LISTS:

Python is a mostly used popular language to develop webpage or software. This article helps how to

Create

Access elements

Remove elements

List is

Ordered : order of element insertion are maintained

Heterogeneous : contain data of different datatypes

Changeable/Mutable : elements can be modified

Duplicate : List allows to store duplicate values

Create

Using list() constructor : values inside the list() separated by coma (,)

l1=list((11,12,13,14,15))
print(l1) #It will print [11,12,13,14,15]

Using ( [] ) : enclosing the items inside the [ ]

Access

Using slicing operator [ m:n ]

Add

l1 = [11,12,13,14,15]

append(n)	add at the end l1.append(16) #It will print [11,12,13,14,15,16]
insert(p,n)	add at the specific position #insert 33 at position 3 l1.insert(3,33) #It will print [11,12,13,33,,14,15]
extend(l1)	add another list at the end of the list l1.extend([10,9,8]) #It will print [11,12,13,14,15,10,9,8]

Remove

l1 = [11,12,13,14]

remove(value)	Remove first occurrence of element(n) l1.remove(12) #It will print [11,13,14]
pop(index)	1. Removes and returns the value of passing index 2. Remove last elements if index is not passed l1.pop(2) #It will print [11,12,14] l1.pop() #It will print [11,12]
clear()	Remove all elements Output empty list l1.clear() #It will print []
del listname	Delete the entire list del l1 #delete entire list

DICTIONARY:

In python dictionary is a built-in data types.

It defines one-to-one relationship between keys and values.

Dictionary contains keys : value pair.

Dictionary are indexed by keys.

Dictionary defined with curly braces { }.

Dictionary Items

Ordered : ordered of item insertion are maintained

Changeable/Mutable : items can modified

Not Duplicate : dictionary cannot have two items with the same key

Create

sd={ "Country":"India", "Capital":"Delhi", "PM":"Modi" }
print(sd)
OUTPUT:
{'Country': 'India' , 'Capital': 'Delhi', 'PM': 'Modi'}

Print the value of the dictionary

sd={ "Country": "India", "Capital": "Delhi", "PM": "Modi" }
print sd[Country]
print sd[Capital]
print sd[PM]
OUTPUT:
India
Delhi
Modi

Duplicate value will overwrite

sd={ "Country": "India", "Country": "Japan" "Capital": "Delhi", "PM": "Modi" }
print(sd)
OUTPUT:
{'Country': 'Japan' , 'Capital': 'Delhi', 'PM': 'Modi}

Dictionary Length

print(len(sd))
OUTPUT:
3

Data Types

sd={ "Country": "India", "Capital": "Delhi", "PM": "Modi", "Pollution": "True", "States": ["West Bengal", "Bihar", "Punjab"........] }
print(sd)
OUTPUT:
{'Country': 'India', 'Capital': 'Delhi', 'PM': 'Modi', 'Pollution': 'True', 'States': ['West Bengal', 'Bihar', 'Punjab'......]}

Type()

print(type(dict))
OUTPUT:
class 'dict'

Dict() Constructor

sd=dict(Country= "India", Capital= "Delhi", PM="Modi")
print(sd)
OUTPUT:
{'Country': 'India' , 'Capital': 'Delhi', 'PM': 'Modi'}

With lists and dictionaries, you can do more with less code in Python.