print()

- This command is used to show something as output.

Example :

Code :

print("Hello world")
Output :

Hello world

Comment

Comments can be used to explain Python code, to make the code more readable, to prevent execution when testing code.
Comments starts with a #, and Python will ignore them.

Example :

Code :

print("Hello world") #Here we printed Hello world using the print function.

Output :

Hello world

Note: Comments can be placed at the end of a line, and Python will ignore the rest of the line. A comment does not have to be text that explains the code, it can also be used to prevent Python from executing code.

Code :

print("Hello pikachu") #print("Hello Arcues")

Output :

Hello pikachu

Variable

- Generally, we know that many things change around us. Like, Climate,Your age,Your bank balance, etc.
In maths, we use x & y as variables if we don't know the accurate number.The same thing is applied in the programming too.

Example:
var_name = 151
any_name = "NEAN PROGRAMMING"

The name of the variable must always start with either a letter or an underscore (_). For example: _str, str, num, _num are all valid name for the variables. The name of the variable cannot start with a number. For example: 5num is not a valid variable name.

Note: Variable names are case-sensitive (page, Page and PAGE are three different variables)

Example :

Code :

x = 10 y = 20 z = x + y print(z)

Output :

30

We can store any text too.


Code:

first_name = "Sasuke" last_name = "Uchiha" print(fisrt_name," ",last_name)

Output :

Sasuke Uchiha

If you want to specify the data type of a variable, this can be done with casting.

Example :

Code :

x = str(3) # x will be '3' y = int(3) # y will be 3 z = float(3) # z will be 3.0)

You can get the data type of a variable with the type() function.

Example :

Code :

x = 7 y = "Cat" print(type(x)) print(type(y))

Note: String variables can be declared either by using single or double quotes

Python allows you to assign values to multiple variables in one line.

Example :

Code :

x, y, z = "Cat", "Dog", "Mouse" print(x) print(y) print(z)

Output :

Cat Dog Mouse

Data types

In programming, data type is an important concept.
Variables can store data of different types, and different types can do different things. Python has the following data types built-in by default, in these categories:

Text Type:	str
Numeric Types:	int, float, complex
Sequence Types:	list, tuple, range
Mapping Type:	dict
Set Types:	set, frozenset
Boolean Type:	bool
Binary Types:	bytes, bytearray, memoryview
None Type:	NoneType

Python Numbers

There are three numeric types in Python:

1.int
2.float
3.complex

Variables of numeric types are created when you assign a value to them.

Python Strings

Strings in python are surrounded by either single quotation marks, or double quotation marks.
'hello' is the same as "hello".

You can assign a multiline string to a variable by using three quotes.

Example :

Code :

print(""" The cat is a domestic species of small carnivorous mammal. It is the only domesticated species in the family Felidae and is often referred to as the domestic cat to distinguish it from the wild members of the famil""")

The upper() method returns the string in upper case:

Example :

Code :

a = "Hello, World!" print(a.upper())

Output :

HELLO WORLD!

The lower() method returns the string in lower case:

Example :

Code :

a = "Hello, World!" print(a.lower())

Output :

hello world!

The replace() method replaces a string with another string

Example :

Code :

a = "Hello, World!" print(a.replace("H","J"))

Output :

Jello, World!

List

Lists are used to store multiple items in a single variable.
Lists are one of 4 built-in data types in Python used to store collections of data, the other 3 are Tuple, Set, and Dictionary, all with different qualities and usage.
Lists are created using square brackets:

List is a collection which is ordered and changeable. Allows duplicate members.
Tuple is a collection which is ordered and unchangeable. Allows duplicate members.
Set is a collection which is unordered, unchangeable*, and unindexed. No duplicate members.
Dictionary is a collection which is ordered** and changeable. No duplicate members.

*Set items are unchangeable, but you can remove and/or add items whenever you like.
**As of Python version 3.7, dictionaries are ordered. In Python 3.6 and earlier, dictionaries are unordered.

Code :

animal_list = ["dog", "mouse", "cat"] print(animal_list)
Output :

"dog", "mouse", "cat"

List items are ordered, changeable, and allow duplicate values. List items are indexed, the first item has index [0], the second item has index [1], the third item has index [2], the fourth item has index [3] etc.

Example :

Code :

animal_list = ["dog", "mouse", "cat"] print(animal_list[0]) print(animal_list[2])
Output :

dog cat

Note: A list can contain different data types:
list1 = ["nean", 151, True, 100, "cat"]

input

In Python, we use input() function to take input from the user. Whatever you enter as input, the input function converts it into a string. If you enter an integer value still input() function convert it into a string.

Example :

Code :

#Taking input from user name=input() #showing output print(name)

Output :

pikachu

Code :

#Taking input from user with message name=input("Enter your name: ") #showing output print("Your name is ",name)

Output :

Enter your name: pikachu Your name is pikachu

Casting

There may be times when you want to specify a type on to a variable. This can be done with casting.

Casting in python is therefore done using constructor functions:

int() - constructs an integer number from an integer literal, a float literal (by removing all decimals), or a string literal (providing the string represents a whole number)
float() - constructs a float number from an integer literal, a float literal or a string literal (providing the string represents a float or an integer)
str() - constructs a string from a wide variety of data types, including strings, integer literals and float literals

Example :

Code :

x = int(1) # x will be 1 y = int(2.8) # y will be 2 z = int("3") # z will be 3

x = float(1) # x will be 1.0 y = float(2.8) # y will be 2.8 z = float("3") # z will be 3.0 w = float("4.2") # w will be 4.2

x = str("s1") # x will be 's1' y = str(2) # y will be '2' z = str(3.0) # z will be '3.0'

num = int(input("Enter your number: ")) #Given number will be integer print(num)

Conditions if-elif-else

Conditions and If statements

Python supports the usual logical conditions from mathematics:

Equals: a == b

Not Equals: a != b

Less than: a < b

Less than or equal to: a <= b

Greater than: a > b

Greater than or equal to: a >= b

These conditions can be used in several ways, most commonly in "if statements" and loops. An "if statement" is written by using the if keyword.

Example :

Code :

a = 100 b = 151 if b > a: print("b is greater than a")

Output :

b is greater than a

In this example we use two variables, a and b, which are used as part of the if statement to test whether b is greater than a. As a is 100, and b is 151, we know that 151 is greater than 100, and so we print to screen that "b is greater than

Note: Python relies on indentation (whitespace at the beginning of a line) to define scope in the code. Other programming languages often use curly-brackets for this purpose.
If statement, without indentation will raise an error.

Elif

The elif keyword is pythons way of saying "if the previous conditions were not true, then try this condition".

a = 151 b = 151 if b > a: print("b is greater than a") elif a == b: print("a and b are equal")

Output :

a and b are equal

In this example a is equal to b, so the first condition is not true, but the elif condition is true, so we print to screen that "a and b are equal".

Else

The else keyword catches anything which isn't caught by the preceding conditions.

a = 151 b = 100 if b > a: print("b is greater than a") elif a == b: print("a and b are equal") else: print("a is greater than b")

Output :

a is greater than b

In this example a is greater than b, so the first condition is not true, also the elif condition is not true, so we go to the else condition and print to screen that "a is greater than b".

More Coming Soon!