Porovnanie Súčasných Systémov Počítačovej Algebry

Total Page:16

File Type:pdf, Size:1020Kb

Porovnanie Súčasných Systémov Počítačovej Algebry Masarykova univerzita Fakulta informatiky Porovnanie súčasných systémov počítačovej algebry Bakalárska práca Peter Gábor Brno, jar 2018 Masarykova univerzita Fakulta informatiky Porovnanie súčasných systémov počítačovej algebry Bakalárska práca Peter Gábor Brno, jar 2018 Na tomto mieste sa v tlačenej práci nachádza oficiálne podpísané zadanie práce a vyhlásenie autora školského diela. Vyhlásenie Vyhlasujem, že táto bakalárska práca je mojím pôvodným autorským dielom, ktoré som vypracoval samostatne. Všetky zdroje, pramene a literatúru, ktoré som pri vypracovaní používal alebo z nich čerpal, v práci riadne citujem s uvedením úplného odkazu na príslušný zdroj. Peter Gábor Vedúci práce: RNDr. Jaroslav Ráček Ph.D. i Poďakovanie Na tomto mieste by som sa chcel poďakovať vedúcemu bakalárskej práce RNDr. Jaroslavovi Ráčkovi Ph.D. za cenné rady, trpezlivosť a odborné vedenie pri vytváraní tejto práce. iii Zhrnutie Cieľom práce je vytvoriť komplexné zhodnotenie kvalít a vzájomné porovnanie systémov počítačovej algebry. V práci sa zmeriavam na piatich zástupcov spomedzi univerzálnych systémov počítačovej al- gebry. Konkrétne sa jedná o systémy Maple, Mathematica, MATLAB, Maxima a SageMath. Tieto systémy hodnotím z pohľadu užívateľskej a programátorskej prívetivosti, licenčnej a cenovej politiky a poskyto- vanej funkcionality. Súčasťou práce je vypracovanie (implementácia) spoločných vzorových úloh v prostrediach jednotlivých systémov, na ktorých demonštrujem charakter programovacieho jazyka, ako aj výpočtovú silu daného systému. iv Kľúčové slová počítačová algebra, systém počítačovej algebry, computer algebra sys- tem, CAS, Maple, Mathematica, SageMath, Maxima, MATLAB, po- rovnanie, hodnotenie, funkcionalita, kritéria, ... v Obsah Úvod 1 1 Prehľad systémov počítačovej algebry 3 1.1 Upresnenie pojmov ......................3 1.2 Historický vývoj ........................3 1.3 Princípy súčasných systémov .................4 2 Zameranie práce 7 2.1 Účel porovnávania ......................7 2.2 Výber systémov ........................8 2.3 Kritéria hodnotenia ......................9 2.3.1 Navrhnuté kritériá . 10 2.3.2 Ďalšie kritériá . 13 2.4 Vzorové úlohy ......................... 13 2.4.1 Úloha č. 1: Riešenie diferenciálnych rovníc . 14 2.4.2 Úloha č.2: Geometria v rovine a priestore . 16 2.5 Použitý hardvér a softvér ................... 17 3 Porovnávanie vybraných systémov 19 3.1 Maple ............................. 19 3.2 Mathematica ......................... 25 3.3 MATLAB ........................... 31 3.4 Maxima ............................ 37 3.5 SageMath ........................... 42 4 Vyhodnotenie 49 4.1 Hodnotenie z vlastných skúseností .............. 50 5 Záver 53 Bibliografia 55 A Prílohy 59 vii Úvod Systémy počítačovej algebry (známe tiež ako CAS, z anglického: Com- puter algebra systems) v dnešnej dobe predstavujú revolúciu v ob- lasti výučby matematiky, vedeckých štúdií a inžinierstva. Užívate- ľom poskytujú nástroje pre úpravu matematických výrazov, nájdenie presných alebo aspoň približných výsledkov z matematickej analýze, numerické výpočty a grafické ilustrácie. Prvé matematické balíky sa začínajú objavovať v šesťdesiatych ro- kov 20. storočia [1]. Spočiatku sa jednalo o špecializované systémy, ktoré boli určené len pre konkrétne oblasti, resp. problémy v mate- matike alebo fyzike. Snaha o rozšírenie škály použitia jednotlivých systémov viedla k myšlienke vytvoriť moderný univerzálny systém počítačovej algebry. Prvé univerzálne CAS sa objavujú začiatkom se- demdesiatych rokov, ktoré odštartovali rozsiahly výskum v oblasti počítačovej algebry, ako aj dynamický vývoj CAS. Dodnes bolo vyvi- nutých viac ako sto rôznych CAS [2]. V dôsledku dynamiky