Introduction to Python

In this I will try to cover basics of python which is required for Data Science.

What is Python?

• Python is a very general purpose programming language, which means it has wide variety of applications.
• It can be used in web development, Mobile Applications, Machine Learning, Data Mining etc.

Why Python?

• If you ask any person who knows python all of them will tell that its the easiest language to learn and code.
• You can code in python like writing steps in english or any language.
• Its very to easy to interpret.
• Line of codes require to run a program is less compare to other programming languages. This we can encounter below when we run our 1st program

1st Program in Python - Hello World

Python is Case Sensitive means Print and print have different meaning in python. So If i write Z=1 and z=2 it will not overide the variables but store two different values in each.

Variables

• Variable is used to store values in python.
• Syntax : Variable_name = "Value". = is used an assignment operator.
• Variable names can consist of any characters or alphabets. They can have alphanumeric or special characters in them.
• Variable names cannot start with number or special characters except the _ (Underscore).

• Try to keep variables in plain and simple language so its easy to understand what values they represent.
• Avoid using variables which are similar to the attributes or function in the in-built libraries.

Operators

Types of Operators in Python

• Arithmetic Operators (For Basic calculation Purpose)
  • '*' --> Multiplication
  • '/'--> Division
  • '+' --> Addition
  • '-'-- > Subtraction
  • '%' --> Modulous

• Comparison Operator (For Comparing two variables and constants)
  • Less than '<'
  • greater than '>'
  • Equal to '=='
  • Less than or equal to '<='
  • Greater than or equal to '>='
  • Not equal to '!='

• Logical Operator (Used for Logical conditions)
  • And
  • Or
  • Not

• Bitwise Operator (Used to compare binary numbers i.e numbers which are represented in 0 and 1)
  • Bitwise And '&' - Set each bit to 1 if both bits are 1 eg: 1001 & 1010 will give --> 1000
  • Bitwise OR '|' - Set each bit to 1 if one of the bits is 1 eg: 1001 | 1010 will give --> 1011
  • Bitwise XOR '^' - Set each bit to 1 if only one of the bits is 1 eg: 1001 ^ 1010 will give --> 0011
  • Left shift '<<' - shift left by inserting zeroes from left and right most digit is removed eg: 1001 **<<**2 will give --> 0010
  • Right shift '>>' - shift rigth by inserting zeroes from right and left most digit is removed eg: 1011 **>>**2 will give --> 1100

• Identity Operator (For checking the identity of constants and variables)
  • is - returns true if the objects are similar
  • is not - returns true if the objects are not similar

• Membership Operator (For finding relations between two variables)
  • in - Returns true if the value is present in the object
  • not in - Returns true if the value is not present in the object

Data Types

• The most important thing in any code is data types. These are objects used to store some kind of information.

• Each data types can store only certain type of data.

• Basic Types of Data

  • int - This data type is used to store only numerical or Integers and non decimal values
  • Float - This data type is used to store only Decimal or floating values.
  • Bool - This data type is used to store only Boolean data (true or false)
  • Str - This data type is used to store only Strings which can be alphanumeric and consist of any special characters.
  • complex - Numbers with real and imaginary part such as 3+2j where j is square root of -1

• type("xxx") is used to get the information about type of data for that particular object

• This repository covers the basic of pythons now we will level up a little and explore more in depth of python.
• Below are the list of other respository for learning each concept
• Data Structures
• Conditional Statements
• Functions
• OOPS