A documentation generator for logic programming systems

We describe lpdoc, a tool which generates documentation manuals automatically from one or more logic program source files, written in ISO-Prolog, Ciao, and other (C)LP languages. It is particularly useful for documenting library modules, for which it automatically generates a rich description of the module interface. However, it can also be used quite successfully to document full applications. The documentation can be generated in many formats including t e x i n f o, dvi, ps, pdf, inf o, html/css, Unix nrof f/man, Windows help, etc., and can include bibliographic citations and images, lpdoc can also genérate "man" pages (Unix man page format), nicely formatted plain ascii "readme" files, installation scripts useful when the manuals are included in software distributions, brief descriptions in html/css or inf o formats suitable for inclusión in on-line Índices of manuals, and even complete WWW and inf o sites containing on-line catalogs of documents and software distributions. A fundamental advantage of using lpdoc is that it helps maintaining a true correspondence between the program and its documentation, and also identifying precisely to what versión of the program a given printed manual corresponds. The quality of the documentation generated can be greatly enhanced by including within the program text assertions (declarations with types, modes, etc. ...) for the predicates in the program, and machine-readable comments. These assertions and comments are written using the Ciao system assertion language. A simple compatibility library allows conventional (C)LP systems to ignore these assertions and comments and treat normally programs documented in this way. The lpdoc manual, all other Ciao system manuals, and most of this paper, are generated by lpdoc.

An assertion language for debugging of constraint logic programs

Abstract is not available.

Towards dynamic term size computation via program transformation

Knowing the size of the terms to which program variables are bound at run-time in logic programs is required in a class of applications related to program optimization such as, for example, recursion elimination and granularity analysis. Such size is difficult to even approximate at compile time and is thus generally computed at run-time by using (possibly predefined) predicates which traverse the terms involved. We propose a technique based on program transformation which has the potential of performing this computation much more efficiently. The technique is based on finding program procedures which are called before those in which knowledge regarding term sizes is needed and which traverse the terms whose size is to be determined, and transforming such procedures so that they compute term sizes "on the fly". We present a systematic way of determining whether a given program can be transformed in order to compute a given term size at a given program point without additional term traversal. Also, if several such transformations are possible our approach allows finding minimal transformations under certain criteria. We also discuss the advantages and present some applications of our technique.

An overview of ciao and its design philosophy

We provide an overall description of the Ciao multiparadigm programming system emphasizing some of the novel aspects and motivations behind its design and implementation. An important aspect of Ciao is that, in addition to supporting logic programming (and, in particular, Prolog), it provides the programmer with a large number of useful features from different programming paradigms and styles and that the use of each of these features (including those of Prolog) can be turned on and off at will for each program module. Thus, a given module may be using, e.g., higher order functions and constraints, while another module may be using assignment, predicates, Prolog meta-programming, and concurrency. Furthermore, the language is designed to be extensible in a simple and modular way. Another important aspect of Ciao is its programming environment, which provides a powerful preprocessor (with an associated assertion language) capable of statically finding non-trivial bugs, verifying that programs comply with specifications, and performing many types of optimizations (including automatic parallelization). Such optimizations produce code that is highly competitive with other dynamic languages or, with the (experimental) optimizing compiler, even that of static languages, all while retaining the flexibility and interactive development of a dynamic language. This compilation architecture supports modularity and separate compilation throughout. The environment also includes a powerful autodocumenter and a unit testing framework, both closely integrated with the assertion system. The paper provides an informal overview of the language and program development environment. It aims at illustrating the design philosophy rather than at being exhaustive, which would be impossible in a single journal paper, pointing instead to previous Ciao literature.

