Unit 4. COMPUTER PROGRAMMING

1. Ознакомьтесь с терминами текста 1.

1. 
   equation — уравнение, приравнивание
   
2. 
   list of instructions — перечень команд
   
3. 
   guard — защищать; предохранять; завершать; за­канчивать
   
4. 
   appropriate sequence — необходимая (требуемая) последовательность
   
5. 
   program logic — логическая последовательность выпол­нения программы
   
6. 
   flowchart — блок-схема; составлять блок-схе­му
   
7. 
   flowcharting — построение блок-схемы
   
8. 
   pictorial representation — наглядное представление
   
9. 
   predefined symbols — заранее задан­ные символы
   
10. 
    specifics — специальные черты; характерные особенности
    
11. 
    emplate — шаблон; маска; образец; эталон
    
12. 
    pseudocode — псевдокод; псевдопро­грамма
    
13. 
    burden — издержки; затраты
    
14. 
    programming rules — правила программирования
    
15. 
    consume — потреблять; расходовать
    
16. 
    emphasize — выделять; подчеркивать
    
17. 
    top-down approach — принцип нисходящей разработки
    
18. 
    looping logic — логическая схема выполнения (опера­ций) в цикле
    

2. Прочтите текст и объясните, как вы понимаете термин «компьютерное программирование».

Text 1. COMPUTER PROGRAMMING

Programming is the process of preparing a set of coded in­structions which enables the computer to solve specific prob­lems or to perform specific functions. The essence of computer programming is the encoding of the program for the computer by means of algorythms. The thing is that any problem is ex­pressed in mathematical terms, it contains formulae, equations and calculations. But the computer cannot manipulate formu­lae, equations and calculations. Any problem must be specially processed for the computer to understand if it is coded or programmed.

The phase in which the system's computer programs are written is called the development phase. The programs are lists of instructions that will be followed by the control unit of the central processing unit (CPU). The instructions of the program must be complete and in the appropriate sequence, or else the wrong answers will result. To guard against these errors in logic and to document the program's logical approach, logic plans should be developed.

There are two common techniques for planning the logic of a program. The first technique is flowcharting. A flowchart is a plan in the form of a graphic or pictorial representation that uses predefined symbols to illustrate the program logic. It is, there­fore, a "picture" of the logical steps to be performed by the computer. Each of the predefined symbol shapes stands for a general operation. The symbol shape communicates the nature of the general operation, and the specifics are written within the symbol. A plastic or metal guide called a template is used to make drawing the symbols easier.

The second technique for planning program logic is called pseudocode. Pseudocode is an imitation of actual program in­structions. It allows a program-like structure without the bur­den of programming rules to follow. Pseudocode is less time-consuming for the professional programmer than is flowcharting. It also emphasizes a top-down approach to program structure.

Pseudocode has three basic structures: sequence, decision, and looping logic. With these three structures, any required logic can be expressed.

3. Просмотрите текст еще раз и ответьте на вопросы, ис­пользуя информацию текста.

1. What is programming? 2. What is the essence of program­ming? 3. What should be done with the problem before process­ing by the computer? 4. What is a program? 5. What are instruc­tions? 6. What are the main techniques for planning the program logic? 7. What is a flowchart? 8. What is a template and what is it used for? 9. What do you understand by "pseudocode"? 10. What are the basic structures of pseudocode?

4. Найдите в тексте английские эквиваленты следующих словосочетаний:

Совокупность закодированных команд; суть компьютер­ного программирования; кодирование посредством алгорит­ма; формулы, уравнения, вычисления; обработать особым образом; перечень команд; необходимая последователь­ность; защищать от ошибок; составлять план логической последовательности; общепринятая методика; логическая последовательность выполнения программы; построение блок-схемы; наглядное представление; заранее заданные символы; шаблон; псевдопрограмма; без издержек; выде­лять принцип нисходящей обработки; расходовать меньше времени; логическая схема выполнения операций в цикле; необходимая последовательность операций.

5. Подберите из предложенных ниже русских словосоче­таний значения следующих терминов на английском языке:

Program: access program; application program; archived program; binary program; common program; compatible / in­compatible program; control / management program; database program; debugging program; educational / teaching / training program; free program; general-purpose program; high-perfor­mance program; off-line program; on-line program; operating (-system) program; processing program; protected-mode pro­gram; remote program; running program; self-loading program simulation program; support program; utility program; virus-detection program; watch-dog program.

Программа в двоичном коде; прикладная программа; (не) совместимая программа; бесплатная программа; про­грамма отладки; сторожевая программа; дистанционная программа; программа моделирования; сервисная про­грамма; вспомогательная программа; программа для дос­тупа (к данным); заархивированная программа; програм­ма, работающая с базой данных; обучающая программа; программа, выполняемая с большой скоростью; универ­сальная программа; программа, выполняемая в защищен­ном режиме; программа обработки данных; программа операционной системы (системная программа); выполня­емая программа; сетевая /несетевая программа; самоза­гружающаяся программа; часто используемая (распростра­ненная) программа; программа управления; программа обнаружения вирусов.

