2. List & dictionary

List

 

The order of values is important.

Using the 'list' function allows you to utilize the order of values and the listed words or numbers to access the values.

 

a_list = [1,5,6,3,2]
a_list.append(99)
a_list.append(992)
a_list.append(919)
a_list.append(399)
print(a_list)

 

 

Result

 

 

 

a_list = [1,5,6,3,2]
result = a_list[:3]
print(result)

 

 

result

 

 

 

Dictionary

 

It stores values as key-value pairs.

 

a_dict = {'name' : 'bob', 'age' : 27}
result = a_dict['age']
print (result)

 

Result : 27

 

 

Dictional & List

a_dict = {'name' : 'bob', 'age' : 27, 'Friend' : ['Jay', 'Lisa']}
result = a_dict['Friend'][1]
print (result)

 

Result : Lisa

 

 

Practice 

Get the reult of Science score from smith

 

people = [
    {'name': 'bob', 'age': 20, 'score':{'math':90,'science':70}},
    {'name': 'carry', 'age': 38, 'score':{'math':40,'science':72}},
    {'name': 'smith', 'age': 28, 'score':{'math':80,'science':90}},
    {'name': 'john', 'age': 34, 'score':{'math':75,'science':100}}
]
result = people[2]['score']['science']
print(result)

 

result : 90

 

I studied about the List and Dictionary functions. With lists, values are retrieved based on the order of the columns, whreas with dictionaries, values are retrieved based on string values. Both can be used, and they seem to be the most basic but important concepts.