Learning Computer Programming

Learning Computer Programming

In everyday life, to communicate with others, we should use the same language as the person. If we use the Indonesian language, our speaker must understand Indonesian. What happens if it turns out the other person we do not understand Indonesian? There are two paths that can be taken: first, by using the services of a translator or both, the employed under a language understood by our speaker.

The above illustration provides a description similar to those seen in computer programming. To be able to communicate with the computer, then steps must be taken is to master the language understood by computers. Computers, in essence, is a digital machine that only knows the condition of no current and no electric current (usually symbolized number 1) and no electric current (usually symbolized the number 0). From the condition of the machine is exactly the known languages, the languages ​​recognized by the computer by using a password 1 (one) and 0 (zero). Programming with machine language usually classified in a lower level language (low level languages).

Because the machine language is very difficult, then came the idea to symbolize the password string of 1's and 0 with abbreviations that are easier to understand humans. This word stands for then called mnemonic code. The programming language using abbreviations (mnemonic code) is assembly language. Assembly language uses software to translate / convert commands into machine language assembly called an assembler. Assembly language is a mid-level programming language (intermediate level languages).

Examples:

Machine language, the Intel processors? 0011 1010 0000 1011.

Assembly language? CMP AL, 0D (Compare AL with 0D)

It can be seen that the abbreviation CMP AL, 0D lebh far easier to understand than

by 0011 1010 0000 1011.

Assembly programming language felt it was too difficult then developed a programming language that is more user friendly. Programming language that uses words that are easily understood by humans. Pemgraman language like this are known as third-generation language or abbreviated 3GL (third-generation language). Additionally known as the 3GL, also known as high-level language or HLL (high level languages).

Programming language to use software to convert the program into human language into assembly language or machine language, which consists of two types of interpreters and compilers.

Interpreter translates the program line by line, meaning that if a line to be executed, then the line is first translated into machine language, only then the next line to be executed. Examples of programming languages ​​using the interpreter is Basic.

The compiler translates all commands in machine language and then run the result of translation. The translation results are stored in a file or memory. Examples of languages ​​that use the compiler is Pascal, C, and C ++. The development of the programming language does not stop until the third gene only. There is a next generation, which is a fourth-generation language or abbreviated 4GL (fourth generation languages). Fourth generation language is commonly used in database applications. It is also used mainly in object-oriented programs include Visual C, Visual Basic, Delphi, and Visual Fox Pro, and many more.

Technology

PROGRAMMING STRUCTURED

The idea of ​​structured programming was first proposed by Professor Edsger Djikstra from Eindhoven University around 1965. In the paper, the proposed elimination of the command GOTO Djikstra on structured programming. Unlike the HD Millis opinion which revealed that structured programming does not depend on whether there is a GOTO but rather the structure of the program itself. From the statements of both, gives no clear definition for structured programming. But it can be underlined that the structured programming is a process to implement the sequence of steps to solve a problem in the form of a program.

The goal of structured programming are:

(1) improve the reliability of a program,

(2) The program is easy to read and traced,

(3) simplify the complexity of the program,

(4) maintenance program, and

(5) improve programming productivity.

Structured programming is characterized by:

(1) contains the proper technique and the correct solution,

(2) have problem-solving algorithm is simple, standard and effective,

(3) has a logical structure that is correct and easy to understand,

(4) consists of three basic structures that sequence, selection and iteration,

(5) avoids the use of GOTO,

(6) lower testing costs,

(7) has good documentation,

(8) the cost of care and lower the required documentation.

Steps to create a good and structured programs are:

1. Defining the Problem

Is an important and vital step that is most often skipped by many programmers. Because of the critical importance of defining this problem it is advisable to first define the problem to be solved, any insert should be given and how outputs.

2. Determine Solutions

Once the problem is clearly defined, the inputs to be provided and the desired output is also already known next is to find a way how to solve these problems with entries already known. If the problem is too complex, can be divided into small modules miraculous. For example, a program to calculate the inverse matrix. The first module is requesting input square matrix. The second module is to find the inverse of a matrix that has been inserted, and the last module is displaying the results to the user.

3. Selecting Algorithms

The algorithm is a finite sequence of steps to solve the problem of logic or mathematics. Selection algorithm is a vital step, because a mistake choosing the algorithm will cause the program will give poor performance.

4. Writing Program

To write a program to consider the language used and the need or problem to be solved problems. Any language can be used, taking into account the effectiveness and efficiency as well as cost.

5. Testing Program

If a program has been written, it must be tested. Initial testing in the form of a compilation of the test program grammar and truth. The next needs to be examined whether the program is already showing output as desired or not. Furthermore, it must be tested program with many other cases. Often there is a program running in case of A, B and C but is not running for the case of X, Y, and Z. This test should be conducted until absolutely sure the program has been running well.

6. Writing Documentation

Writing documentation is done in line with the manufacturing program. Documentation is very important for the development and improvement of the program so that the program can always be renewed.

7. Caring Program

Nursing program aims to detect bugs that were previously undetectable. Or it could be use to add new facilities in the program, so the need for revisions to the program.

PASCAL programming language

Pascal is a high-level language oriented to any destination. Pascal was designed by Prof. Niklaus Wirth of Techival University in Zurich, Switzerland, while Pascal name is taken from a mathematician Blaise Pascal and philosophi famous in the 17th century coming from France.

Pascal was first published in 1971 with the aim to systematically teach computers. Because it is a structured programming, then in a short time has become the Pascal programming language popular. Pascal has a variety of compiler used, among others, Turbo Pascal, GNU Pascal, Free Pascal, UCSD Pascal and Apple Pascal. In the discussion of this book the author uses the Free Pascal Compiler (FPC) version 2.0.2.

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