tohto vývoja a širokej ponuky CAS na trhu si zákazník často nedokáže vybrať systém, ktorý by najviac vyhovoval jeho potrebám. Cieľom mojej bakalárskej práce je poskytnúť potenciál- nym zákazníkom nástroj pre porovnanie a zhodnotenie kvalít CAS v jednotlivých aspektoch. V práci sa zameriavam na vybraných zástupcov spomedzi uni- verzálnych CAS. Konkrétne sa jedná o systémy Maple, Mathematica, MATLAB, Maxima a SageMath. Tieto systémy posudzujem a testujem z hľadiska mnou zvolených spoločných kritérií a na základe skúseností, ktoré som nadobudol pri vypracovávaní vzorových úloh. V prvej kapitole upresňujem definície základných pojmov, uvá- dzam stručný historický vývoj a popisujem základné princípy súčas- ných CAS. Obsahom druhej kapitoly je výber CAS, ako aj špecifiká- cia spoločných kritérií a vzorových úloh, na základe ktorých budem vybrané systémy hodnotiť. Tretia kapitola obsahuje predstavenie, re- alizáciu vzorových úloh a následné hodnotenie v optike spoločných kritérií pre jednotlivé systémy. V štvrtej kapitola uvádzam sumárne vyhodnotenie doplnené hodnotením systémov na základe vlastných skúseností. 1 1 Prehľad systémov počítačovej algebry 1.1 Upresnenie pojmov Počítačová algebra (Computer algebra) je odvetvie vedy o počítačoch (Computer science), ktorá sa zaoberá návrhom, analýzou, implemen- táciou a aplikáciou algebrických algoritmov [2]. Systém počítačovej algebry (computer algebra system, CAS) je matema- tický balík obsahujúci algoritmy pre spracovanie symbolických mate- matických výrazov, jazyk pre implementáciu a prostredie pre použitie jazyka (interpreter) [3, str. 123]. Paralelné výpočty (parallel computing) je pojem, ktorým sa označuje súčasné (simultánne) použitie viacerých výpočtových zdrojov na rie- šenie jedného výpočtového problému. Problém je zvyčajne rozdelený na viacero menších častí, ktoré môžu byť riešené súbežne. Každá časť je ďalej rozdelená na sériu inštrukcií. Inštrukcie z každej časti sú vy- konané súčasne na rôznych procesoroch, resp. jadrách procesoru [4, kap. 2]. Výpočtový klaster (computer cluster) je zoskupenie viacerých úzko spolupracujúcich počítačov (zväčša prepojených počítačovou sieťou), určených pre výpočet náročných úloh [5, kap. 1]. HPC centrum (High Performance Computing Center, HPC center) je názov pre stredisko viacerých výpočtových klastrov (superpočítačov) [6]. Grafický procesor (graphics processing unit, GPU) je procesor slúžiaci na výpočet grafických operácií ako vektorové výpočty, spracovanie ob- razu a mapovanie grafických informácií na informácie pre zobrazenie [6]. 1.2 Historický vývoj V šesťdesiatych rokoch 20. storočia sa začínajú objavovať prvé matema- tické balíky určené na riešenie špecifických numerických, analytických, grafických a iných problémov [1]. V roku 1961, fyzik Martinus J.G. Veltman navrhol program nazvaný Schoonschip (Dutch for "clean ship") určený pre výpočty v časticovej fyzike (high energy physics) [7, 8]. Ďalším príkladom je systém FORMAC; vyvíjaný firmou IBM 3 1. Prehľad systémov počítačovej algebry v rokoch 1962 – 1964 [9]. Implementovaný bol v jazyku FORTRAN a umožňoval jednoduché spracovanie funkcií a polynómov. V roku 1964, Carl Engelman vytvoril, v centre pre výskum umelej inteligencie, systém MATHLAB (mathematical laboratory) [9, 7]. Nejedná sa však o systém počítačovej algebry MATLAB, ktorý vznikol asi až o 15 rokov neskôr. Sedemdesiate roky odštartovali rozsiahly výskum v oblasti počíta- čovej algebry, ako aj dynamický vývoj CAS. Do dnes bolo vyvinutých viac ako sto rôznych CAS [2]. 