basic.md

Data Types

Numeric

Interger

Complex Number

Float

Dictionary

Boolean

Set

Sequence Type

Strings

List

tuple

Numeric

Numeric value can be interger, floating number or even complex numbers. These values are defined as int, float and complex class in Python.

Python program to demonstrate numeric value

c = 1 + 1j print("Type of a, b, and c is " , type(2), type(1.5), type(c) , "respectively")

output: Type of a, b, and c is <class 'int'> <class 'float'> <class 'complex'> respectively

Sequence

In Python, a sequence is the ordered collection of similar or different data types.

String

List

Tuple

1. String: A string is a collection of one or more characters put in a single quote, double-quote or triple quote. In python there is no character data type, a character is a string of length one. It is represented by str class. Strings in Python can be created using single quotes or double quotes or even triple quotes.

Python Program for Creation of String

String with single, double and triple quotes

print('Welcome to the Python World', " I am a Pythonista", '''and I lives in world of "Python"''')

output: Welcome to the Python World I am a Pythonista and I lives in world of "Python"

Python Program to Access characters of String

String1 = "Pythonista"

Print First character

print(String1[0])

Print Last character

print(String1[-1])

Deleting/Updating from a String –

In Python, Updation or deletion of characters from a String is not allowed because Strings are immutable. Only new strings can be reassigned to the same name.

Python Program to Update / delete character of a String

String1 = "Hello, I'm a Pythonista"

Updating a character

String1[2] = 'a'

Output: TypeError: ‘str’ object does not support item assignment

Deleting a character

del String1[2]

Output: TypeError: ‘str’ object doesn’t support item deletion

String Slicing in Python

Python slicing is about obtaining a sub-string from the given string by slicing it respectively from start to end. Python slicing can be done in two ways.

slice() Constructor

Extending Indexing

String slicing

String ='Pythonista'

Using indexing sequence

print(String[:3]) print(String[1:5:2]) print(String[-1:-12:-2])

Prints string in reverse

print("\nReverse String") print(String[::-1])

Output: Pyt yh asnhy Reverse String atsinohtyP

Curious? okay please refer holybook of coding to know more https://www.geeksforgeeks.org/string-slicing-in-python/

List

Lists are just like the arrays, declared in other languages. A single list may contain DataTypes like Integers, Strings, as well as Objects. The elements in a list are indexed according to a definite sequence and the indexing of a list is done with 0 being the first index. It is represented by list class.

Creating a List

List = []
print(List)

Creating a list of strings

List = ['Pythonista', 'Pythoneer'] print(List)

Creating a Multi-Dimensional List

List = [['Python', 'For'], ['Beginners']]
print(List)

Adding Elements to a List: Using append(), insert() and extend()

Addition of elements in a List

Creating a List

List = []

Using append()

List.append(1)
List.append(2) print(List)

Using insert()

List.insert(3, 12)
List.insert(0, 'Geeks') print(List)

Using extend()

List.extend([8, 'Geeks', 'Always'])
print(List)

accessing of element from list

List = [1, 2, 3, 4, 5, 6]

accessing a element

print(List[0])
print(List[2])

Negative indexing

print the last element of list

print(List[-1])

print the third last element of list

print(List[-3])