The ciao prolog system

Ciao is a public domain, next generation multi-paradigm programming environment with a unique set of features: Ciao offers a complete Prolog system, supporting ISO-Prolog, but its novel modular design allows both restricting and extending the language. As a result, it allows working with fully declarative subsets of Prolog and also to extend these subsets (or ISO-Prolog) both syntactically and semantically. Most importantly, these restrictions and extensions can be activated separately on each program module so that several extensions can coexist in the same application for different modules. Ciao also supports (through such extensions) programming with functions, higher-order (with predicate abstractions), constraints, and objects, as well as feature terms (records), persistence, several control rules (breadth-first search, iterative deepening, ...), concurrency (threads/engines), a good base for distributed execution (agents), and parallel execution. Libraries also support WWW programming, sockets, external interfaces (C, Java, TclTk, relational databases, etc.), etc. Ciao offers support for programming in the large with a robust module/object system, module-based separate/incremental compilation (automatically -no need for makefiles), an assertion language for declaring (optional) program properties (including types and modes, but also determinacy, non-failure, cost, etc.), automatic static inference and static/dynamic checking of such assertions, etc. Ciao also offers support for programming in the small producing small executables (including only those builtins used by the program) and support for writing scripts in Prolog. The Ciao programming environment includes a classical top-level and a rich emacs interface with an embeddable source-level debugger and a number of execution visualization tools. The Ciao compiler (which can be run outside the top level shell) generates several forms of architecture-independent and stand-alone executables, which run with speed, efficiency and executable size which are very competive with other commercial and academic Prolog/CLP systems. Library modules can be compiled into compact bytecode or C source files, and linked statically, dynamically, or autoloaded. The novel modular design of Ciao enables, in addition to modular program development, effective global program analysis and static debugging and optimization via source to source program transformation. These tasks are performed by the Ciao preprocessor ( ciaopp, distributed separately). The Ciao programming environment also includes lpdoc, an automatic documentation generator for LP/CLP programs. It processes Prolog files adorned with (Ciao) assertions and machine-readable comments and generates manuals in many formats including postscript, pdf, texinfo, info, HTML, man, etc. , as well as on-line help, ascii README files, entries for indices of manuals (info, WWW, ...), and maintains WWW distribution sites.

O'CIAO an object oriented programming model using CIAO Prolog

There have been several previous proposals for the integration of Object Oriented Programming features into Logic Programming, resulting in much support theory and several language proposals. However, none of these proposals seem to have made it into the mainstream. Perhaps one of the reasons for these is that the resulting languages depart too much from the standard logic programming languages to entice the average Prolog programmer. Another reason may be that most of what can be done with object-oriented programming can already be done in Prolog through the meta- and higher-order programming facilities that the language includes, albeit sometimes in a more cumbersome way. In light of this, in this paper we propose an alternative solution which is driven by two main objectives. The first one is to include only those characteristics of object-oriented programming which are cumbersome to implement in standard Prolog systems. The second one is to do this in such a way that there is minimum impact on the syntax and complexity of the language, i.e., to introduce the minimum number of new constructs, declarations, and concepts to be learned. Finally, we would like the implementation to be as straightforward as possible, ideally based on simple source to source expansions.

Optimization of logic programs with dynamic scheduling

Dynamic scheduling increases the expressive power of logic programming languages, but also introduces some overhead. In this paper we present two classes of program transformations designed to reduce this additional overhead, while preserving the operational semantics of the original programs, modulo ordering of literals woken at the same time. The first class of transformations simplifies the delay conditions while the second class moves delayed literals later in the rule body. Application of the program transformations can be automated using information provided by compile-time analysis. We provide experimental results obtained from an implementation of the proposed techniques using the CIAO prototype compiler. Our results show that the techniques can lead to substantial performance improvement.

Automatic compile-time parallelization of CLP programs by analysis and transformation to a concurrent constraint language.

The concept of independence has been recently generalized to the constraint logic programming (CLP) paradigm. Also, several abstract domains specifically designed for CLP languages, and whose information can be used to detect the generalized independence conditions, have been recently defined. As a result we are now in a position where automatic parallelization of CLP programs is feasible. In this paper we study the task of automatically parallelizing CLP programs based on such analyses, by transforming them to explicitly concurrent programs in our parallel CC platform (CIAO) as well as to AKL. We describe the analysis and transformation process, and study its efficiency, accuracy, and effectiveness in program parallelization. The information gathered by the analyzers is evaluated not only in terms of its accuracy, i.e. its ability to determine the actual dependencies among the program variables, but also of its effectiveness, measured in terms of code reduction in the resulting parallelized programs. Given that only a few abstract domains have been already defined for CLP, and that none of them were specifically designed for dependency detection, the aim of the evaluation is not only to asses the effectiveness of the available domains, but also to study what additional information it would be desirable to infer, and what domains would be appropriate for further improving the parallelization process.

Programming assignments automatic grading: review of tools and implementations

Automatic grading of programming assignments is an important topic in academic research. It aims at improving the level of feedback given to students and optimizing the professor time. Several researches have reported the development of software tools to support this process. Then, it is helpfulto get a quickly and good sight about their key features. This paper reviews an ample set of tools forautomatic grading of programming assignments. They are divided in those most important mature tools, which have remarkable features; and those built recently, with new features. The review includes the definition and description of key features e.g. supported languages, used technology, infrastructure, etc. The two kinds of tools allow making a temporal comparative analysis. This analysis infrastructure, etc. The two kinds of tools allow making a temporal comparative analysis. This analysis shows good improvements in this research field, these include security, more language support, plagiarism detection, etc. On the other hand, the lack of a grading model for assignments is identified as an important gap in the reviewed tools. Thus, a characterization of evaluation metrics to grade programming assignments is provided as first step to get a model. Finally new paths in this research field are proposed.