1.3 Princípy súčasných systémov Systémy počítačovej algebry môžeme rozdeliť do dvoch kategórií: špe- cializované (specialized alebo special-purpose CAS) a univerzálne (general-purpose CAS). Špecializované systémy sú navrhnuté pre kon- krétny problém alebo odvetvie vo fyzike alebo matematike. Medzi známe špecializované systémy vo fyzike patria Schoonship (high- energy physics), CAMAL (celestial mechanics), SHEEP a STENSOR (general relativity) [7, 8, 10]. V oblasti matematiky poznáme Cayley a GAP (teória grúp), PARI, SIMATH a KANT (teória čísel), CoCoA (commutative algebra), Macaulay a SINGULAR (algebraic geometry a commutative algebra) [11]. Špecializované systémy zohrali dôležitú úlohy pri viacerých vedeckých výskumoch a projektoch. Veľakrát sú elegantnejšie a efektívnejšie ako univerzálne systémy vďaka špecific- kým dátovým štruktúram a implementácii v nižších programovacích jazykoch. Avšak v mojej práci sa zameriavam na univerzálne systémy počí- tačovej algebry. Univerzálne CAS sa snažia pokryť čo najviac oblastí možnej aplikácie. Funkcionalitu súčasných univerzálnych CAS tvorí: úprava symbolických matematických výrazov, diferenciálne počty, rovnice (vrátane diferenciálnych, diofantických alebo rekurentných), nerovnice, teória grafov, teória čísel, úprava a valuácia logických for- múl, kryptografia, teória pravdepodobnosti, grúp a ďalšie funkcie. Na základe cenovej a licenčnej politiky rozlišujeme platené a voľne dostupné (free, open-source) systémy. Medzi platené systémy patria Mathematica, Maple, MATLAB, Magma a iné. K voľne dostupným sa 4 1. Prehľad systémov počítačovej algebry zaradzujú SageMath, FriCas, Axiom, Xcas/Giac, OpenAxiom, Maxima a mnoho ďalších. Systémy počítačovej algebry typicky pozostávajú z troch častí: roz- siahlej knižnice vstavaných funkcií a algoritmov, výpočtovej jednotky, jadra (kernel) a grafického užívateľského rozhrania. 5 2 Zameranie práce 2.1 Účel porovnávania Účelom môjho porovnávania v rámci tejto práce je pomôcť ľuďom, ktorý sa zaujímajú o systémy počítačovej algebry s výberom systému, ktorý bude čo najlepšie vyhovovať ich požiadavkám. Výber vhodného systému počítačovej algebry nie je pre zákazníka jednoduchý a to hneď z niekoľkých dôvodov. V porovnaní so špecializovanými systémami počítačovej algebry sú si univerzálne CAS v mnohých aspektoch podobné. Spoločnou stránkou viacerých systémov
Recommended publications
  • CAS (Computer Algebra System) Mathematica
    CAS (Computer Algebra System) Mathematica- UML students can download a copy for free as part of the UML site license; see the course website for details From: Wikipedia 2/9/2014 A computer algebra system (CAS) is a software program that allows [one] to compute with mathematical expressions in a way which is similar to the traditional handwritten computations of the mathematicians and other scientists. The main ones are Axiom, Magma, Maple, Mathematica and Sage (the latter includes several computer algebras systems, such as Macsyma and SymPy). Computer algebra systems began to appear in the 1960s, and evolved out of two quite different sources—the requirements of theoretical physicists and research into artificial intelligence. A prime example for the first development was the pioneering work conducted by the later Nobel Prize laureate in physics Martin Veltman, who designed a program for symbolic mathematics, especially High Energy Physics, called Schoonschip (Dutch for "clean ship") in 1963. Using LISP as the programming basis, Carl Engelman created MATHLAB in 1964 at MITRE within an artificial intelligence research environment. Later MATHLAB was made available to users on PDP-6 and PDP-10 Systems running TOPS-10 or TENEX in universities. Today it can still be used on SIMH-Emulations of the PDP-10. MATHLAB ("mathematical laboratory") should not be confused with MATLAB ("matrix laboratory") which is a system for numerical computation built 15 years later at the University of New Mexico, accidentally named rather similarly. The first popular computer algebra systems were muMATH, Reduce, Derive (based on muMATH), and Macsyma; a popular copyleft version of Macsyma called Maxima is actively being maintained.
