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Dictionary and Sets in PYTHON

What do you mean Dictionary ??



A dictionary is a collection of key-value pairs.

Its theory is not so important we are directly going on its syntax i.e. the way to write it in python language.
Let we have a dictionary named mydict, so we can write it as :-

mydict  =  { "Fast": "In a quick manner", "Hello": "Hey", "See": "Watch" }

This above line is the syntax, how we write a dictionary in the terminal. If you notice, in the above dictionary we have some words in the left and their meanings in the right.

Fast - In a quick manner

Hello - Hey

See - Watch


We can add more words and their meanings according to our choice.

Now let us see an example :-



We can also use int, str, float, bool, list, tuple in place of values.
Lets see an example :-



Now an important thing, it could be a bit confusing but still you should dtry to understand it. We can make an another dictionary inside a dictionary means a dictionary inside a dictionary. If you don't understand then lets see another example :-




Properties of Python Dictionary :-

1.)  It is unordered.
2.)  It can be changed or updated.
3.)  It can't contain duplicate keys.
4.)  It is indexed

Some Python Dictionary Methods :-











Now, what is a Set ?

Sets are the collection of well-defined objects and elements.

A set is written as S  =  {1, 2, 3, 4, 5, 2, 4}. But if we going to print this set, then we will see that in the command there  2 and 4 are twice but in the result statement there 2 and 4 are only once. This is because sets have the property that they do not print repetitive values. Hence if something is twice or thrice or even higher then it is printed only once. 
Lets see in the terminal :-




Some Properties of Sets :-

1.) Sets are ordered.
2.) Sets are unindexed.
3.) There id no way to change items in set.
4.) Sets can't contain repetitive values.


Some methods of Sets :-

1.)  To add other element in a set "myset", so use the following command myset.add(element)
2.)  To remove any element from a set named "myset", use command myset.remove(element)
3.)  To find the length of the set use command print(len(myset))
4.)  You can also use POP method which will remove any random element form the set and the command to use it is myset.pop()





So thats it in the Dictionary and Sets. I am not giving proper codes for set methods because it is easy to implement and I had also given the commands you just remember them and practice.

Hope you like the tutorial, if so then please share it with your friends and help them to learn python.




John Veer
Contact mail id  -  john.veer.utube@gmail.com
Thanks for reading !


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