1 / 15

Scientific computing over the Web in various programming languages

Miguel Casquilho CERENA “Centre for Natural Resources and the Environment ” (CPQ) Department of Chemical Engineering Marco Cunha Dept. of Computer Science and Engineering IST Instituto Superior Técnico UL Universidade de Lisboa (University of Lisbon)

hinda
Download Presentation

Scientific computing over the Web in various programming languages

An Image/Link below is provided (as is) to download presentation Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author. Content is provided to you AS IS for your information and personal use only. Download presentation by click this link. While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server. During download, if you can't get a presentation, the file might be deleted by the publisher.

E N D

Presentation Transcript

  1. Miguel Casquilho CERENA“Centre for Natural Resources and the Environment” (CPQ) Department of Chemical Engineering Marco Cunha Dept. of Computer Science and Engineering ISTInstituto Superior Técnico UL Universidade de Lisboa(University of Lisbon) http://web.tecnico.ulisboa.pt/mcasquilho/ Scientific computing over the Webin various programming languages Scientific computing over the Web

  2. Scientific computing over the Webin variousprogramminglanguages: solving problems in Fortran, C, and Octave Abstract   Scientific computing over the Web (no installations) is shown with classical(Fortran 90, C) and modern (Octave) languages, to solve two numerical problems (having surprising results): a certain simple series, and the distance to random points in a circle. Our objective is twofold: (i) to emphasize the pertinence of the Web for scientific computing, and (ii) to comment the productiveness of the modern languages. Thefollowingpoints are addressed: Scientificcomputing: twoillustrativeproblems Solvingproblems in Fortran, C, andOctave Conclusions Fromtheauthors’ experience, theWeb environmentisrecommendedfor scientificcomputing for: academicand industrial purposes, andtheacademy-industryconnection. Scientific computing over the Web

  3. Scientific computing: two illustrative problems Solving problems in Fortran, C, and Octave Conclusions Scientific computing over the Webin variousprogramminglanguages Ernesto Halffter (1905–1989) Lisboa 1938–1954 Scientific computing over the Web

  4. 1.2. 3. Scientific computing: two illustrative problems • Problem 1) Suppose the following relation: • or simply • Let, e.g., n= 106: • This reminds of ! • For n , does x tend to ?! • More generally, does this • tend to the following ? CONJECTURE Scientific computing over the Web

  5. 1.2. 3. Scientific computing: two illustrative problems • Problem 1) Graphically (n = 106), e.g. with a = 4,5: • x0 = 1 • (Very) fast convergence • x0 = 500 • Slowerconvergence • Conjecture: • confirmed ? Scientific computing over the Web

  6. 1.2. 3. Scientific computing: two illustrative problems • Problem 2) What is the distribution of the distance from a given point () to the random points in a circle (R = 1) ? • E.g., for x0 = 0,6: Scientific computing over the Web

  7. 1.2. 3. Scientific computing: two illustrative problems • Problem 2) Is there an analytical expression for these curves ? We used Monte Carlo simulation. • Curves for x0 = 2,2; 0,2; 0. Anyway, for 0: y = 2 x (!) Scientific computing over the Web

  8. Scientific computing: two illustrative problems Solving problems in Fortran, C, and Octave Conclusions Scientific computing over the Webin variousprogramminglanguages Alexandre Rey Colaço (1854-1928) Portuguese composerMadrid Scientific computing over the Web

  9. 1. 2. 3.Solving problems in Fortran, C, and Octave • Problem 1)Problem 2) • Writing the code • Fortran, C: ~3 h; Octave: ~20 min • Executing • Fortran, C: ~5 ms250 ms • Octave: ~70 s115 s Link Scientific computing over the Web

  10. Scientific computing: two illustrative problems Solving problems in Fortran, C, and Octave Conclusions Scientific computing over the Webin variousprogramminglanguages Henrique Medina (1901–1988) Salvador Dalí (1904-1989) Scientific computing over the Web

  11. Scientific computing over the Web has (we think) lagged behind most other aspects in the Web. Making “scientific” (or industrial, etc.) applications accessible over the Web: avoids platform incompatibilities (Windows, Mac, Linux, etc.); and dispenses with any software installation (facilitating work in the classroom and in various enterprise tasks). For many problems such as the ones shown: the “old” (laborious) languages (Fortran, C) work well, indifferently, over the Web or not; and the “new” (productive) languages (Matlab) show various obstacles (licence !, time) --- hence, Octave. 1. 2. 3. Conclusions (1 of 2) Scientific computing over the Web

  12. So, we use and recommend scientific computing over the Web for academic or industrial purposes. For scientificcomputingoverthe Web, onlytheframeworkisdifficult to implement. Furtherapplications can be trivial. So, yourproblems are welcome !  1. 2. 3. Conclusions (2 of 2) Scientific computing over the Web

  13. DEQ, DEI: Department of Chemical Engineering, and Department of Computer Science and Engineering — IST, University of Lisbon CERENA (CPQ): Centre for Natural Resources and the Environment (Centre for Chemical Processes), IST (Ulisboa) CIIST: “Centro de Informática do IST” (Centre for Informatics), IST, ULisboa Milipeia, Lab. de Computação Avançada (Lab. of Advanced Computing), University of Coimbra Prof. Jorge Buescu, Dept. of Mathematics, Faculty of Sciences, ULisboa Keywords Scientific computing, Internet, computer languages Acknowledgements Scientific computing over the Web

  14. Casquilho, M. [2012] “Scientific computing on the Internet, a little-trodden field”, Universidade Aberta, Porto Salvo. Casquilho, M. [2013] “Computação científica, Internet, Indústria” (Scientific computing, Internet, Industry), 1.st Portuguese Meeting on Mathematics for Industry, FCUP, Universidade do Porto, Porto, 06–08 June. Ferreira, Miguel, Miguel Casquilho [2013] "A web application for distributedcomputing — solving a typicalstatisticalproblem in industry", CISTI'2013, 8.ª Conf. Ibérica de Sistemas e Tecnologias de Informação (8.th IberianConf. onInformationSystemsand Technologies), Lisbon (Portugal) Ferreira, M., M. Casquilho [2013] “Scientific computing over the Internet: an example in Geometry”, WorldCIST'13, World Conference on Information Systems and Technologies, Olhão (Portugal) Franco, B., M. Casquilho [2011] “A Web application for scientific computing: combining several tools and languages to solve a statistical problem”, CISTI'2011, 6.ª Conferência Ibérica de Sistemas e Tecnologias de Informação, Chaves (Portugal) Bibliography Scientific computing over the Web

  15. Miguel Casquilho CERENA“Centre for Natural Resources and the Environment” (CPQ) Department of Chemical Engineering Marco Cunha Dept. of Computer Science and Engineering ISTInstituto Superior Técnico UL Universidade de Lisboa(University of Lisbon) http://web.tecnico.ulisboa.pt/mcasquilho/ Scientific computing over the Webin various programming languages Scientific computing over the Web

More Related