6. Переведите предложения, содержащие сослагательное наклонение.

1. I should like to be a top specialist in computer technolo­gy. 2. It is necessary that the program should be debugged (отлажена) by a programmer. 3. It is required that the program­mer should code the instructions of the program in the appro­priate sequence. 4. The manager demanded that the work should be performed in time. 5. Write down the algorythm of comput­er operations lest you should make errors. 6. Our teacher speaks English as if he were a real Englishman. 7. Without the Sun there would be no light, no heat, no energy of any kind. 8. I wish it were summer now and we could go to the seaside. 9. American scientists suggested that the quantum generator should be called laser, which is the acronym for light amplification by stimulat­ed emission of radiation. 10.1 wished you had mentioned these facts while the subject was being discussed.

7. Ознакомьтесь с терминами текста 2.

1. 
   programming language — язык программирования
   
2. 
   coded form — кодированный вид; кодированное пред­ставление
   
3. 
   to convey — передавать; сообщать
   
4. 
   to improve — улучшать, совершенствовать machine-oriented language — машинно-ориентирован­ный язык
   
5. 
   business-oriented language — язык для (программирова­ния) экономических задач
   
6. 
   problem-oriented language — проблемно-ориентирован­ный язык
   
7. 
   string of binary — строка двоичного представления data handling — обработка данных; работа с данными
   
8. 
   field-name length — длина имени поля
   
9. 
   incorporate features — включать свойства, особенности
   
10. 
    versatile — многофункциональный; разносторонний; универсальный
    
11. 
    generous — большой, значительный (о количестве)
    
12. 
    mathematical relationship — математическая связь (соот­ношение)
    

8. Прочтите текст и объясните, что представляют собой языки программирования.

Text 2. PROGRAMMING LANGUAGES

Let's assume that we have studied the problem, designed a logical plan (our flowchart or pseudocode), and are now ready to write the program instructions. The process of writing pro­gram instructions is called coding. The instructions will be writ­ten on a form called a coding form. The instructions we write will be recorded in a machine-readable form using a keypunch, key-to-tape, or key-to-disk, or entered directly into computer memory through a terminal keyboard.

The computer cannot understand instructions written in just any old way. The instructions must be written according to a set of rules. These rules are the foundation of a programming lan­guage. A programming language must convey the logical steps of the program plan in such a way that the control unit of the CPU can interpret and follow the instructions. Programming languages have improved throughout the years, just as comput­er hardware has improved. They have progressed from machine-oriented languages that use strings of binary Is and 0s to prob­lem-oriented languages that use common mathematical and/or English terms.

There are over 200 problem-oriented languages. The most common of them are COBOL, FORTRAN, PL/I, RPG, BA­SIC, PASCAL.

COBOL

COBOL was the most widely used business-oriented pro­gramming language. Its name is an acronym for Common Busi­ness-Oriented language. COBOL was designed to solve prob­lems that are oriented toward data handling and input-output operations. Of course, COBOL can perform arithmetic opera­tions as well, but its greatest flexibility is in data handling. CO­BOL also was designed as a self-documenting language. Self-documenting languages are those that do not require a great deal of explanation in order to be understood by someone reading the program instructions. The self-documenting aspect of CO­BOL is made possible by its sentence like structure and the very generous maximum symbolic field-name length of 30 charac­ters. With a field-name length of up to 30 characters, the name can clearly identify the field and its purpose.

FORTRAN IV

The FORTRAN IV language is oriented toward solving prob­lems of a mathematical nature. The name FORTRAN comes from the combination of the words formula translation. The version of FORTRAN IV has been designed as algebra-based programming language. Any formula or those mathematical reialionships that can be expressed algebraically can easily be expressed as a FORTRAN instruction. FORTRAN is the most commonly used language for scientific applications.

PL/I

PL/I stands for programming language I. It was designed as a general-purpose language incorporating features similar to COBOL for data handling instructions and features similar to FORTRAN for mathematical instructions. PL/I is much more than a combination of the good features of both COBOL and FORTRAN, as it has many capabilities that are unique. Yet, although PL/I is one of the most versatile and the most power­ful of the programming languages, it is not the most commonly used. COBOL and FORTRAN have been available for a longer period of time than PL/I, and many more users work with those languages.

9. Просмотрите текст еще раз и ответьте на вопросы, ис­пользуя информацию текста.