Towards the automatic generation of card games through Grammar-Guided Genetic Programming

We demonstrate generating complete and playable card games using evolutionary algorithms. Card games are represented in a previously devised card game description language, a context-free grammar. The syntax of this language allows us to use grammar-guided genetic programming. Candidate card games are evaluated through a cascading evaluation function, a multi-step process where games with undesired properties are progressively weeded out. Three representa- tive examples of generated games are analysed. We observed that these games are reasonably balanced and have skill ele- ments, they are not yet entertaining for human players. The particular shortcomings of the examples are discussed in re- gard to the generative process to be able to generate quality games

DCE@urLAB: a dynamic contrast-enhanced MRI pharmacokinetic analysis tool for preclinical data

Background DCE@urLAB is a software application for analysis of dynamic contrast-enhanced magnetic resonance imaging data (DCE-MRI). The tool incorporates a friendly graphical user interface (GUI) to interactively select and analyze a region of interest (ROI) within the image set, taking into account the tissue concentration of the contrast agent (CA) and its effect on pixel intensity. Results Pixel-wise model-based quantitative parameters are estimated by fitting DCE-MRI data to several pharmacokinetic models using the Levenberg-Marquardt algorithm (LMA). DCE@urLAB also includes the semi-quantitative parametric and heuristic analysis approaches commonly used in practice. This software application has been programmed in the Interactive Data Language (IDL) and tested both with publicly available simulated data and preclinical studies from tumor-bearing mouse brains. Conclusions A user-friendly solution for applying pharmacokinetic and non-quantitative analysis DCE-MRI in preclinical studies has been implemented and tested. The proposed tool has been specially designed for easy selection of multi-pixel ROIs. A public release of DCE@urLAB, together with the open source code and sample datasets, is available at http://www.die.upm.es/im/archives/DCEurLAB/ webcite.

