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MATHLAB 68
MATHLAB is a computer algebra system created in 1964 by Carl Engelman at MITRE and written in Lisp. "MATHLAB 68" was introduced in 1967 and became rather popular in university environments running on DECs PDP-6 and PDP-10 under TOPS-10 or TENEX. In 1969 this version was included in the DECUS user group's library (as 10-142) as royalty-free software. Carl Engelman left MITRE for Symbolics where he contributed his expert knowledge in the development of Macsyma. Features Abstract from DECUS Library Catalog: MATHLAB is an on-line system providing machine aid for the mechanical symbolic processes encountered in analysis. It is capable of performing, automatically and symbolically, such common procedures as simplification, substitution, differentiation, polynomial factorization, indefinite integration, direct and inverse Laplace transforms, the solution of linear differential equations with constant coefficients, the solution of simultaneous linear equations, and the inversion ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Computer Algebra System
A computer algebra system (CAS) or symbolic algebra system (SAS) is any mathematical software with the ability to manipulate mathematical expressions in a way similar to the traditional manual computations of mathematicians and scientists. The development of the computer algebra systems in the second half of the 20th century is part of the discipline of "computer algebra" or "symbolic computation", which has spurred work in algorithms over mathematical objects such as polynomials. Computer algebra systems may be divided into two classes: specialized and general-purpose. The specialized ones are devoted to a specific part of mathematics, such as number theory, group theory, or teaching of elementary mathematics. General-purpose computer algebra systems aim to be useful to a user working in any scientific field that requires manipulation of mathematical expressions. To be useful, a general-purpose computer algebra system must include various features such as: *a user interface allo ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Symbolics
Symbolics was a computer manufacturer Symbolics, Inc., and a privately held company that acquired the assets of the former company and continues to sell and maintain the Open Genera Lisp system and the Macsyma computer algebra system.Symbolics Sales by David Schmidt The symbolics.com domain was originally registered on March 15, 1985, making it the first -domain in the world. In August 2009, it was sold to napkin.com (formerly XF.com) Investments. History Symbolics, Inc. was a |
Laplace Transform
In mathematics, the Laplace transform, named after its discoverer Pierre-Simon Laplace (), is an integral transform In mathematics, an integral transform maps a function from its original function space into another function space via integration, where some of the properties of the original function might be more easily characterized and manipulated than in ... that converts a Function (mathematics), function of a Real number, real Variable (mathematics), variable (usually t, in the ''time domain'') to a function of a Complex number, complex variable s (in the complex frequency domain, also known as ''s''-domain, or s-plane). The transform has many applications in science and engineering because it is a tool for solving differential equations. In particular, it transforms ordinary differential equations into algebraic equations and convolution into multiplication. For suitable functions ''f'', the Laplace transform is the integral \mathcal\(s) = \int_0^\infty f(t)e^ \, dt. H ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Linear Algebra
Linear algebra is the branch of mathematics concerning linear equations such as: :a_1x_1+\cdots +a_nx_n=b, linear maps such as: :(x_1, \ldots, x_n) \mapsto a_1x_1+\cdots +a_nx_n, and their representations in vector spaces and through matrices. Linear algebra is central to almost all areas of mathematics. For instance, linear algebra is fundamental in modern presentations of geometry, including for defining basic objects such as lines, planes and rotations. Also, functional analysis, a branch of mathematical analysis, may be viewed as the application of linear algebra to spaces of functions. Linear algebra is also used in most sciences and fields of engineering, because it allows modeling many natural phenomena, and computing efficiently with such models. For nonlinear systems, which cannot be modeled with linear algebra, it is often used for dealing with first-order approximations, using the fact that the differential of a multivariate function at a point is the linear ma ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Symbolic Circuit Analysis
Symbolic circuit analysis is a formal technique of circuit analysis to calculate the behaviour or characteristic of an electric/electronic circuit with the independent variables (time or frequency), the dependent variables (voltages and currents), and (some or all of) the circuit elements represented by symbols. When analysing electric/electronic circuits, we may ask two types of questions: What is the value of certain circuit variable (voltage, current, resistance, gain, etc.) or what is the relationship between some circuit variables or between a circuit variable and circuit components and frequency (or time). Such relationship may take the form of a graph, where numerical values of a circuit variable are plotted versus frequency or component value (the most common example would be a plot of the magnitude of a transfer function vs. frequency). Symbolic circuit analysis is concerned with obtaining those relationships in symbolic form, i.e., in the form of analytical expression, wh ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Acausal System
In systems theory, an anticausal system is a hypothetical system with outputs and internal states that depend ''solely'' on future input values. Some textbooks and published research literature might define an anticausal system to be one that does not depend on past input values, allowing also for the dependence on present input values. An acausal system is a system that is not a causal system, that is one that depends on some future input values and possibly on some input values from the past or present. This is in contrast to a causal system which depends only on current and/or past input values.Distinguishing Causal and Acausal Temporal Relations, Kamran Karimi and Howard J. Hamilton, The seventh Pacific-Asia Conference on Knowledge Discovery and Data Mining (PAKDD), 2003. This is often a topic of control theory and digital signal processing (DSP). Anticausal systems are also acausal, but the converse is not always true. An acausal system that has any dependence on pas ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Linear Circuit
