Loading…

Bad news on decision problems for patterns

We study the inclusion problem for pattern languages, which - due to Jiang et al. (Journal of Computer and System Sciences 50, 1995) - is known to be undecidable. More precisely, Jiang et al. demonstrate that there is no effective procedure deciding the inclusion for the class of all pattern languag...

Full description

Saved in:
Bibliographic Details
Main Authors: Dominik Freydenberger, Daniel Reidenbach
Format: Default Article
Published: 2010
Subjects:
Online Access:https://hdl.handle.net/2134/5593
Tags: Add Tag
No Tags, Be the first to tag this record!
_version_ 1823271280261988352
author Dominik Freydenberger
Daniel Reidenbach
author_facet Dominik Freydenberger
Daniel Reidenbach
author_sort Dominik Freydenberger (3718891)
collection Figshare
description We study the inclusion problem for pattern languages, which - due to Jiang et al. (Journal of Computer and System Sciences 50, 1995) - is known to be undecidable. More precisely, Jiang et al. demonstrate that there is no effective procedure deciding the inclusion for the class of all pattern languages over all alphabets. Most applications of pattern languages, however, consider classes over fixed alphabets, and therefore it is practically more relevant to ask for the existence of alphabet-specific decision procedures. Our first main result states that, for all but very particular cases, this version of the inclusion problem is also undecidable. The second main part of our paper disproves the prevalent conjecture on the inclusion of so-called similar E-pattern languages, and it explains the devastating consequences of this result for the intensive previous research on the most prominent open decision problem for pattern languages, namely the equivalence problem for general E-pattern languages.
format Default
Article
id rr-article-9402878
institution Loughborough University
publishDate 2010
record_format Figshare
spelling rr-article-94028782010-01-01T00:00:00Z Bad news on decision problems for patterns Dominik Freydenberger (3718891) Daniel Reidenbach (1256598) Other information and computing sciences not elsewhere classified untagged Information and Computing Sciences not elsewhere classified We study the inclusion problem for pattern languages, which - due to Jiang et al. (Journal of Computer and System Sciences 50, 1995) - is known to be undecidable. More precisely, Jiang et al. demonstrate that there is no effective procedure deciding the inclusion for the class of all pattern languages over all alphabets. Most applications of pattern languages, however, consider classes over fixed alphabets, and therefore it is practically more relevant to ask for the existence of alphabet-specific decision procedures. Our first main result states that, for all but very particular cases, this version of the inclusion problem is also undecidable. The second main part of our paper disproves the prevalent conjecture on the inclusion of so-called similar E-pattern languages, and it explains the devastating consequences of this result for the intensive previous research on the most prominent open decision problem for pattern languages, namely the equivalence problem for general E-pattern languages. 2010-01-01T00:00:00Z Text Journal contribution 2134/5593 https://figshare.com/articles/journal_contribution/Bad_news_on_decision_problems_for_patterns/9402878 CC BY-NC-ND 4.0
spellingShingle Other information and computing sciences not elsewhere classified
untagged
Information and Computing Sciences not elsewhere classified
Dominik Freydenberger
Daniel Reidenbach
Bad news on decision problems for patterns
title Bad news on decision problems for patterns
title_full Bad news on decision problems for patterns
title_fullStr Bad news on decision problems for patterns
title_full_unstemmed Bad news on decision problems for patterns
title_short Bad news on decision problems for patterns
title_sort bad news on decision problems for patterns
topic Other information and computing sciences not elsewhere classified
untagged
Information and Computing Sciences not elsewhere classified
url https://hdl.handle.net/2134/5593