = {Compatibility relations on codes and free monoids},
     journal = {RAIRO - Theoretical Informatics and Applications - Informatique Th\'eorique et Applications},
     volume = {42},
     year = {2008},
     pages = {539-552},
     doi = {10.1051/ita:2008016},
     mrnumber = {2434034},
     zbl = {1149.68069},
     language = {en},
     url = {http://dml.mathdoc.fr/item/ITA_2008__42_3_539_0}
}
Kärki, Tomi. Compatibility relations on codes and free monoids. RAIRO - Theoretical Informatics and Applications - Informatique Théorique et Applications, Tome 42 (2008) pp. 539-552. doi : 10.1051/ita:2008016. http://gdmltest.u-ga.fr/item/ITA_2008__42_3_539_0/

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