Python Part6 Sets and Dictionaries

17 12 2021
List
Tuple
Set
Dictionary

List - [ ]
-ordered(indexed),changeable,Allow duplicates
tuple - ( )
-ordered(idexed),unchangeable,Allow duplicates
set - { }
-unordered(unindexed),unchangeable,not allow duplicates
(but you can remove items and add new items.)

Sets are written with curly brackets.

set1={"banna", "apple","oranges"}

setA={25,110,143,21,68,22,80,53}
SetB={22,23,80,20,53,443,67}
setA
{68, 110, 143, 80, 21, 22, 53, 25}
SetB
{80, 67, 20, 53, 22, 23, 443}
setA[0]

setA[3:]

setA
{68, 110, 143, 80, 21, 22, 53, 25}
setA.add(3389)
setA
{68, 110, 143, 80, 21, 22, 53, 25, 3389}
setA.union(SetB)
{67, 68, 110, 143, 80, 20, 21, 22, 53, 23, 25, 443, 3389}
setA.difference(SetB)
{68, 110, 143, 21, 25, 3389}
SetB
{80, 67, 20, 53, 22, 23, 443}
SetB.difference(setA)
{67, 20, 443, 23}
setA.intersection(SetB)
{80, 53, 22}
SetB.intersection(setA)
{80, 53, 22}
setC={110,143,25}
setC
{25, 110, 143}
setA
{68, 110, 143, 80, 21, 22, 53, 25, 3389}
setA.issuperset(setC)
True
setC.issubset(setA)
True
setA.symmetric_difference(SetB)
{67, 68, 143, 20, 21, 23, 25, 110, 443, 3389}

Dictionary

Dictionaries are used to store data values in key:value pairs.

A dictionary is a collection which is ordered*, changeable and do not allow duplicates.

As of Python version 3.7, dictionaries are ordered. In Python 3.6 and earlier, dictionaries are unordered.

Dictionaries are written with curly brackets, and have keys and values:

dict1={ "Name":"Navya","Age":"21","Area":"Hyderabad"}


dict1
{'Name': 'Navya', 'Age': '21', 'Area': 'Hyderabad'}

dict1[0]


dict1["Name"]
'Navya'

dict1["Age"]
'21'

dict1["Area"]="Pune"
dict1
{'Name': 'Navya', 'Age': '21', 'Area': 'Pune'}

dict1.values()
dict_values(['Navya', '21', 'Pune'])

dict1.keys()
dict_keys(['Name', 'Age', 'Area'])