PYTHON

1. Installing Python

Python language was developed, in 1989, by Guido van Rossum , a Dutch developer. The name Python comes from the British television series Monty Python. In 2005, Guido was hired by Google to maintain and improve Python.

Python is used for general-purpose programming, and first released in 1991. It is an interpreted language, Python enables writing clear programs on both a small and large scale.

To install Python, go to :

https://www.python.org/downloads/ , and dowload the 2.7 version. Install in C:\ and set the path as: C:\Python27; a s I did.

Make a shortcut in the desktop and click on it..

The command line is :



Check an operation and quit ...

2. Some related definitions

2.1. A compiler

• A compiler is a computer program (or a set of programs) that transforms source code written in a programming language (the source language) into another computer language (the target language), with the latter often having a binary form known as object code.

The most common reason for converting source code is to create an executable program.

2.2. An interpreter

An interpreter is a program that most of its implementations executes instructions directly , line by line, without compiling them into a machine language program.

Php, Perl, Python, MATLAB, Caml, and Ruby are examples of interpreted languages.

Languages traditionally associated with compilation are Fortran, and C and C++. Some systems, such as Smalltalk, and Java may combine the two .

We can say also that the interpreter executes the program directly, translating each statement into a sequence of one or more subroutines already compiled into machine code.

The terms interpreted language and compiled language are not well defined because, in theory, any programming language can be either interpreted or compiled. In modern programming language implementation it is increasingly popular for a platform to provide both options.

An interpreted language is one where the instructions are not directly executed by the target machine, but instead read and executed by some other program (which normally is written in the language of the native machine).

The major advantage of compiled languages over interpreted languages is their execution speed. Because compiled languages are converted directly into machine code, they run significantly faster and more efficiently than interpreted languages.

In contrast to compiled languages, interpreted languages do not require machine code in order to execute the program; instead, interpreters will run through a program line by line and execute each command.

2.2. An Object-oriented program

Object-oriented programs manipulate collections of objects. Objects support methods. Smalltalk and Java are object-oriented languages. C++ and Python are languages that support object-oriented programming, but don’t force the use of object-oriented features.

2.4.Functional programming

Functional programming decomposes a problem into a set of functions.

2.5. Declarative languages

In declarative languages, we write a specification that describes the problem to be solved. Then the language implementation figures out how to perform the computation efficiently. SQL is ann example of a declarative language.

2.6. Procedural programming

Procedural programming is derived from structured programming, based upon the concept of the procedure call. Procedures, also known as routines, subroutines, or functions.

The major procedural programming languages include Fortran, ALGOL, COBOL and BASIC.