    [Show full text]
  • Nonlinear Evolution Equations and Solving Algebraic Systems: the Importance of Computer Algebra
    - Y'M?S </#i/ ИНСТИТУТ ядерных исследований дубна Е5-89-62Ц V.P.Gerdt, N.A.Kostov, A.Yu.Zharkov* NONLINEAR EVOLUTION EQUATIONS AND SOLVING ALGEBRAIC SYSTEMS: THE IMPORTANCE OF COMPUTER ALGEBRA Submitted to International Conference "Solitons and its Applications", Dubna, August 25-27, 1989 * Saratov State University, USSR 1989 1.INTRODUCTION A wide-spread problem in the theory of nonlinear evolution equations (NEE) is to find the exact solutions of complicated algebraic systems. For example, let us consider the following evolution systems U - AU + F(U,U , ..U ), U=U(x,t)-(U1, . ,UH) , U=D1(U), D=d/dx IN 1 N-1 I /ii F«(F\ . -FH) , A==diag(A , . .A) , A *0, A *A , (i*j). The general symmetry approach to checking up the integrability and classification of integrable NEE (see the reviews [1,2] and references therein) allows to obtain the integrability conditions which are related to existence of higher order symmetries and conservation laws in a fully algorithmic way. The implementation of these algorithms in a form of FORMAC program FORMINT have been given for scalar equations (M=l in (1)) in [3 j and for the general case (M>1) in [4]. Using this program one can automatically obtain the equations in right hand side of (l) which follow from the necessary integrability conditions. The integrabiiity conditions for the right hand side with arbitrary functions have the form of systems of differential equations, the procedure of solving these equations is not generally algorithmic. But in the important particular cases when the right hand side F are polynomials and the integrability conditions are reduced to a system of nonlinear algebraic equations in coefficients of the polynomials.
    [Show full text]
  • WORKSHOP on COMPUTATIONAL ASPECTS in the CONTROL of FLEXIBLE SYSTEMS
    NASA Technical Memorandum 10 1578, Part One WORKSHOP on COMPUTATIONAL ASPECTS in the CONTROL of FLEXIBLE SYSTEMS Held at the Royce Hotel in WiIIiamsburg, Virginia (\!~?~-~*-lolj?d-pt-l) P&~C~L~IN~Y-F THE <UL (; 8.; t\jo~-l?~Su ~~KY,~+~JDfl~CnHPUTATIONAL ASPFCTI IY TcF --T )~uI)-- ~f'4T1.1L dC Ei'XfrLt. >Y>TtU,, f'AQT i (.\A>A- r\eu-lP>CL L an-1-y Rps~arihCentnr) 492 p C5CL 2LR UnLl ~s 55 3 G;/i3 J,'i74qA Sponsored by the NASA Langley Research Center Proceedings Compiled by Larry Taylor Table of Contents Page Introduction Computational Aspects Workshop Call for Papers 1 Workshop Organizing Committee 5 Attendance List 7 --------___-----__-------------------------------------- Needs for Advanced CSI Software NASA's Control/Structures Interaction (CSI) Program Brantley R. Hanks, NASA Langley Research Center 21-, Computational Controls for Aerospace Systems Guy Man, Robert A. Laskin and A. Fernando Tolivar Jet Propulsion Laboratory 33. Additional Software Developments Wanted for Modeling and Control of Flexible Systems Jiguan G. Lin, Control Research Corporation 4 9 Survey of Available Software Flexible Structure Control Experiments Using a Real-Time Workstation for Computer-Aided Control Engineering Michael E. Steiber, Communications Research Centre 6 7 CONSOLE: A CAD Tandem for Optimizationl-Based Design Interacting with User-Supplied Simulators Michael K.H. Fan, Li-Shen Wang, Jan Koninckx and Andre L. Tits,University of Maryland, College Park 8 9 mLPAGE IS QUALfTY ORIGINAL PAGE IS OF POOR QUALITY The Application of TSIM Software to ACT Design and Analysis of Flexible Aircraft Ian W. Kaynes, Royal Aerospace Establishment, Farnborouth 109 - Control/Structure Interaction Methods for Space Statian Power Systems Paul Blelloch, Structural Dynamics Research Corporation 121L, Flexible Missile Autopilot Design Studies with PC-MATLAB386 Michael J.
