Dictionaries in Python in 5 mins

What is a Dictionary or Dict?

A dictionary is a data type used to store key-value pairs as we have in our English dictionary. It is useful when we want to save the data related to an entity at the same place. It is like saving an excel row in python in a column_header:column_value format

E.g

If we want to store the details(name, class, marks, address) of a student we can create different variables for this, or we can create only one variable of type dict and save the values in it.

Syntax:

s1={

‘Name’:’Tarun’,

‘Class’: 12,

‘Address’:’house number 11 xyz street ‘,

        ‘marks’:[90,89,67,84]

      }

As in the above code, we can see that a dictionary can save multiple data types. Variable “Name” is of type string, “Class” is of type int, “Address” is of type string, “Marks” is of type list. 

A dict can also store a dictionary in it and is called Nested Dictionary.

Syntax:

<variable name>=dict({key:value,key:value})

<variable name>={key:value,key:value}

A variable inside the dict can be accessed using its name

E.g

#to get the from the dictionary s1 created above

s1[‘Name’]

#to get the marks from dict s1

s1[‘Marks’]

Adding a key to the dict

# to add a new variable in the dict
s1[‘new_variable_name’]=new_variable_value

Removing a key from the dict

# to remove a variable from the dictionary

del(s1[‘variable name to be removed’])

Some Functions in Dictionary

clear():

Remove all items from the dictionary

keys():

Return a new view of the dictionary's keys

values():

Return a new view of the dictionary's values

copy():

Returns a copy of the dictionary

items():

Returns a list containing a tuple for each key-value pair

Conclusion

I hope you got an understanding of Dictionaries in python. Feel free to ask any doubt if you have.

Also, have a look at other related posts:

Variables and Data Types in Python

Hello World Program in Python

Why should you learn python in 2020