Reseña: Formalization of real analysis: A survey of proof assistants and libraries

Se ha publicado un artículo sobre razonamiento formalizado titudado Formalization of real analysis: A survey of proof assistants and libraries.

Sus autores son Sylvie Boldo, Catherine Lelay y Guillaume Melquiond.

Su resumen es

In the recent years, numerous proof systems have improved enough to be used for formally verifying non-trivial mathematical results. They, however, have different purposes and it is not always easy to choose which one is adapted to undertake a formalization effort. In this survey, we focus on properties related to real analysis: real numbers, arithmetic operators, limits, differentiability, integrability, and so on. We have chosen to look into the formalizations provided in standard by the following systems: Coq, HOL4, HOL Light, Isabelle/HOL, Mizar, ProofPower-HOL, and PVS. We have also accounted for large developments that play a similar role or extend standard libraries: ACL2(r) for ACL2, C-CoRN/MathClasses for Coq, and the NASA PVS library. This survey presents how real numbers have been defined in these various provers and how the notions of real analysis described above have been formalized. We also look at the proof automations these systems provide for real analysis.

I1M2012: El TAD de los polinomios en Haskell (2)

En la clase de hoy de Informática de 1º del Grado en Matemáticas hemos continuado el estudio del tipo abstracto de los polinomios y su implementación en Haskell que comenzamos en la clase anterior. Concretamente, hemos estudiado la implementaciones en Haskell del TAD de los polinomios mediante listas densas y las operaciones con los polinomios usando el TAD.

Las transparencias usadas en la clase son las páginas 24-55 del tema 21
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Reseña: Data refinement in Isabelle/HOL

Se ha publicado un artículo sobre automatización del razonamiento en Isabelle/HOL titulado Data refinement in Isabelle/HOL.

Sus autores son Florian Haftmann, Alexander Krauss, Ondřej Kunčar y Tobias Nipkow (de la Universidad Técnica de Munich).

El trabajo se presentará en julio en el ITP 2013 (4th Conference on
Interactive Theorem Proving).

Su resumen es

The paper shows how the code generator of Isabelle/HOL supports data refinement, i.e., providing efficient code for operations on abstract types, e.g., sets or numbers. This allows all tools that employ code generation, e.g., Quickcheck or proof by evaluation, to compute with these abstract types. At the core is an extension of the code generator to deal with data type invariants. In order to automate the process of setting up specific data refinements, two packages for transferring definitions and theorems between types are exploited.

Reseña: Homotopy limits in Coq

Se ha publicado un artículo de razonamiento formalizado en Coq titulado Homotopy limits in Coq.

Sus autores son Jeremy Avigad (de la Carnegie Mellon University), Krzysztof Kapulkin (de la Univ. de Pittsburgh) y Peter LeFanu Lumsdaine.

Su resumen es

Working in Homotopy Type Theory, we provide a systematic study of basic homotopy limits and related constructions. The entire development has been formally verified in the Coq interactive proof assistant.

Las teorías en Coq correspondientes al artículo se encuentra aquí.