    [Show full text]
  • (12) United States Patent (10) Patent No.: US 6,203,987 B1 Friend Et Al
    USOO6203987B1 (12) United States Patent (10) Patent No.: US 6,203,987 B1 Friend et al. (45) Date of Patent: Mar. 20, 2001 (54) METHODS FOR USING CO-REGULATED Garrels, JI et al “Quant exploration of the REF52 protein GENESETS TO ENHANCE DETECTION AND database: cluster analysis reveals major protein expression CLASSIFICATION OF GENE EXPRESSION profiles in resonses to growth regulation, Serum Stimulation, PATTERNS and viral transformation’, Electrophoresis, 12/90, 11(12): 1114–30.* (75) Inventors: Stephen H. Friend, Seattle, WA (US); Anderson et al., 1994, “Involvement of the protein tyrosine Roland Stoughton, San Diego, CA kinase p56' in T cell signaling and thymocyte develop (US) ment.” Adv. Immunol. 56:151-178. (73) Assignee: Rosetta Inpharmatics, Inc., Kirkland, Anderson, 1995, “Mutagenesis", Methods Cell. Biol. 48:31. WA (US) Baudin et al., 1993, “A simple and efficient method for direct gene deletion in Saccharomyces cerevisiae, ' Nucl. Acids (*) Notice: Subject to any disclaimer, the term of this ReS. 21:3329-3330. patent is extended or adjusted under 35 Belshaw et al., 1996, “Controlling protein association and U.S.C. 154(b) by 0 days. Subcellular localization with a Synthetic ligand that induces heterodimerization of proteins,” Proc. Natl. Acad. Sci. USA (21) Appl. No.: 09/179,569 93:46O4-46O7. (22) Filed: Oct. 27, 1998 Bernoist and Chambon, 1981, “In vivo sequence require ments of the SV40 early promoter region”, Nature 290: (51) Int. Cl. ............................ C12O 1/68; C12P 21/04; 304-310. GO1N 33/543 Biocca, 1995, “Intracellular immunization: antibody target ing to subcellular compartments,” Trends in Cell Biology (52) U.S.
    [Show full text]
  • A Review of Mathematica
    A Review of Mathematica RICHARD J. FATEMAN ∗ [email protected] Computer Science Division, University of California, Berkeley, CA 94720, USA 16 September 1991 Abstract The Mathematica computer system is reviewed from the perspective of its contributions to symbolic and algebraic computation, as well as its stated goals. Design and implementation issues are discussed. 1 Introduction The Mathematica1 computer program is a general system for doing mathematical computation [51][52]. It includes a command language, a programming language, and a calculation environment that is oriented toward symbolic as well as numeric mathematics. The back cover of the manual [52] provides excerpts from rave notices like “The importance of [Mathematica] cannot be overlooked. it so fundamentally alters the mechanics of mathematics.” —The New York Times. Fortune [47] says “. it will do, instantaneously, virtually all of applied mathematics. .” Hype aside, the program is without question interesting to mathematicians, computer scientists, and engineers because of its combination of a number of ∗This work has been supported in part by the following: the National Science Foundation under grant numbers CCR-8812843 and CDS-8922788, through the Center for Pure and Applied Mathe- matics and the Electronics Research Laboratory (ERL) at the University of California at Berkeley; the Defense Advanced Research Projects Agency (DoD) ARPA order #4871, monitored by Space & Naval Warfare Systems Command under contract N00039-84-C-0089, through ERL; and grants from the IBM Corporation, the State of California MICRO program, and Sun Microsystems. 1 Mathematica is a trademark of Wolfram Research Inc. (WRI). 1 technologies that have arisen in initially separate contexts—numerical and sym- bolic mathematics, graphics, and modern user interfaces.