Manejo de memoria en programación lógica con tabulación

Los lenguajes de programación son el idioma que los programadores usamos para comunicar a los computadores qué queremos que hagan. Desde el lenguaje ensamblador, que traduce una a una las instrucciones que interpreta un computador hasta lenguajes de alto nivel, se ha buscado desarrollar lenguajes más cercanos a la forma de pensar y expresarse de los humanos. Los lenguajes de programación lógicos como Prolog utilizan a su vez el lenguaje de la lógica de 1er orden de modo que el programador puede expresar las premisas del problema que se quiere resolver sin preocuparse del cómo se va a resolver dicho problema. La resolución del problema se equipara a encontrar una deducción del objetivo a alcanzar a partir de las premisas y equivale a lo que entendemos por la ejecución de un programa. Ciao es una implementación de Prolog (http://www.ciao-lang.org) y utiliza el método de resolución SLD, que realiza el recorrido de los árboles de decisión en profundidad(depth-first) lo que puede derivar en la ejecución de una rama de busqueda infinita (en un bucle infinito) sin llegar a dar respuestas. Ciao, al ser un sistema modular, permite la utilización de extensiones para implementar estrategias de resolución alternativas como la tabulación (OLDT). La tabulación es un método alternativo que se basa en memorizar las llamadas realizadas y sus respuestas para no repetir llamadas y poder usar las respuestas sin recomputar las llamadas. Algunos programas que con SLD entran en un bucle infinito, gracias a la tabulación dán todas las respuestas y termina. El modulo tabling es una implementación de tabulación mediante el algoritmo CHAT. Esta implementación es una versión beta que no tiene implementado un manejador de memoria. Entendemos que la gestión de memoria en el módulo de tabling tiene gran importancia, dado que la resolución con tabulación permite reducir el tiempo de computación (al no repetir llamadas), aumentando los requerimientos de memoria (para guardar las llamadas y las respuestas). Por lo tanto, el objetivo de este trabajo es implementar un mecanismo de gestión de la memoria en Ciao con el módulo tabling cargado. Para ello se ha realizado la implementación de: Un mecanismo de captura de errores que: detecta cuando el computador se queda sin memoria y activa la reinicialización del sitema. Un procedimiento que ajusta los punteros del modulo de tabling que apuntan a la WAM tras un proceso de realojo de algunas de las áreas de memoria de la WAM. Un gestor de memoria del modulo de tabling que detecta c realizar una ampliación de las áreas de memoria del modulo de tabling, realiza la solicitud de más memoria y realiza el ajuste de los punteros. Para ayudar al lector no familiarizado con este tema, describimos los datos que Ciao y el módulo de tabling alojan en las áreas de memoria dinámicas que queremos gestionar. Los casos de pruebas desarrollados para evaluar la implementación del gestor de memoria, ponen de manifiesto que: Disponer de un gestor de memoria dinámica permite la ejecución de programas en un mayor número de casos. La política de gestión de memoria incide en la velocidad de ejecución de los programas. ---ABSTRACT---Programming languages are the language that programmers use in order to communicate to computers what we want them to do. Starting from the assembly language, which translates one by one the instructions to the computer, and arriving to highly complex languages, programmers have tried to develop programming languages that resemble more closely the way of thinking and communicating of human beings. Logical programming languages, such as Prolog, use the language of logic of the first order so that programmers can express the premise of the problem that they want to solve without having to solve the problem itself. The solution to the problem is equal to finding a deduction of the objective to reach starting from the premises and corresponds to what is usually meant as the execution of a program. Ciao is an implementation of Prolog (http://www.ciao-lang.org) and uses the method of resolution SLD that carries out the path of the decision trees in depth (depth-frist). This can cause the execution of an infinite searching branch (an infinite loop) without getting to an answer. Since Ciao is a modular system, it allows the use of extensions to implement alternative resolution strategies, such as tabulation (OLDT). Tabulation is an alternative method that is based on the memorization of executions and their answers, in order to avoid the repetition of executions and to be able to use the answers without reexecutions. Some programs that get into an infinite loop with SLD are able to give all the answers and to finish thanks to tabulation. The tabling package is an implementation of tabulation through the algorithm CHAT. This implementation is a beta version which does not present a memory handler. The management of memory in the tabling package is highly important, since the solution with tabulation allows to reduce the system time (because it does not repeat executions) and increases the memory requirements (in order to save executions and answers). Therefore, the objective of this work is to implement a memory management mechanism in Ciao with the tabling package loaded. To achieve this goal, the following implementation were made: An error detection system that reveals when the computer is left without memory and activate the reinizialitation of the system. A procedure that adjusts the pointers of the tabling package which points to the WAM after a process of realloc of some of the WAM memory stacks. A memory manager of the tabling package that detects when it is necessary to expand the memory stacks of the tabling package, requests more memory, and adjusts the pointers. In order to help the readers who are not familiar with this topic, we described the data which Ciao and the tabling package host in the dynamic memory stacks that we want to manage. The test cases developed to evaluate the implementation of the memory manager show that: A manager for the dynamic memory allows the execution of programs in a larger number of cases. Memory management policy influences the program execution speed.

Dynamic analysis of translational shells

This paper presents a Levy-type solution for the natural frequencies of translational shells. A computer program in FORTRAN IV language corresponding to this solution is described. This direct solution is compared with some indirect solutions utilising Galerkin and Rayleigh methods. An extension to the study of forced vibrations is outlined.

