Search results for "points"

showing 10 items of 415 documents

On fixed points of the Burrows-Wheeler transform

2017

The Burrows-Wheeler Transform is a well known transformation widely used in Data Compression: important competitive compression software, such as Bzip (cf. [1]) and Szip (cf. [2]) and some indexing software, like the FM-index (cf. [3]), are deeply based on the Burrows Wheeler Transform. The main advantage of using BWT for data compression consists in its feature of "clustering" together equal characters. In this paper we show the existence of fixed points of BWT, i.e., words on which BWT has no effect. We show a characterization of the permutations associated to BWT of fixed points and we give the explicit form of fixed points on a binary ordered alphabet a, b having at most four b's and th…

Discrete mathematicsAlgebra and Number TheoryBurrows–Wheeler transformSettore INF/01 - InformaticaPermutationPermutations0102 computer and information sciences02 engineering and technologyInformation SystemFixed point01 natural sciencesTheoretical Computer ScienceComputational Theory and Mathematics010201 computation theory & mathematicsFixed PointFixed Points0202 electrical engineering electronic engineering information engineeringBurrows-Wheeler Transform; Fixed Points; Permutations; Theoretical Computer Science; Algebra and Number Theory; Information Systems; Computational Theory and Mathematics020201 artificial intelligence & image processingBurrows-Wheeler TransformInformation SystemsMathematics
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Common Fixed Points in a Partially Ordered Partial Metric Space

2013

In the first part of this paper, we prove some generalized versions of the result of Matthews in (Matthews, 1994) using different types of conditions in partially ordered partial metric spaces for dominated self-mappings or in partial metric spaces for self-mappings. In the second part, using our results, we deduce a characterization of partial metric 0-completeness in terms of fixed point theory. This result extends the Subrahmanyam characterization of metric completeness.

Discrete mathematicsArticle SubjectInjective metric spacelcsh:MathematicsEquivalence of metricslcsh:QA1-939Fixed points dominated self-mappings 0-completenessConvex metric spaceIntrinsic metricCombinatoricsMetric spaceSettore MAT/05 - Analisi MatematicaMetric (mathematics)Metric differentialFisher information metricMathematicsInternational Journal of Analysis
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Common fixed points in generalized metric spaces

2012

Abstract We establish some common fixed point theorems for mappings satisfying a ( ψ , φ ) -weakly contractive condition in generalized metric spaces. Presented theorems extend and generalize many existing results in the literature.

Discrete mathematicsComputational MathematicsMetric spaceFixed-point iterationSettore MAT/05 - Analisi MatematicaApplied MathematicsGeneralized metric weakly contractive condition contraction of integral type fixed point common fixed points.Common fixed pointProduct metricFixed pointIntrinsic metricMathematicsConvex metric space
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Common fixed points for discontinuous mappings in fuzzy metric spaces

2008

In this paper we prove some common fixed point theorems for fuzzy contraction respect to a mapping, which satisfies a condition of weak compatibility. We deduce also fixed point results for fuzzy contractive mappings in the sense of Gregori and Sapena.

Discrete mathematicsFuzzy metric spaceGeneral MathematicsFixed pointFixed-point propertyFuzzy logicFuzzy metric spaceLeast fixed pointPoints of coincidenceCommon fixed pointSettore MAT/05 - Analisi MatematicaFixed-point iterationCommon fixed pointDiscontinuous mappingCoincidence pointMathematicsRendiconti del Circolo Matematico di Palermo
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Fixed point results for F-contractive mappings of Hardy-Rogers-type

2014

Recently, Wardowski introduced a new concept of contraction and proved a fixed point theorem which generalizes Banach contraction principle. Following this direction of research, in this paper, we will present some fixed point results of Hardy-Rogers-type for self-mappings on complete metric spaces or complete ordered metric spaces. Moreover, an example is given to illustrate the usability of the obtained results.

Discrete mathematicsGeneral MathematicsInjective metric spaceMetric spaces ordered metric spaces fixed points F-contractions of Hardy-Rogers-typeFixed-point theoremFixed pointFixed-point propertyConvex metric spaceUniform continuitySettore MAT/05 - Analisi MatematicaFréchet spaceContraction mappingMathematicsFilomat
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Characterizing extreme points of polyhedra an extension of a result by Wolfgang Bühler

1982

This paper reconsiders the characterization given by Buhler admitting convex polyhedra of probability distributions on a finite or countable set which are given by systems of linear inequalities more complex than those considered before.

