Combinatorics on words | String (computer science)

Alternation (formal language theory)

In formal language theory and pattern matching, alternation is the union of two sets of strings, or equivalently the logical disjunction of two patterns describing sets of strings. Regular languages are closed under alternation, meaning that the alternation of two regular languages is again regular. In implementations of regular expressions, alternation is often expressed with a vertical bar connecting the expressions for the two languages whose union is to be matched, while in more theoretical studies the plus sign may instead be used for this purpose. The ability to construct finite automata for unions of two regular languages that are themselves defined by finite automata is central to the equivalence between regular languages defined by automata and by regular expressions. Other classes of languages that are closed under alternation include context-free languages and recursive languages.The vertical bar notation for alternation is used in the SNOBOL language and some other languages.In formal language theory, alternation is commutative and associative. This is not in general true of the form of alternation used in pattern-matching languages, because of the side-effects of performing a match in those languages. (Wikipedia).

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MOR106 - Morphological Alternation

One of the most common complications of simple morphological analysis is that morphemes may have different shapes under different circumstances. This phenomenon is referred to as morphological alternation. In this video, Prof. Dr. Handke and his robot-assistant, Pepper, discuss the central

From playlist VLC206 - Morphology and Syntax

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The Origin of Language

#i3G This Video is about the origins of language. It reviews two hypotheses among the several available theories. #homo sapiens #homo erectus #Neanderthals #Noam Chomsky #Ian Tattersall #Robert Berwick #Daniel Everette

From playlist What is Language?

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MOR106 - Morphological Alternation

One of the most common complications of simple morphological analysis is that morphemes may have different shapes under different circumstances. This phenomenon is referred to as morphological alternation. This clip discusses the main types of "allomorphy" as well as the central conditioni

From playlist VLC104 - Words and Word Structure

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SYN_018 - Linguistic Micro-Lectures: Recursion

In this short micro-lecture, Victoria Galarneau, one of Prof. Handke's students, discusses the term 'recursion', a central notion in syntax.

From playlist Micro-Lectures - Syntax

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SEM131 - Ambiguity

This E-Lecture discusses and exemplifies the phenomenon of ambiguity, ranging from lexical to pragmatic. And as usual, Prof. Handke uses numerous examples to illustrate this ubiquous property of natural language expressions.

From playlist VLC103 - The Nature of Meaning

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How is Language Built?| Intro to Human Communication | Study Hall

The way we choose and use words, whether it be speaking, writing, or signing, is shaped by language. Language is a system we use to express ideas by combining sounds, gestures, and symbols into words, phrases, and sentences. In this episode, we discuss how language evolves, the rules that

From playlist Intro to Human Communication: Course Foundations

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Homotopy Type Theory: what can logic do for homotopy theory? - Peter Lumsdaine

Peter Lumsdaine Homotopy Type Theory: what can logic do for homotopy theory? Institute for Advanced Study; Member, School of Mathematics October 4, 2013 For more videos, visit http://video.ias.edu

From playlist Mathematics

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Computer Science and Homotopy Theory - Vladimir Voevodsky

Vladimir Voevodsky Professor, School of Mathematics April 27, 2011 For more videos, visit http://video.ias.edu

From playlist Mathematics

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2. Python language semantics

Semantics and syntax are essentially the grammar rules that a programming language uses to make sure that information is communicated without misinterpretation. In coding, this is things like spelling, spacing, semicolons, brackets etc. This video covers a few of the key differences in pyt

From playlist Intro to Python Programming for Materials Engineers

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SYN110 - Variants of Generative Grammar I

There are several problems for simple phrase structure grammars (PSG). In this first E-Lecture of a series of related videos, Prof. Handke discusses these problems and points out where and what adjustments have to be made to expand a simple PSG into a more elaborate version of a generative

From playlist VLC107 - Syntax: Part II

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Inernal Languages for Higher Toposes - Michael Shulman

Michael Shulman University of California, San Diego; Member, School of Mathematics October 3, 2012 For more videos, visit http://video.ias.edu

From playlist Mathematics

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[Introduction to Linguistics] Word Creation

In this video, we look at Compounding, Clipping, Blending, Backformation, Acronyms, Initialisms, and Coinage as forms of word creation in English. LIKE AND SHARE THE VIDEO IF IT HELPED! Support me on Patreon: http://bit.ly/2EUdAl3 Visit our website: http://TrevTutor.com Subscribe on You

From playlist Introduction to Linguistics

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Live CEOing Ep 28: Proofs in the Wolfram Language

Watch Stephen Wolfram and teams of developers in a live, working, language design meeting. This episode is about Proofs in the Wolfram Language.

From playlist Behind the Scenes in Real-Life Software Design

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NLP at DARPA

Presented by: Eduard Hovy – Research Professor at the Language Technologies Institute at Carnegie Mellon University DARPA, the US Defense Advanced Research Projects Agency, has funded some portion of the development of almost every major NLP application, including machine translation, inf

From playlist NLP Summit 2021

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Logic: The Structure of Reason

As a tool for characterizing rational thought, logic cuts across many philosophical disciplines and lies at the core of mathematics and computer science. Drawing on Aristotle’s Organon, Russell’s Principia Mathematica, and other central works, this program tracks the evolution of logic, be

From playlist Logic & Philosophy of Mathematics

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Séminaire Bourbaki - 21/06/2014 - 3/4 - Thomas C. HALES

Developments in formal proofs A for mal proof is a proof that can be read and verified by computer, directly from the fundamental rules of logic and the foundational axioms of mathematics. The technology behind for mal proofs has been under development for decades and grew out of efforts i

From playlist Bourbaki - 21 juin 2014

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Nicolas Behr - Towards Executable Applied Category Theory in Coq

This talk will present the ”coreact.wiki” initiative, which aims to develop a novel form of wiki engine that will couple a database of human-readable mathematical knowledge with a database containing machine-readable and -executable representations of this knowledge in proof assistants suc

From playlist Combinatorics and Arithmetic for Physics: special days

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Language Change

In this module, Prof. Simon Horobin (University of Oxford) introduces the concept of semantic change, focusing in particular on the word 'literally'. As we move through the module, we consider: (i) the etymology of the word from the Latin 'littera' (letter), and the original meaning of the

From playlist English Language

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Live CEOing Ep 374: Language Design in Wolfram Language [AxiomaticTheory]

In this episode of Live CEOing, Stephen Wolfram discusses upcoming improvements of AxiomaticTheory for the Wolfram Language. If you'd like to contribute to the discussion in future episodes, you can participate through this YouTube channel or through the official Twitch channel of Stephen

From playlist Behind the Scenes in Real-Life Software Design

Related pages

Recursive language | Regular expression | Regular language | Union (set theory) | Context-free language | Formal language | Pattern matching | Logical disjunction