    [Show full text]
  • SMT Solving in a Nutshell
    SAT and SMT Solving in a Nutshell Erika Abrah´ am´ RWTH Aachen University, Germany LuFG Theory of Hybrid Systems February 27, 2020 Erika Abrah´ am´ - SAT and SMT solving 1 / 16 What is this talk about? Satisfiability problem The satisfiability problem is the problem of deciding whether a logical formula is satisfiable. We focus on the automated solution of the satisfiability problem for first-order logic over arithmetic theories, especially using SAT and SMT solving. Erika Abrah´ am´ - SAT and SMT solving 2 / 16 CAS SAT SMT (propositional logic) (SAT modulo theories) Enumeration Computer algebra DP (resolution) systems [Davis, Putnam’60] DPLL (propagation) [Davis,Putnam,Logemann,Loveland’62] Decision procedures NP-completeness [Cook’71] for combined theories CAD Conflict-directed [Shostak’79] [Nelson, Oppen’79] backjumping Partial CAD Virtual CDCL [GRASP’97] [zChaff’04] DPLL(T) substitution Watched literals Equalities and uninterpreted Clause learning/forgetting functions Variable ordering heuristics Bit-vectors Restarts Array theory Arithmetic Decision procedures for first-order logic over arithmetic theories in mathematical logic 1940 Computer architecture development 1960 1970 1980 2000 2010 Erika Abrah´ am´ - SAT and SMT solving 3 / 16 SAT SMT (propositional logic) (SAT modulo theories) Enumeration DP (resolution) [Davis, Putnam’60] DPLL (propagation) [Davis,Putnam,Logemann,Loveland’62] Decision procedures NP-completeness [Cook’71] for combined theories Conflict-directed [Shostak’79] [Nelson, Oppen’79] backjumping CDCL [GRASP’97] [zChaff’04]
    [Show full text]
  • Another Formulation of the Wick's Theorem. Farewell, Pairing?
    Spec. Matrices 2015; 3:169–174 Communication Open Access Igor V. Beloussov Another formulation of the Wick’s theorem. Farewell, pairing? DOI 10.1515/spma-2015-0015 Received February 19, 2015; accepted July 2, 2015 Abstract: The algebraic formulation of Wick’s theorem that allows one to present the vacuum or thermal averages of the chronological product of an arbitrary number of field operators as a determinant (permanent) of the matrix is proposed. Each element of the matrix is the average of the chronological product of only two operators. This formulation is extremely convenient for practical calculations in quantum field theory, statistical physics, and quantum chemistry by the standard packages of the well known computer algebra systems. Keywords: vacuum expectation value; chronological product; contractions AMS: 15-04, 15A15, 65Z05, 81U20 1 Introduction Wick’s theorems are used extensively in quantum field theory [1–4], statistical physics [5–7], and quantum chemistry [8]. They allow one to use the Green’s functions method, and consequently to apply the Feynman’s diagrams for investigations [1–3]. The first of these, which can be called Wick’s Theorem for Ordinary Products, gives us the opportunity to reduce in almost automatic mode the usual product of operators into a unique sum of normal products multiplied by c–numbers. It can be formulated as follows [4]. Let Ai (xi) (i = 1, 2, ... , n ) are “linear operators”, i.e., some linear combinations of creation and annihilation operators. Then the ordi- nary product of linear operators is equal to the sum of all the corresponding normal products with all possible contractions, including the normal product without contractions, i.e., A1 ...An = : A1 ...An : +: A1A2 ...An : + ..
    [Show full text]
  • Insight MFR By