1. What is the process of writing instructions called? 2. What is a code? 3. How must instructions be written? 4. What is the foundation of any programming language? 5. How was the de­velopment of programming languages progressing throughout the years? 6. What are the most common problem-oriented lan­guages? 7. What is COBOL? 8. What functions was COBOL designed for? 9. What does FORTRAN serve for? 10. What ca­pabilities does PL/I have?

10. Найдите в тексте английские эквиваленты следующих словосочетаний:

Языки программирования; блок-схема; кодированная форма; вид, удобочитаемый для компьютера; в соответ­ствии с набором правил; представить логические шаги программы; таким образом; совершенствовать языки про­граммирования; машинно-ориентированные языки; про­блемно-ориентирован-ные языки; обычный термин; язык для программирования экономических задач; обработка информации; операции по вводу-выводу данных; гиб­кость; идентифицировать поле и его цели; решение проблем математического характера; сферы научного применения; универсальный язык; включать свойства; уникальные воз­можности; многофункциональный и самый мощный из языков программирования.

11. Найдите в текстах 1 и 2 слова, близкие по значению следующим:

Nouns: command; line; characteristic; form; evolution; enu­meration; mistake; method; character; manual (instruction); consumption; storage; basics; abbreviation; interpretation; cor­relation; possibility.

Verbs: include; inform; process; protect; apply; permit; stress; suppose; learn; make up; write; key; explain; define; perfect; advance; decide; execute; demand.

Adjectives: full; incorrect; usual; necessary; accessible; re­quired; considerable; floppy; possible.

12. Переведите условные сложноподчиненные предложе­ния. Обратите внимание на форму выражения разных типов условия.

I. 1. If you try very hard you can master any language. 2. If you want to master any language you must know at least three thousand words. 3. You will improve your pronunciation if you read aloud every day. 4. Time will be saved if one uses a com­puter. 5. If you learn all the words of the lesson you will write your test successfully. 6. If you or I add up two numbers of six figures without a calculator, it will take us a lot of time.

II. 1. It would be a good thing if you didn't smoke. 2. If the earth didn't rotate it wouldn't have the shape of a ball. 3. If I had the time I should help you to solve the problem. But I must be off. 4.1 should translate the article without difficulty if I knew English well. 5. If I were in your place I should learn to speak English fluently. 6. Were you asked to explain why addition is performed the way it is, you would probably have to think for a while before answering.

III. 1. 1 decided to stay at home last night. I would have gone out if I hadn't been so tired. 2. Had he not been busy, he wouldn't have missed that conference. 3. Why didn't you phone me yesterday? I would have helped you. 4. If you had attended preliminary courses, you would have passed you examinations, more successfully. 5. Had the manager had this information before, he would have acted differently. 6. The binary system is particularly appropriate to the nature of an electric machine; if it had not existed, computer designers would have had to invent it.

13. Выполните перевод следующих текстов письменно по вариантам.

1. RPG II Programming language

RPG II is a business-oriented language. The name stands for report program generator. RPG is considerably different from other programming languages. RPG is, in effect, a large prewrit­ten program. The programmer simply indicates the options within the master program that are to be used and, through a set of indicators, when they are to be used.

RPG was originally referred to as a "quick-and-dirty" pro­gramming language. That is, it is quick for the programmer to write and relatively inefficient in its use of main storage and processing speed. The latest version of RPG, called RPG II, greatly improved the language and gave it additional capabili­ties. RPG has an advantage over COBOL in that it requires less training for a programmer to become proficient in it. For this reason, RPG is commonly used on many smaller computers and in small business.

2. BASIC

BASIC is the acronym for beginner's all-purpose symbolic instruction code. It was developed in Dartmouth College as an easy-to-learn programming language for students and inexpe­rienced programmers. Its key design goal is simplicity. BASIC has become a very popular language in systems where many users share the use of a computer through terminals and it has become a universal language for personal computers.

The language BASIC is mathematically oriented, that is, its typical use is to solve problems of a mathematical nature. Be­cause BASIC programs are usually executed from a terminal or microcomputer where input is entered through a keyboard and printed output is relatively slow, problems of a business nature requiring large volumes of input-output data are usually not practical.

3. PASCAL

PASCAL was invented in 1970 by Professor Niklaus Wirth of Zurich, Switzerland. It was named after the mathematician Blaise Pascal, who invented one of the earliest practical calcu­lators. PASCAL is a mathematically oriented programming lan­guage and, as such, is most commonly used in mathematics, engineering, and computer science departments of colleges and universities. This language is somewhat unusual in that it was designed to be a structured language. This means that the pro­gram must be written in logical modules which are in turn called by a main controlling module. Much of PASCAL'S popularity is due to work done at the University of California at San Di­ego, where PASCAL has been implemented on several differ­ent computers including microcomputers.

14. Прочтите тексты (по вариантам) и составьте рефера­ты на английском языке.

