Python Tutorials for beginners

Python Tutorials for beginners 

1.   Introduction

Python is interpreted object-oriented language. It is also referred to as a high-level programming language. It is designed by Guido Van Rossum. It was initially released in the year 1991. The filename extensions are .py, .pyc, .pyd, .pyo. It enables the straight and easy programming for both small and large applications. Python uses expressions mainly similar to C language and its methods and typing. Python supports multiple programming paradigms like functional programming, imperative and procedural as well.

           Python can be more user-friendly because of its advantages.

1.      Applications:

              Python can be used to develop different applications like web applications, graphic user interface based applications, software development applications, scientific and numeric applications, network programming, Games and 3D applications and other business applications.

2.      Multiple Programming paradigms:

           Python is also used because of its providing continuous support to several programming paradigms. As it supports object-oriented programming and structured programming. Python has features, which also support various concepts of functional programming language. Python language features and programming paradigms allow you for developing the small as well as large applications.

3.      Robust Standard Library:

Python has a large and robust standard library to use for developing the applications. It also makes the developers use Python over other languages. While developing any web application, implementing web services, performing string operations and other usages like interface protocol, the standard library documentation helps.

4.      Code Readability:

             Python code is easy to read and maintained. The code should be of good quality and easy to maintain the source code and simplify the maintenance, which is required to develop the software application. It helps in building custom applications and clean code helps in maintaining and updating the software applications without putting extra effort on the same code. It is used for developing complex applications like scientific and numeric applications, and for both desktop and web applications. There are many open source applications of python frameworks, libraries, and development tools for developing the application without putting extra cost.

5.      Adopt Test Driven Development:

           Python makes coding easier as well as testing with the help of adopting Test Driven Development approach. Whenever the code development started, the written test cases can start testing the code simultaneously and provides the result.

6.      Other applications for which python is used:

There are other applications for which python is used that is Robotics, web scraping, scripting, artificial intelligence, data analysis, machine learning, face detection, color detection, 3D CAD applications, console-based applications, audio-based applications, video-based applications, enterprise applications, and applications for Images etc.

2.   Data Types

2.1       Variables:

Variables are containers for storing data values. Unlike other programming languages, Python has no command for declaring a variable.

A variable is created the moment you first assign a value to it. Python has the same rules for variable naming for example name can be started with _, A-Z, a -z, etc. some naming examples are number9, zero19,first_name,_lastname, etc. Python doesn’t have reserve words for datatype like Float, double, string and int.

2.2       Strings

String data types are used to store words or combinations of words having letters, numbers, special characters, etc. It can be stored by enclosing within single quotes and double quotes also.

     

Python doesn't support char data type it will create a string of character just by assigning character or number of characters:

     

·         Access values in String:

Python doesn't support Character data type. Square brackets are used to access substrings.

We can access a specific character or range of characters from a string.

By using ‘:‘we can also print the range of characters:

·        Updating String:

In python programming we can update or append string using plus + operator or by assigning new value but by assigning we will not access the old value. When we are trying to update the value we must keep in our minds that new value must be related to the previous value of the string meaning that they must have the same datatype.

·        Delete String: To delete the value of the string just deletes its object (reference variable):