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RPG II Programming language
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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.
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.
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.
12. Study these sample sections of programs. Rank them from 1 (easiest to understand) to 5 (most difficult to understand).
a) TABLE FILE SALES
SUM UNITS BY MONTH BY CUSTOMER
ON CUSTOMER SUBTOTAL PAGE BREAK END
b) 10101001
c) REPORT THE BASE SALARIES
BROKEN DOWN BY REGION FOR MANAGERS IN ENGLAND
d) e) A=0 X=1 INPUT Y FOR X=1 TO 3 A=Y**X PRINT A
| mov | ah, 3Dh |
| mov | al, 0 |
| push | cs |
| pop | ds |
13. Here is a list of language types used by programmers ranked from natural human language at the top to machine code at the bottom. Can you match any of the samples in previous task to this list?
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1 Natural language 4 Assembly language
2 Very high-level language 5 Machine code
3 High-level language
14. Study this fragment of a Basic program. What do you think this program is for?
| REM AVERAGES | |
| PRINT TYPE 999TO INDICATE END OF DATA- | |
| SUM = 0 | |
| PRINT 'PLEASE ENTER A NUMBER' | |
| DO WHILE NUMBER <>999 | |
| COUNTER = COUNTER + 1 | |
| INPUT NUMBER | |
| PRINT 'THE AVERAGE OFTHE NUMBERS IS:'; AVERAGE | |
15. Now listen to the recording to complete the missing lines in the program.
16. Study the completed program. It contains three faults. Can you find them?
17. Work in groups of three. Read two of the texts about computing languages and make notes in the table below. Then exchange information about the other texts with other students in your group.
С++ was developed from the С language. It was designed as a systems programming language with features that make it easy to control the computer hardware efficiently. It was used to produce the Microsoft Windows operating system. It is portable, i.e. programs written in С++ can be easily adapted for use on many different types of computer systems.
HTML stands for HyperText Markup Language. It is a page description language used for creating webpages. HTML uses a system of tags to mark page links and formatting. For example, the tag <u> tells the program to start underlining a text. Although programs cannot be created using HTML, small programs can be embedded in HTML code using a scripting language like JavaScript.
Java is a programming language originally designed for programming small electronic devices such as mobile phones. It can run unchanged on any operating system that has a Java Interpreter program. Java is used for writing programs for the World Wide Web.
JavaScript is a scripting language. It is powerful and easy to use. Scripts are small programs that can be used to perform simple tasks or tie other programs together. JavaScript is designed for use inside webpages. It can enable a webpage to respond to a mouse click or input on a form. It can also provide a way of moving through webpages and produce simple animation.
Visual Basic is a programming environment, not simply a language. It uses the language BASIC, a simple language developed to make it easy for people to learn how to program. Visual Basic has predefined objects such as dialog boxes, buttons, and text boxes which can be chosen from a toolbox and dragged across the screen using the mouse and dropped into the required position. BASIC programming code is attached to form a complete program. Visual Basic is used to write general purpose applications for the Windows operating system.
Delphi is similar to Visual Basic. It is also a programming environment for developing programs for the Windows operating system. It has predefined objects that can be chosen from a toolbox. In Delphi, however, the code attached to the objects is written in a form of Pascal. You can think of Delphi as a kind of 'Visual Pascal'. Like Visual Basic, it is often used for general purpose programs.
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| Language | Associated language | Type of language | Use |
| C++ | |||
| HTML | |||
| Java | |||
| Java Script | |||
| Visual Basic | |||
| Delphi |
18. Now read the texts again and answer these questions about special features of the languages.
1. Which language uses a system of tags?
2. Which languages are designed to be used inside webpages?
3. Which language was used to write the Windows operating system?
4. What is a 'portable' language?
5. Which language can have small programs embedded in it using JavaScript?
6. What does HTML stand for?
7. Which languages can only be used in the Windows operating system?
8. Which language cannot be used for writing programs?
19. Using the information in the reading texts and the table in Task 6, decide which languages would be best for these users and tasks.
1. A language for school pupils learning to program for the first time.
2. A language for professional programmers who want their software to run on any type of computer system.
3. A language for a student who wants to create her own webpage.
4. A language for a website designer who wants to include simple animation in a site.
5. A language for computing students who want to write a general purpose program as a college project.
20. Look back at the notes you made in the table in Task 6. Write a brief summary of the reading texts based on your notes.
| Associated | Type of | ||
| Language | Language | Language | Use |
| С++ | С | Programming | General and systems programming |
| . |
Example: С++ is a programming language. It is used for general and systems
programming.
21. Speak about programming languages.
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