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On the Expressive Power of Multiple Heads in CHR [article]

Cinzia Di Giusto, Maurizio Gabbrielli, Maria Chiara Meo
2011 arXiv   pre-print
These results provide a formal proof for the claim that multiple heads augment the expressive power of the CHR language.  ...  Many empirical evidences suggest that multiple heads augment the expressive power of the language, however no formal result in this direction has been proved, so far.  ...  Acknowledgments We than the reviewers for their precise and helpful comments.  ... 
arXiv:0804.3351v6 fatcat:v4mceacj2fbtliycjrsjt6mmfa

Expressiveness of Multiple Heads in CHR [chapter]

Cinzia Di Giusto, Maurizio Gabbrielli, Maria Chiara Meo
2009 Lecture Notes in Computer Science  
Therefore, since restricting to single head rules does not affect the Turing completeness of the language, one can legitimately ask whether multiple heads do indeed augment the expressive power of the  ...  On the other hand, the presence of multiples heads complicates considerably the semantics.  ...  With this situation one could legitimately ask whether one can formally prove that multiple heads do indeed augment the expressive power of the language.  ... 
doi:10.1007/978-3-540-95891-8_21 fatcat:sy2bolpwvrddri3gjdxt65hgza

Turing-Complete Subclasses of CHR [chapter]

Jon Sneyers
2008 Lecture Notes in Computer Science  
Interesting subclasses of CHR are still Turing-complete: CHR with only one kind of rule, with only one rule, and propositional refined CHR.  ...  Single-headed CHR without host language and propositional abstract CHR are not Turing-complete.  ...  This research was funded by a Ph.D. grant of the Institute for the Promotion of Innovation through Science and Technology in Flanders (IWT-Vlaanderen).  ... 
doi:10.1007/978-3-540-89982-2_72 fatcat:mr7zeqh24bdrvc5vnp55ag3qoi

Automating Termination Proofs for CHR [chapter]

Paolo Pilozzi, Danny De Schreye
2009 Lecture Notes in Computer Science  
Similar to such approaches for Logic Programming (LP), we define a symbolic level mapping on atoms of the program and express termination conditions using these.  ...  However, different from the approaches developed for LP, termination of CHR programs is concerned with multi-headed rules, while the existing constraint-based approaches in LP are developed for definite  ...  Table 1 . 1 Results in seconds of CHRisTA on terminating CHR programs ackermann − constr02 1.43 constr15 7.85 f ib 1.53 pathc − average 1.40 constr03 1.52 constr16 3.47 gcd 1.43 power 1.64 binlog  ... 
doi:10.1007/978-3-642-02846-5_43 fatcat:iramzdag6ve7dc6cqbpgbuf7oi

Aggregates for CHR through Program Transformation [chapter]

Peter Van Weert, Jon Sneyers, Bart Demoen
2008 Lecture Notes in Computer Science  
This new feature significantly improves the conciseness and expressiveness of the language.  ...  In this paper, we describe an implementation based on source-to-source transformations to CHR (extended with some low-level compiler directives).  ...  This declarative language feature allows the aggregation of information from an unbounded number of constraints to be captured concisely in a single expression in the head of a CHR rule.  ... 
doi:10.1007/978-3-540-78769-3_5 fatcat:fomavtehlza7deep6wbxybasgm

Compiling Constraint Handling Rules into Prolog with Attributed Variables [chapter]

Christian Holzbaur, Thom Frühwirth
1999 Lecture Notes in Computer Science  
We introduce the most recent and advanced implementation of constraint handling rules (CHR) in a logic programming language, which improves both on previous implementations (in terms of completeness, exibility  ...  and e ciency) and on the principles that should guide such a Prolog implementation consisting of a runtime system and a compiler.  ...  In another sense, CHR are more general, since they allow for multiple heads, i.e. conjunctions of constraints in the head of a rule.  ... 
doi:10.1007/10704567_7 fatcat:ujk5fenv4vej7aiandewipdoui

A Linear-Logic Semantics for Constraint Handling Rules [chapter]

Hariolf Betz, Thom Frühwirth
2005 Lecture Notes in Computer Science  
One of the attractive features of the Constraint Handling Rules (CHR) programming language is its declarative semantics where rules are read as formulae in first-order predicate logic.  ...  However, the more CHR is used as a general-purpose programming language, the more the limitations of that kind of declarative semantics in modelling change become apparent.  ...  Coin) by committing to one of the rules, thereby equating either head or tail with the variable Coin.  ... 
doi:10.1007/11564751_13 fatcat:ih6mm7u2dbe57kg6uxnghgsdp4

Decidability properties for fragments of CHR

MAURIZIO GABBRIELLI, JACOPO MAURO, MARIA CHIARA MEO, JON SNEYERS
2010 Theory and Practice of Logic Programming  
The first CHR dialect allows onlyrange-restrictedrules, that is, it does not allow the use of variables in the body or in the guard of a rule if they do not appear in the head.  ...  We show that the existence of an infinite computation is decidable for this dialect. The second dialect instead limits the number of atoms in the head of rules to one.  ...  The number of atoms in the heads also affects the expressive power of the language.  ... 
doi:10.1017/s1471068410000311 fatcat:xpud4quclbd7fgtp3eooiwi3gq

Lead Modulates trans- and cis-Expression Quantitative Trait Loci (eQTLs) in Drosophila melanogaster Heads

