Computers instruction code

BASIC. It means Beginner s All-purpose Symbolic Instruction Code and was developed by John Kemeny and Thomas Kurtz (1963). Basic is easy to learn and use. It was mainly designed to be used as an interactive language. Almost every computer manufacturer provides, BASIC on its machines. BASIC is probably the most widely used programming language in the world because of the widespread use of microcomputers. 

BASIC, or Beginners Algebraic Symbolic Instruction Code, was developed by Kemeny63 as a "baby FORTRAN" for simple computers (e.g., minicomputers). BASIC does not wait for the whole user-written program to be finished, but compiled each typed line as soon as typed. It was ideally suited for a simple learning environment. Microsoft VISUAL BASIC is a GUI-interfaced version. Microsoft QUICK BASIC 4.5 is much better than FORTRAN embodiments in accessing instruments for real-time data acquisition and control. 

BASIC (Beginner s All-Purpose Simplified Instruction Code) began as an interactive computer programming language especially easy to learn. Invented in 1964, it now exists in many widely different versions. Students learning programming for the first time may know BASIC as the simple language found on most personal computers. 

Fig. 4.3 The DMC meta-modeling architecture with platforms for computation (instruction set), object-orientation, and service-orientation. Each platform is shown as the instance of DMC triplet with corresponding executable item (exec code, object, service provider). The top layer of the architecture shows elements of service-oriented modeling. That complements exertion-oriented programming. The service platform manages the service providers (virtualization of service cloud —V3/V4 that are autonomically provisioned by the SOS on virtualized computation/object platforms (yHV2)...

Fig. 11.31 CAMPG/SYSQUAKE interface tmd instructions, top left. CAMPG environment control, bottom left. SYSQUAKE time and frequency response, top right. Bottom right, actual computer-generated code that CAMPG delivers so that SYSQUAKE can perform the simulation...

BASIC programming language (John Kemeny and Thomas Kurtz) Kemeny and Kurtz develop the BASIC computer programming language. BASIC is an acronym for Beginner s All-purpose Symbolic Instruction Code. 

Every computer has a word length that is characteristic of that machine. A computer s word length is usually determined by the size of its internal storage elements and interconnecting paths (referred to as buses), for example, a computer whose registers and buses can store and transfer 8 to 32 bits. The characteristic 8-bit field is referred to as a byte. Each operation that the processor can perform is identified by a unique binary number known as an instruction code or operation code (OP code). An 8-bit word used as an instruction code can distinguish among 256 alternative actions, more than adequate for most processors. 

By electronic engineering, a system of interconnected switching devices is able to respond in one of only two modes (on or off), and these modes can be controlled at the basic level of a bit. Bits are assembled into bytes, as with an 8-bit device, and through programming of the bytes a computer central processor can be made to follow sets of instructions (programs) written in special languages, either at a direct level (machine code) that can be acted upon immediately by a computer or at a high level that is translated for the user into machine code. 

This big increase in speed has not been without cost. The everyday machine codes and high-level languages (Fortran, Pascal, C, etc.) used to control operations in a standard computer are inappropriate for parallel processing, which needs its own instruction set and has led to the development of special languages for use with the transputer. 

Although much easier to assemble, a software program written in a high-level language requires more time for the computer to execute, since all the instructions must be translated into machine code before the computer can understand them. Even a simple statement like start in a high-level language requires several machine-code moves to execute. 

I am particularly indebted to Dr. Howard Lambert of Lawrence Livermore Laboratory and FfA Associates for providing the PC computer codes FTAP (fault ti ee code), POSTER (post processor), IMPORT (importance calculation), MONTE (Monte Carlo error determinadoni, and supporting documentation and instructions. 

Let us comment on the developed schematic Monte Carlo (MC) code. Of course there are many clever ways to improve the execution speed. There is the important concept of neighbor lists, of clever implementation of numerical instructions, and so on. In developing a computer simulation one usually plugs in these enhancing concepts bit by bit. 

In addition to these considerations, the report that is issued is also affected by the procedures that follow the actual analysis (post-analytical) including calculations and transcriptions. The use of computers, particularly in association with bar-coded sample containers, has improved the procedures of ensuring correct sample identity, the production of work lists and the presentation of results. Instructions relating to all the non-analytical aspects should be specified in the SOP associated with the analytical method. 

There are three phases to the development of a problem solution on a digital computer. First, the problem must be stated and the mathematical methods for its solution described. Second, the logical structure of the problem must be analyzed from the viewpoint of the calculator. Third, the program of actual machine instructions, in its prescribed coded form, must be written and tested. 

We close this section with one more note on careful nomenclature. A code renders a model into a set of instructions that can be understood by a digital computer. Thus, if one applies a particular model, let us say the molecular mechanics model called MM3 (which will be described in the next chapter) to a particular problem, say the energy of chair cyclohexane, the results should be completely independent of which code one employs to carry out the calculation. If two pieces of software (let s call them MyProg and YourProg) differ by more than the numerical noise that can arise because of different round-off conventions with different computer chips (or having set different tolerances for what constitutes a converged calculation) then one (or both ) of those pieces of software is incorrect. In colloquial tenns, there is a bug in the incorrect code(s). 

Source Code The human readable version of the list of instructions (programs) that enable a computer to perform a task. 

This is the lowest level of requirements decomposition. The technical design specification deliverable is translated into software source code. Source code is the human readable version of the list of instructions (programs) that enable a computer to perform a task. Source code is written in the programming language appropriate for the application to be generated. 

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