A linear circuit is an electronic circuit which obeys the superposition principle. This means that the output of the circuit ''F(x)'' when a linear combination of signals ''ax1(t) + bx2(t)'' is applied to it is equal to the linear combination of the outputs due to the signals ''x1(t)'' and ''x2(t)'' applied separately: :F(ax_1 + bx_2) = aF(x_1) + bF(x_2)\, It is called a linear circuit because the output voltage and current of such a circuit are linear functions of its input voltage and current. This kind of linearity is not the same as that of straight-line graphs. In the common case of a circuit in which the components' values are constant and don't change with time, an alternate definition of linearity is that when a sinusoidal input voltage or current of frequency ''f'' is applied, any steady-state output of the circuit (the current through any component, or the voltage between any two points) is also sinusoidal with frequency ''f''. A linear circuit with constant comp ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Macsyma
Macsyma (; "Project MAC's SYmbolic MAnipulator") is one of the oldest general-purpose computer algebra systems still in wide use. It was originally developed from 1968 to 1982 at MIT's Project MAC. In 1982, Macsyma was licensed to Symbolics and became a commercial product. In 1992, Symbolics Macsyma was spun off to Macsyma, Inc., which continued to develop Macsyma until 1999. That version is still available for Microsoft's Windows XP operating system. The 1982 version of MIT Macsyma remained available to academics and US government agencies, and it is distributed by the US Department of Energy (DOE). That version, DOE Macsyma, was maintained by Bill Schelter. Under the name of Maxima, it was released under the GPL in 1999, and remains under active maintenance. Development The project was initiated in July, 1968 by Carl Engelman, William A. Martin (front end, expression display, polynomial arithmetic) and Joel Moses (simplifier, indefinite integration: heuristic/Risch). Martin ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
DECUS
The Digital Equipment Computer Users' Society (DECUS) was an independent computer user group related to Digital Equipment Corporation (DEC). The Connect User Group Community, formed from the consolidation in May, 2008 of DECUS, Encompass, HP-Interex, and ITUG is the Hewlett-Packard’s largest user community, representing more than 50,000 participants. History DECUS was the Digital Equipment Computer Users' Society, a users' group for Digital Equipment Corporation (DEC) computers. Members included companies and organizations who purchased DEC equipment; many members were application programmers who wrote code for DEC machines or system programmers who managed DEC systems. DECUS was founded in March 1961 by Edward Fredkin. DECUS was legally a part of Digital Equipment Corporation and subsidized by the company; however, it was run by unpaid volunteers. Digital staff members were not eligible to join DECUS, yet were allowed and encouraged to participate in DECUS activities. D ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Carl Engelman
Carl Engelman (October 21, 1929 – November 26, 1983) was an American computer scientist. Carl is best known as the creator of MATHLAB. He was employed by Mitre Corporation and Symbolics. He was a visiting professor at the University of Turin through a grant provided by National Research Council (Italy) The National Research Council (Italian: ''Consiglio Nazionale delle Ricerche, CNR'') is the largest research council in Italy. As a public organisation, its remit is to support scientific and technological research. Its headquarters are in Rome. .... References {{DEFAULTSORT:Engelman, Carl 1929 births 1983 deaths 20th-century American mathematicians American computer scientists Burials at Mount Auburn Cemetery ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
TENEX (operating System)
TENEX is an operating system developed in 1969 by BBN for the PDP-10, which later formed the basis for Digital Equipment Corporation's TOPS-20 operating system. Background In the 1960s, BBN was involved in a number of LISP-based artificial intelligence projects for DARPA, many of which had very large (for the era) memory requirements. One solution to this problem was to add ''paging'' software to the LISP language, allowing it to write out unused portions of memory to disk for later recall if needed. One such system had been developed for the PDP-1 at MIT by Daniel Murphy before he joined BBN. Early DEC machines were based on an 18-bit word, allowing addresses to encode for a 256 kiloword memory. The machines were based on expensive core memory and included nowhere near the required amount. The pager used the most significant bits of the address to index a table of blocks on a magnetic drum that acted as the pager's ''backing store''. The software would fetch the pages if nee ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
TOPS-10
TOPS-10 System (''Timesharing / Total Operating System-10'') is a discontinued operating system from Digital Equipment Corporation (DEC) for the PDP-10 (or DECsystem-10) mainframe computer family. Launched in 1967, TOPS-10 evolved from the earlier "Monitor" software for the PDP-6 and PDP-10 computers; this was renamed to TOPS-10 in 1970. Overview TOPS-10 supported shared memory and allowed the development of one of the first true multiplayer computer games. The game, called DECWAR, was a text-oriented ''Star Trek'' type game. Users at terminals typed in commands and fought each other in real time. TOPS-10 was also the home of the original Multi User Dungeon, MUD, the fore runner to today's MMORPGs. Another groundbreaking application was called ''FORUM''. This application was perhaps the first so-called ''CB Simulator'' that allowed users to converse with one another in what is now known as a chat room. This application showed the potential of multi-user communication and led ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