    Manufacturers, Publishers and Suppliers by Product Category 11/6/2017 10/100 Hubs & Switches ASCEND COMMUNICATIONS CIS SECURE COMPUTING INC DIGIUM GEAR HEAD 1 TRIPPLITE ASUS Cisco Press D‐LINK SYSTEMS GEFEN 1VISION SOFTWARE ATEN TECHNOLOGY CISCO SYSTEMS DUALCOMM TECHNOLOGY, INC. GEIST 3COM ATLAS SOUND CLEAR CUBE DYCONN GEOVISION INC. 4XEM CORP. ATLONA CLEARSOUNDS DYNEX PRODUCTS GIGAFAST 8E6 TECHNOLOGIES ATTO TECHNOLOGY CNET TECHNOLOGY EATON GIGAMON SYSTEMS LLC AAXEON TECHNOLOGIES LLC. AUDIOCODES, INC. CODE GREEN NETWORKS E‐CORPORATEGIFTS.COM, INC. GLOBAL MARKETING ACCELL AUDIOVOX CODI INC EDGECORE GOLDENRAM ACCELLION AVAYA COMMAND COMMUNICATIONS EDITSHARE LLC GREAT BAY SOFTWARE INC. ACER AMERICA AVENVIEW CORP COMMUNICATION DEVICES INC. EMC GRIFFIN TECHNOLOGY ACTI CORPORATION AVOCENT COMNET ENDACE USA H3C Technology ADAPTEC AVOCENT‐EMERSON COMPELLENT ENGENIUS HALL RESEARCH ADC KENTROX AVTECH CORPORATION COMPREHENSIVE CABLE ENTERASYS NETWORKS HAVIS SHIELD ADC TELECOMMUNICATIONS AXIOM MEMORY COMPU‐CALL, INC EPIPHAN SYSTEMS HAWKING TECHNOLOGY ADDERTECHNOLOGY AXIS COMMUNICATIONS COMPUTER LAB EQUINOX SYSTEMS HERITAGE TRAVELWARE ADD‐ON COMPUTER PERIPHERALS AZIO CORPORATION COMPUTERLINKS ETHERNET DIRECT HEWLETT PACKARD ENTERPRISE ADDON STORE B & B ELECTRONICS COMTROL ETHERWAN HIKVISION DIGITAL TECHNOLOGY CO. LT ADESSO BELDEN CONNECTGEAR EVANS CONSOLES HITACHI ADTRAN BELKIN COMPONENTS CONNECTPRO EVGA.COM HITACHI DATA SYSTEMS ADVANTECH AUTOMATION CORP. BIDUL & CO CONSTANT TECHNOLOGIES INC Exablaze HOO TOO INC AEROHIVE NETWORKS BLACK BOX COOL GEAR EXACQ TECHNOLOGIES INC HP AJA VIDEO SYSTEMS BLACKMAGIC DESIGN USA CP TECHNOLOGIES EXFO INC HP INC ALCATEL BLADE NETWORK TECHNOLOGIES CPS EXTREME NETWORKS HUAWEI ALCATEL LUCENT BLONDER TONGUE LABORATORIES CREATIVE LABS EXTRON HUAWEI SYMANTEC TECHNOLOGIES ALLIED TELESIS BLUE COAT SYSTEMS CRESTRON ELECTRONICS F5 NETWORKS IBM ALLOY COMPUTER PRODUCTS LLC BOSCH SECURITY CTC UNION TECHNOLOGIES CO FELLOWES ICOMTECH INC ALTINEX, INC.
    [Show full text]
  • Using a Small Algebraic Manipulation System to Solve Differential and Integral Equations by Variational and Approximation Techniques
    J. Symbolic Computation (1987) 3, 291-301 Using a Small Algebraic Manipulation System to Solve Differential and Integral Equations by Variational and Approximation Techniques R. D. MILLS Computing Science Department. University of Glasgow, Glasgow, UK (Received 2 December 1985) The microcomputer algebraic manipulation system MUMATH is used to implement the classical variational, Galerkin and least-squares techniques for solving boundary-value problems in differential equations and also for solving Fredhohn integral equations. Examples are given which extend the precision of known results. The technique is presented as a general algorithm which can readily be implemented on other algebraic manipulation systems. 1. Introduction Computer programs have been in existence since the fifties to manipulate polynomials, differentiate functions and solve equations. By the late sixties and early seventies programs were written which could integrate functions analytically. The late seventies saw the development of programs for the symbolic solution of differential and integral equations (see Golden, 1977; Stoutemyer, 1977; Bogen, 1979). Large and complex algebraic manipulation systems were devised to implement the algorithms which effect these processes, the best known being FORMAC, REDUCE2, MACSYMA and SCRATCHPAD. There then opened up the exciting possibility of tackling many problems in applied mathematics and engineering which could be solved approximately by analytical methods but which require very large amounts of algebraic manipulation. The Rayleigh-Ritz, Galerkin and least-squares methods for solving boundary-value problems in differential equations are typical examples. For early work using computer algebra in these methods, see Miola (1974) and Andersen & Noor (1977). This application area involves the interaction of numerical and algebraic computation (see Ng, 1979).