Mobile assisted language learning : prototipo de la aplicación UP2B2

La forma de consumir contenidos en Internet ha cambiado durante los últimos años. Inicialmente se empleaban webs estáticas y con contenidos pobres visualmente. Con la evolución de las redes de comunicación, esta tendencia ha variado. A día de hoy, deseamos páginas agradables, accesibles y que nos presenten temas variados. Todo esto ha cambiado la forma de crear páginas web y en todos los casos se persigue el objetivo de atraer a los usuarios. El gran auge de los smartphones y las aplicaciones móviles que invaden el mercado actual han revolucionado el mundo del estudio de los idiomas permitiendo compatibilizar los recursos punteros con el aprendizaje tradicional. La popularidad de los dispositivos móviles y de las aplicaciones ha sido el principal motivo de la realización de este proyecto. En él se realizará un análisis de las diferentes tecnologías existentes y se elegirá la mejor opción que se ajuste a nuestras necesidades para poder desarrollar un sistema que implemente el enfoque llamado Mobile Assisted Language Learning (MALL) que supone una aproximación innovadora al aprendizaje de idiomas con la ayuda de un dispositivo móvil. En este documento se va a ofrecer una panorámica general acerca del desarrollo de aplicaciones para dispositivos móviles en el entorno del e-learning. Se estudiarán características técnicas de diferentes plataformas seleccionando la mejor opción para la implementación de un sistema que proporcione los contenidos básicos para el aprendizaje de un idioma, en este caso del inglés, de forma intuitiva y divertida. Dicho sistema permitirá al usuario mejorar su nivel de inglés mediante una interfaz web de forma dinámica y cercana empleando los recursos que ofrecen los dispositivos móviles y haciendo uso del diseño adaptativo. Este proyecto está pensado para los usuarios que dispongan de poco tiempo libre para realizar un curso de forma presencial o, mejor aún, para reforzar o repasar contenidos ya aprendidos por otros medios más tradicionales o no. La aplicación ofrece la posibilidad de que se haga uso del sistema de forma fácil y sencilla desde cualquier dispositivo móvil del que se disponga como es un smartphone, tablet o un ordenador personal, compitiendo con otros usuarios o contra uno mismo y mejorando así el nivel de partida a través de las actividades propuestas. Durante el proyecto se han comparado diversas soluciones, la mayoría de código abierto y de libre distribución que permiten desplegar servicios de almacenamiento accesibles mediante Internet. Se concluirá con un caso práctico analizando los requisitos técnicos y llevando a cabo las fases de análisis, diseño, creación de la base de datos, implementación y pruebas dentro del ciclo de vida del software. Finalmente, se migrará la aplicación con toda la información a un servidor en la nube. ABSTRACT. The way of consuming content on the Internet has changed over the past years. Initially, static websites were used with poor visual contents. Nevertheless, with the evolution of communication networks this trend has changed. Nowadays, we expect pleasant, accessible and varied topic pages and such expectations have changed the way to create web pages generally aiming at appealing and therefore, attracting users. The great boom of smartphones and mobile applications in the current market, have revolutionized the world of language learning as they make it possible to combine computing with traditional learning resources. The popularity of mobile devices and applications has been the main reason for the development of this project. Here, the different existing technologies will be examined and we will try to select the best option that adapts to our needs in order to develop a system that implements Mobile Assisted Language Learning (MALL) that in broad terms implies an approach to language learning with the help of a mobile device. This report provides an overview of the development of applications for mobile devices in the e-learning environment. We will study the technical characteristics of different platforms and we will select the best option for the implementation of a system that provide the basic content for learning a language, in this case English, by means of an intuitive and fun method. This system will allow the user to improve their level of English with a web interface in a dynamic and close way employing the resources offered by mobile devices using the adaptive design. This project is intended for users who do not have enough free time to make a classroom course or to review contents from more traditional courses as it offers the possibility to make use of the system quickly and easily from any mobile device available such as a smartphone, a tablet or a personal computer, competing with other users or against oneself and thus improving their departing level through different activities. During the project, different solutions have been compared. Most of them, open source and free distribution that allow to deploy storage services accessible via the Internet. It will conclude with a case study analyzing the technical requirements and conducting phases of analysis, design and creation of a database, implementation and testing in the software lifecycle. Finally, the application will be migrated with all the information to a server in the cloud.

Programación en lenguaje Java de algoritmo Zig-Zag para procesado de archivos MIDI

El siguiente proyecto versa sobre la programación en lenguaje java del algoritmo de humanización MIDI desarrollado por Jorge Grundman en su tesis La Humanización de la Interpretación Virtual: Tres ejemplos significativos de la obra de Chopin. Este algoritmo, denominado Zig-Zag tiene como finalidad lograr que una partitura interpretada por un ordenador tenga unas características similares a la lectura a primera vista de la misma por un pianista. Para ello, basa su funcionamiento en una aleatorización del tempo en base a una serie de parámetros, a una modificación de la dinámica acorde a la modificación de tempo y a una segunda aleatorización para cada figura de la partitura. Este algoritmo tiene un gran campo de aplicación como complemento a los diversos secuenciadores y editores de partituras que existen en la actualidad, proporcionando nuevas características a los mismos. La programación del algoritmo se ha llevado a cabo empleando el Java SDK (Standard Developement Kit) 7 y las herramientas que proporciona esta plataforma para el manejo y modificación de los mensajes MIDI. ABSTRACT. The next project is about the programming in Java language of the MIDI humanization algorithm developed by Jorge Grundman in his thesis La Humanización de la Interpretación Virtual: Tres ejemplos significativos de la obra de Chopin. This algorithm, called Zig-Zag aims to have similar characteristics in a score performed by a computer than in the sight reading by a pianist. To this end, it bases its process in a randomization of the tempo from several parameters, a modification of the dynamic according to the change of tempo and a second randomization for each figure in the score. This algorithm has a big scope of application as complement for the different sequencers and score editors that already exist, providing new features to them. The algorithm has been programmed using the Java SDK (Standard Development Kit) 7 and the tools that this platform provides to handle and modify MIDI messages.