Discrete mathematicsGeneral MathematicsRegular polygonInteger points in convex polyhedraManagement Science and Operations ResearchCombinatoricsPolyhedronLinear inequalityConvex polytopeCountable setExtreme pointSoftwareSpherical polyhedronMathematicsZeitschrift für Operations Research
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Fixed point and homotopy results for mixed multi-valued mappings in 0-complete partial metric spaces*

2015

We give sufficient conditions for the existence of common fixed points for a pair of mixed multi-valued mappings in the setting of 0-complete partial metric spaces. An example is given to demonstrate the usefulness of our results over the existing results in metric spaces. Finally, we prove a homotopy theorem via fixed point results.

Discrete mathematicsHomotopy categoryPartial metric spacefixed pointsApplied MathematicsInjective metric spacepartial metric spaceslcsh:QA299.6-433multi-valued mappingslcsh:AnalysisFixed pointFixed-point propertyIntrinsic metricConvex metric spacen-connectedMetric spaceSettore MAT/05 - Analisi Matematicamulti-valued mappingMetric (mathematics)AnalysisMathematics
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Common fixed points for self-mappings on partial metric spaces

2012

Abstract In this paper, we prove some results of a common fixed point for two self-mappings on partial metric spaces. Our results generalize some interesting results of Ilić et al. (Appl. Math. Lett. 24:1326-1330, 2011). We conclude with a result of the existence of a fixed point for set-valued mappings in the context of 0-complete partial metric spaces. MSC:54H25, 47H10.

Discrete mathematicsInjective metric spaceApplied Mathematics010102 general mathematicsEquivalence of metricscommon fixed point01 natural sciencesConvex metric spaceIntrinsic metric010101 applied mathematicsMetric spacepoints of coincidence0-complete partial metric spaceSettore MAT/05 - Analisi Matematicaψ-contractions.Metric (mathematics)Metric mapGeometry and Topology0101 mathematicsCoincidence pointMathematicsFixed Point Theory and Applications
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Uniformly nonsquare Banach spaces have the fixed point property for nonexpansive mappings

2006

Abstract It is shown that if the modulus Γ X of nearly uniform smoothness of a reflexive Banach space satisfies Γ X ′ ( 0 ) 1 , then every bounded closed convex subset of X has the fixed point property for nonexpansive mappings. In particular, uniformly nonsquare Banach spaces have this property since they are properly included in this class of spaces. This answers a long-standing question in the theory.

Discrete mathematicsMathematics::Functional AnalysisPure mathematicsUniformly nonsquare spacesApproximation propertyEberlein–Šmulian theoremBanach spaceNonexpansive mappingsUniformly convex spaceBanach manifoldFixed-point propertyNearly uniform smoothnessFixed pointsReflexive spaceLp spaceAnalysisMathematicsJournal of Functional Analysis
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Suzukiʼs type characterizations of completeness for partial metric spaces and fixed points for partially ordered metric spaces

2012

Abstract Recently, Suzuki [T. Suzuki, A generalized Banach contraction principle that characterizes metric completeness, Proc. Amer. Math. Soc. 136 (2008) 1861–1869] proved a fixed point theorem that is a generalization of the Banach contraction principle and characterizes the metric completeness. In this paper we prove an analogous fixed point result for a self-mapping on a partial metric space or on a partially ordered metric space. Our results on partially ordered metric spaces generalize and extend some recent results of Ran and Reurings [A.C.M. Ran, M.C. Reurings, A fixed point theorem in partially ordered sets and some applications to matrix equations, Proc. Amer. Math. Soc. 132 (2004…

Discrete mathematicsPartial metric spacesPartially ordered metric spacesInjective metric spaceMathematics::General TopologyPartial metric completenessEquivalence of metricsFixed-point propertyFixed points Common fixed points Partial metric spaces Partially ordered metric spaces Partial metric completenessConvex metric spaceIntrinsic metricLeast fixed pointFixed pointsMetric spaceSettore MAT/05 - Analisi MatematicaCommon fixed pointsGeometry and TopologyMetric differentialMathematicsTopology and its Applications
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