37 research outputs found

    Compiling a simulation language in APL

    Full text link
    This is the author's version of the work. It is posted here for your personal use. Not for redistribution. The definitive Version of Record was published in APL Quote Quad, http://dx.doi.org/10.1145/327600.327625This paper describes the procedure used to build several compilers, written in APL and APL2, to translate two continuous simulation languages into APL and C++. The advantages and disadvantages of using APL to write a compiler are discussed. A compromise had to be found between performance (the model execution speed) and flexibility (the ease to modify parameters and test "what if" situations). The resulting compiler (an APL2 packaged workspace) has been used successfully to generate educational applications and in medical research.This paper has been sponsored by the Spanish Interdepartmental Commission of Science and Technology (CICYT), project number TIC-96-0723-C02-01

    The Split-Apply-Combine Strategy for Data Analysis

    Get PDF
    Many data analysis problems involve the application of a split-apply-combine strategy, where you break up a big problem into manageable pieces, operate on each piece independently and then put all the pieces back together. This insight gives rise to a new R package that allows you to smoothly apply this strategy, without having to worry about the type of structure in which your data is stored. The paper includes two case studies showing how these insights make it easier to work with batting records for veteran baseball players and a large 3d array of spatio-temporal ozone measurements.

    JMSL - a language derived from APL

    Get PDF
    A new AFL-derived language called JMSL is presented which rnodifies seven aspects of APL so that many current and potential APL users could benefit from a language which is easier to learn, read, write, and maintain. JMSL uses ASCII tokens instead of APL symbols to remedy interfacing, extensibility, and readability problems with APL. JMSL revises and extends APL built-in capabilities to provide greater expression and improved symbol-meaning correspondence. JMSL includes a new notation for nested arrays (a powerful data structure which combines the array processing of APL with the tree processing of LISP). JMSL provides hierarchical directories (similar to PASCAL or PL/I records) to allow structures to be indexed by name. JMSL modifies the traditional APL library/workspace storage interface by unifying the syntax of system commands in a way which allows UNIX-like directory storage. JMSL provides high-level control structures similar to those found in block-structured languages, including an event-handling mechanism. JMSL amends the APL scope rules to alleviate problems with side effects and object localization. Some areas of future work are discussed, and a description of JMSL syntax and semantics is included

    The Split-Apply-Combine Strategy for Data Analysis

    Get PDF
    Many data analysis problems involve the application of a split-apply-combine strategy, where you break up a big problem into manageable pieces, operate on each piece independently and then put all the pieces back together. This insight gives rise to a new R package that allows you to smoothly apply this strategy, without having to worry about the type of structure in which your data is stored. The paper includes two case studies showing how these insights make it easier to work with batting records for veteran baseball players and a large 3d array of spatio-temporal ozone measurements

    Robotic workcell analysis and object level programming

    Get PDF
    For many years robots have been programmed at manipulator or joint level without any real thought to the implementation of sensing until errors occur during program execution. For the control of complex, or multiple robot workcells, programming must be carried out at a higher level, taking into account the possibility of error occurrence. This requires the integration of decision information based on sensory data.Aspects of robotic workcell control are explored during this work with the object of integrating the results of sensor outputs to facilitate error recovery for the purposes of achieving completely autonomous operation.Network theory is used for the development of analysis techniques based on stochastic data. Object level programming is implemented using Markov chain theory to provide fully sensor integrated robot workcell control

    Digital Alchemy: Matter and Metamorphosis in Contemporary Digital Animation and Interface Design

    Get PDF
    The recent proliferation of special effects in Hollywood film has ushered in an era of digital transformation. Among scholars, digital technology is hailed as a revolutionary moment in the history of communication and representation. Nevertheless, media scholars and cultural historians have difficulty finding a language adequate to theorizing digital artifacts because they are not just texts to be deciphered. Rather, digital media artifacts also invite critiques about the status of reality because they resurrect ancient problems of embodiment and transcendence.In contrast to scholarly approaches to digital technology, computer engineers, interface designers, and special effects producers have invented a robust set of terms and phrases to describe the practice of digital animation. In order to address this disconnect between producers of new media and scholars of new media, I argue that the process of digital animation borrows extensively from a set of preexisting terms describing materiality that were prominent for centuries prior to the scientific revolution. Specifically, digital animators and interface designers make use of the ancient science, art, and technological craft of alchemy. Both alchemy and digital animation share several fundamental elements: both boast the power of being able to transform one material, substance, or thing into a different material, substance, or thing. Both seek to transcend the body and materiality but in the process, find that this elusive goal (realism and gold) is forever receding onto the horizon.The introduction begins with a literature review of the field of digital media studies. It identifies a gap in the field concerning disparate arguments about new media technology. On the one hand, scholars argue that new technologies like cyberspace and digital technology enable radical new forms of engagement with media on individual, social, and economic levels. At the same time that media scholars assert that our current epoch is marked by a historical rupture, many other researchers claim that new media are increasingly characterized by ancient metaphysical problems like embodiment and transcendence. In subsequent chapters I investigate this disparity

    NASA Tech Briefs, February 1994

    Get PDF
    Topics covered include: Test and Measurement; Electronic Components and Circuits; Electronic Systems; Physical Sciences; Materials; Computer Programs; Mechanics; Machinery; Fabrication Technology; Mathematics and Information Sciences; Life Sciences; Books and Report

    Interactive graphics, graphical user interfaces and software interfaces for the analysis of biological experimental data and networks

    Get PDF
    Biologists need to analyze and comprehend increasingly large and more complex multivariate experimental data. Biological experiments often produce multiple data sets, each describing one aspect of the system, such as the transcriptome recorded by a microarray or metabolome recorded using gas chromatography mass spectrometry (GC-MS). A biochemical network model provides a conceptual system-level framework for integrating data from different sources.;Effective use of graphics enhances the comprehension of data, and interactive graphics permit the analyst to actively explore data, check its integrity, satiate curiosities and reveal the unexpected. Interactive graphics have not been widely applied as a means for understanding data from biological experiments.;This thesis addresses these needs by providing new methods and software that apply interactive graphics in coordination with numerical methods to the analysis of biological data, in a manner that is accessible to biologists
    corecore