1. The conversion of symbolic languages

As we see, most of the symbolic languages are oriented to­ward the particular application areas of business or science (math). The one problem with all symbolic languages is that none of them can be understood by a computer. The symbolic languages may say AP, ADD, or us6 a "plus" sign to indicate an addition step, but the only thing that means addition to a computer is its binary machine code. We have symbolic pro­grams that are relatively easy for humans to understand, but they cannot be understood by computers. On the other hand, we have machine code that is understood by the computer, but it is dif­ficult for humans to use. The solution is a translator that trans­lates the symbolic program into machine code. The translator allows the human to work with relatively easy-to-understand symbolic languages and it allows the computer to follow instruc­tions in machine code. The translation of symbolic instructions to machine code is accomplished through the use of a program called a language processor. There are three types of language processors. They are called assemblers, compilers, and interpret­ers. Each translates symbolic instructions to machine code, but each does it differently.

(The translator is a program itself. It is part of a group of programs, called the operating systems, that help us to use the computer.)

2. Running the computer program

The operating system is a collection of program provided by the computer's manufacturer that allows us to schedule jobs for the computer, to translate source programs into object programs, to sort data stored on secondary storage devices, and to copy data from any input device to any output device. These programs are called control programs, language programs and utility pro­grams.

The control program (often called the supervisor, monitor, or executive) is a main-storage-resident program. Its functions are to schedule jobs, scheduled input and output for our programs and to monitor the execution of our programs.

The language processors are programs that translate source programs into object programs. There are three types of language processors: assemblers, compilers, and interpreters. Each lan­guage has its own language processor.

The service programs are programs that are commonly used in all data processing centers. They have functions that are re­quired by everyone using a computer. Examples of service pro­grams include linkage editors to prepare object programs for execution, a librarian to catalog programs into a library area on magnetic disc, utility programs to transfer data from device to device, and sort-merge programs for sorting data on magnetic tape or disk.

3. Testing the computer program

There are two kinds of errors or bugs with which program­mers must deal. The first type is the coding error. Such errors are syntax errors that prevent the language processor from suc­cessfully translating the source program to object program code. The language processor identifies the nature and the location of the error on the source program listing, so these errors are relatively easy to find and correct. The second type of bug is the logic error. The computer program can be successfully translat­ed, but the program does not produce the desired results. These errors are generally much more difficult to find and to correct than are coding errors. Logic errors can be avoided through careful planning of the program logic, but it is the programmer's responsibility to test thoroughly all of the program's functions, in order to verify that the program performs according to spec­ifications.

There are many tools provided to the programmer to help in debugging the program logic. These tools are called debug packages or tracing routines. They assist the programmer in fol­lowing the logic by printing out calculation results and field values used in making logic decisions in the program. In a few cases it may be necessary to use a memory dump — a printout of the instructions and date held in the computer's memory — in order to find the cause of logic errors.
Final Test

1. Подберите вместо пропусков подходящее по смыслу слово.

1. The most common ______ for planning the program logic are flowcharting and pseudocode.

a) technologies; b) technics; c) techniques.

2. ______ was designed for dealing with the complicated mathematical calculations of scientists and engineers.

a) COBOL; b) FORTRAN; c) PL/I.

3. ______ is the foundation of any programming languages.

a) a set of rules; b) a group of numbers; c) a lot of in­structions

4. I / О______match the physical and electrical charac­teristics of input-output devices.

a) interchanges; b) interfaces; c) interpretations

5. Letter-quality, dot-matrix and ink-jet printers are all ______ printers.

a) line; b) page; c) character.

6. The most common device used to transfer information from the user to the computer is the______.

a) keyboard; b) printer; c) modem.

7. Input-output units link the computer to its external.

a) requirement; b) development; c) environment.

8. I / О devices can be classified according to their speed, visual displays being _______ devices.

a) high-speed; b)medium-speed; c) low-speed.

2. Согласуйте слова в левой колонке с их интерпретаци­ей, предложенной справа.

1. Computer a) an electronic device accepting data processing results from the computer sys­tem;

2. Input b) the unit performing arithmetic opera­tions called for in the instructions;

3. Output c) the unit coordinating all the activities of various components of the computer. It reads information, interprets instruc­tions, performs operations, etc;

4.Software d) a set of programs designed to control the operation of a computer

5.Hardware e) lists of instructions followed by the con­trol unit of the CPU:

6. Storage f) an electronic device keying information into the computer;

7.CPU g) the unit holding all data to be processed, intermediate and final results of process­ing;

8.CU h) visible units, physical components of a data processing system;

9.ALU i) the unit that directs the sequence of sys­tem operations, selects instructions and interprets them;

10.Program j) a device with a complex network of elec­tronic circuits that can process informa­tion, make decisions, and replace people in routine tasks.

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