Wen Qu, Katherine Gurdziel, Roger Pique-Regi, Douglas M. Ruden
2018 Frontiers in Genetics  
We noticed that the genes associated with one of the 14 detected trans-eQTL hotspots, Chr 2L: 6,250,000 could be roughly divided into two groups based on their differential expression profile patterns  ...  The expression of all the associated genes in the trans-eQTL hotspot was visualized with hierarchical clustering analysis.  ...  Stuart Macdonald from the University of Kansas and Dr. Anthony Long from the University of California, Irvine.  ... 
doi:10.3389/fgene.2018.00395 pmid:30294342 pmcid:PMC6158337 fatcat:3fd6p4ylujainmen3cdmev4siy

Genetic analysis of complex traits in the emerging Collaborative Cross

David L. Aylor, William Valdar, Wendy Foulds-Mathes, Ryan J. Buus, Ricardo A. Verdugo, Ralph S. Baric, Martin T. Ferris, Jeff A. Frelinger, Mark Heise, Matt B. Frieman, Lisa E. Gralinski, Timothy A. Bell (+29 others)
2011 Genome Research  
The number of expression QTLs discovered here exceeds all previous efforts at eQTL mapping in mice, and we map local eQTL at 1-Mb resolution.  ...  Analysis based on inferred haplotypes improves power, reduces false discovery, and provides information to identify and prioritize candidate genes that is unique to multifounder crosses like the CC.  ...  Essential support was also provided by the Dean of the UNC School of Medicine, the Lineberger Comprehensive Cancer Center at UNC, and the University Cancer Research Fund from the state of North Carolina  ... 
doi:10.1101/gr.111310.110 pmid:21406540 pmcid:PMC3149489 fatcat:5ulfuwbosbcipnozwdns6oou4a

Kinesin Family Member 12 Is a Candidate Polycystic Kidney Disease Modifier in the cpk Mouse

M. Mrug
2005 Journal of the American Society of Nephrology  
Candidate genes were identified within the QTL intervals on the basis of expression profiling, reverse transcriptase-PCR, haplotypes, and sequence analysis.  ...  Genome-wide scan identified a major effect QTL on chromosome (Chr) 4 for the renal traits, adjusted BDA, and cholangitis with logarithm of odds scores of 18, 8, and 5, respectively.  ...  In addition to the Chr 4 QTL, multiple regression modeling confirmed a significant QTL on Chr 13 (Table 3 , Figure 4B ), as well as two sets of interactions between Chr 1 at 62 cM and Chr 2 at 96 cM  ... 
doi:10.1681/asn.2004121083 pmid:15728779 fatcat:x242m2xqjzezzgkrq34sbgpddq

Constraint Handling Rules - What Else? [chapter]

Thom Frühwirth
2015 Lecture Notes in Computer Science  
Up-to-date information on CHR can be found online at the CHR web-page www. constraint-handling-rules.org, including the slides of the keynote talk associated with this article.  ...  Applications of CHR and research using CHR are discussed in Section 6.  ...  of CHR can be considered essential, since they increase the expressive power of CHR: constraints with arguments, builtin constraints, function symbols to build complex terms, multi-headed rules, introduction  ... 
doi:10.1007/978-3-319-21542-6_2 fatcat:jvm4bxr2wfdp7lyrgxttapekwq

Theory and practice of constraint handling rules

Thom Frühwirth
1998 The Journal of Logic Programming  
This survey then describes implementations of the language before we review several constraint solvers ± both traditional and nonstandard ones ± written in the CHR language.  ...  CHR are essentially a committedchoice language consisting of multi-headed gurded rules that rewrite constraints into simpler ones until they are solved.  ...  One should compare this to the standard concurrent program as given in [81] to appreciate the expressive power of multiple heads. It is about three times as long.  ... 
doi:10.1016/s0743-1066(98)10005-5 fatcat:6x3qpbx3yva5nljfbrrgrtgvem

CLP projection for constraint handling rules

Remy Haemmerle, Pedro Lopez-Garcia, Manuel V. Hermenegildo
2011 Proceedings of the 13th international ACM SIGPLAN symposium on Principles and practices of declarative programming - PPDP '11  
Finally, we illustrate how the notion of CLP projection can be used in practice to apply CLP analyzers to CHR.  ...  The CLP projection consists of a naive translation of CHR programs into Constraint Logic Programs (CLP).  ...  For instance, the following derivation cannot be extended: In spite of its weaknesses in treating guarded multi-headed programs -indeed the termination of most of multi-headed programs relies on the multiplicity  ... 
doi:10.1145/2003476.2003496 dblp:conf/ppdp/HaemmerleLH11 fatcat:y3ylih4qfrbcldox74hmlf66b4

Aggregates in Constraint Handling Rules [chapter]

Jon Sneyers, Peter Van Weert, Tom Schrijvers, Bart Demoen
2007 Lecture Notes in Computer Science  
Moreover, in our proposal, no restrictions are placed on aggregate expressions: aggregates may range over arbitrary guarded conjunctions of constraints; even nested aggregates are allowed.  ...  The proposed extension features nested aggregate expressions over guarded conjunctions of constraints, a series of predefined aggregates, and application-tailored user-defined aggregates.  ...  Duck for the many discussions and valuable input in the initial stages of this research. We are grateful to the anonymous referees of ICLP 2007 for their comments on an earlier version of this paper.  ... 
doi:10.1007/978-3-540-74610-2_39 fatcat:aqrfhj2r3zbbbd7eud5hfpb5rq
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