# What Are Variables In Python?
# A variable is a memory location where you store a value.
# The value that you have stored may change in the future according to the specifications
# A Variable in python is created as soon as a value is assigned to it.
# It does not need any additional commands to declare a variable in python.
# Variable Definition & Declaration
x = 10
# Variable is declared as the value 10 is assigned to it.
# Rules when declaring variable
# 1. The variable name cannot start with a number.
# 2. It can only start with a character or an underscore.
# 3. Variables in python are case sensitive.
# 4. They can only contain alpha-numeric characters and underscores.
# 5. No special characters are allowed.
# Data Types In Python
# INTEGERS: are used to represent whole number values.
x = 100
y = 124
# it will be the integer as long as the value is a whole number.
# To check the type of any variable data type, we can use the type() function.
# It will return the type of the mentioned variable data type.
# FLOAT data type: is used to represent decimal point values.
x = 10.25
y = 12.30
# COMPLEX NUMBERS: are used to represent imaginary values.
# Imaginary values are denoted with ‘j’ at the end of the number.
x = 10 + 5j
# BOOLEAN: is used for categorical output, since the output of
# boolean is either true or false.
num = 5 > 4
#num is the boolean variable
type(num)
#the output will be bool
print(num)
#this will print true.
# Strings: in python are used to represent unicode character values.
# Python does not have a character data type,
# a single character is also considered as a string.
# We denote or declare the string values inside single quotes or double
# quotes. To access the values in a string,
# we use the indexes and square brackets.
name = 'edureka'
name[2]
#this will give you the output as 'u'
# Strings are immutable in nature, which means you cannot change a string
# once replaced.
# LIST: is ordered and changeable, unlike strings.
# We can add duplicate values as well. To declare a list we use the
# square brackets.
mylist = [10,20,30,40,20,30, 'edureka']
# SETS: set is a collection which is unordered,
# it does not have any indexes as well.
# To declare a set in python we use the curly brackets.
myset = {10, 20 , 30 ,40, 50, 50}
# TUPLES: is a collection which is unchangeable or immutable
mytuple = (10,10,20,30,40,50)
# DICTIONARY: is just like any other collection array in python.
# But they have key value pairs
mydictionary = { 'python': 'data science', 'machine learning' : 'tensorflow' , 'artificial intelligence': 'keras'}
mydictionary['machine learning']
#this will give the output as 'tensorflow'
mydictionary.get('python')
#this serves the same purpose to access the value.