    [Show full text]
  • Symbolic Software for Lie Symmetry Computations
    Invited Lecture 1 Symbolic Software for Lie Symmetry Computations Willy Hereman Dept. Mathematical and Computer Sciences Colorado School of Mines Golden, CO 80401-1887 U.S.A. ISLC Workshop Nordfjordeid, Norway Tuesday, June 18, 1996 16:00 I. INTRODUCTION Symbolic Software • Solitons via Hirota’s method (Macsyma & Mathematica) • Painlev´etest for ODEs or PDEs (Macsyma & Mathematica) • Conservation laws of PDEs (Mathematica) • Lie symmetries for ODEs and PDEs (Macsyma) Purpose of the programs • Study of integrability of nonlinear PDEs • Exact solutions as bench mark for numerical algorithms • Classification of nonlinear PDEs • Lie symmetries −→ solutions via reductions • Work in collaboration with Unal¨ G¨okta¸s Chris Elmer Wuning Zhuang Ameina Nuseir Mark Coffey Erik van den Bulck Tony Miller Tracy Otto Symbolic Software by Willy Hereman and Collaborators Software is freely available from anonymous FTP site: mines.edu Change to subdirectory: pub/papers/math cs dept/software Subdirectory Structure: – symmetry (Macsyma) systems of ODEs and PDEs systems of difference-differential equations – hirota (Macsyma) – painleve (Macsyma) single system – condens (Mathematica) – painmath (Mathematica) single system – hiromath (Mathematica) Computation of Lie-point Symmetries – System of m differential equations of order k ∆i(x, u(k)) = 0, i = 1, 2, ..., m with p independent and q dependent variables p x = (x1, x2, ..., xp) ∈ IR u = (u1, u2, ..., uq) ∈ IRq – The group transformations have the form x˜ = Λgroup(x, u), u˜ = Ωgroup(x, u) where the functions Λgroup
    [Show full text]
  • SCHOONSCHIP, the Largest Time Equationand the Continuous
    Vol. 52 (2021) Acta Physica Polonica B No 6–7 SCHOONSCHIP, THE LARGEST TIME EQUATION AND THE CONTINUOUS DIMENSIONAL REGULARISATION Ettore Remiddi Dipartimento di Fisica e Astronomia, University of Bologna, Italy [email protected] (Received May 11, 2021; accepted May 21, 2021) I will recall three results of Martinus J.G. Veltman, which had a sub- stantial importance in my scientific activity and which gave me the occasion of meeting him and of appreciating the great human and scientific gifts of his unforgettable personality. DOI:10.5506/APhysPolB.52.513 1. Introduction Tini Veltman had a highly positive, strong influence on my whole pro- fessional activity, although I was not a student of his and I never coauthored a paper with him or under his supervision. He was ten years older than me, taller — and with an imposing beard. The first time we exchanged letters I addressed him as “Dear Tiny, . ”, as I had never heard anyone calling him Martinus; in his answer, he replied: “Do I look tiny to you?” (but I think that happened also to other people). I got acquainted with him in 1968 at CERN. In those years, he was still young, but already rather authoritative, at the first sight I felt somewhat intimidated, but soon he became for me a kind of “senior friend”, ready to help and always to be listened to with attention. In this paper, I will recall in the three sections which follow, three of his many scientific results, for the importance that they had on my whole pro- fessional life, and for the occasion which they gave me of knowing him and of entering in contact with his unforgettable personality.
    [Show full text]
  • Modeling and Analysis of Hybrid Systems
    Building Bridges between Symbolic Computation and Satisfiability Checking Erika Abrah´ am´ RWTH Aachen University, Germany in cooperation with Florian Corzilius, Gereon Kremer, Stefan Schupp and others ISSAC’15, 7 July 2015 Photo: Prior Park, Bath / flickr Liam Gladdy What is this talk about? Satisfiability problem The satisfiability problem is the problem of deciding whether a logical formula is satisfiable. We focus on the automated solution of the satisfiability problem for first-order logic over arithmetic theories, especially on similarities and differences in symbolic computation and SAT and SMT solving. Erika Abrah´ am´ - SMT solving and Symbolic Computation 2 / 39 CAS SAT SMT (propositional logic) (SAT modulo theories) Enumeration Computer algebra DP (resolution) systems [Davis, Putnam’60] DPLL (propagation) [Davis,Putnam,Logemann,Loveland’62] Decision procedures NP-completeness [Cook’71] for combined theories CAD Conflict-directed [Shostak’79] [Nelson, Oppen’79] backjumping Partial CAD Virtual CDCL [GRASP’97] [zChaff’04] DPLL(T) substitution Watched literals Equalities and uninterpreted Clause learning/forgetting functions Variable ordering heuristics Bit-vectors Restarts Array theory Arithmetic Decision procedures for first-order logic over arithmetic theories in mathematical logic 1940 Computer architecture development 1960 1970 1980 2000 2010 Erika Abrah´ am´ - SMT solving and Symbolic Computation 3 / 39 SAT SMT (propositional logic) (SAT modulo theories) Enumeration DP (resolution) [Davis, Putnam’60] DPLL (propagation) [Davis,Putnam,Logemann,Loveland’62]
    [Show full text]