Course Content
Learn Python from Scratch
Learn Python from Scratch
Dictionaries (1/2)
In previous tasks, we store characteristics and names they belong to a bit equivalent. I think you agree that it would be great if we could reach information for something by its name, not finding indexes. This problem can be solved by using dictionaries - one more data type in Python.
Dictionary can be represented as key:value. It's important that keys in the dictionary can't repeat, while values can. To create dictionary use {key1: value1, key2: value2, ...}
or dict(key1: value1, key2: value2, ...)
. Keys must be immutable (number, string, tuple).
For example, let's create dictionary with our first three countries.
Country | Area | Population |
USA | 9629091 | 331002651 |
Canada | 9984670 | 37742154 |
Germany | 357114 | 83783942 |
# create dictionary countries_dict = {'USA': (9629091, 331002651), 'Canada': (9984670, 37742154), 'Germany': (357114, 83783942)} print(countries_dict)
Please note, that I placed countries' characteristics inside the tuple, as we mentioned before it greatly fits when we have some object characteristics.
Now if I want to get, for example, information for Canada, I can simply use d[key]
function.
countries_dict = {'USA': (9629091, 331002651), 'Canada': (9984670, 37742154), 'Germany': (357114, 83783942)} # information about Canada print(countries_dict["Canada"])
Task
Create a dictionary with keys - names of people and values - their respective age and height (as a tuple). Print information for Alex.
Name | Age | Height |
Alex | 23 | 178 |
Noah | 34 | 189 |
Peter | 29 | 175 |
Thanks for your feedback!
Dictionaries (1/2)
In previous tasks, we store characteristics and names they belong to a bit equivalent. I think you agree that it would be great if we could reach information for something by its name, not finding indexes. This problem can be solved by using dictionaries - one more data type in Python.
Dictionary can be represented as key:value. It's important that keys in the dictionary can't repeat, while values can. To create dictionary use {key1: value1, key2: value2, ...}
or dict(key1: value1, key2: value2, ...)
. Keys must be immutable (number, string, tuple).
For example, let's create dictionary with our first three countries.
Country | Area | Population |
USA | 9629091 | 331002651 |
Canada | 9984670 | 37742154 |
Germany | 357114 | 83783942 |
# create dictionary countries_dict = {'USA': (9629091, 331002651), 'Canada': (9984670, 37742154), 'Germany': (357114, 83783942)} print(countries_dict)
Please note, that I placed countries' characteristics inside the tuple, as we mentioned before it greatly fits when we have some object characteristics.
Now if I want to get, for example, information for Canada, I can simply use d[key]
function.
countries_dict = {'USA': (9629091, 331002651), 'Canada': (9984670, 37742154), 'Germany': (357114, 83783942)} # information about Canada print(countries_dict["Canada"])
Task
Create a dictionary with keys - names of people and values - their respective age and height (as a tuple). Print information for Alex.
Name | Age | Height |
Alex | 23 | 178 |
Noah | 34 | 189 |
Peter | 29 | 175 |
Thanks for your feedback!
Dictionaries (1/2)
In previous tasks, we store characteristics and names they belong to a bit equivalent. I think you agree that it would be great if we could reach information for something by its name, not finding indexes. This problem can be solved by using dictionaries - one more data type in Python.
Dictionary can be represented as key:value. It's important that keys in the dictionary can't repeat, while values can. To create dictionary use {key1: value1, key2: value2, ...}
or dict(key1: value1, key2: value2, ...)
. Keys must be immutable (number, string, tuple).
For example, let's create dictionary with our first three countries.
Country | Area | Population |
USA | 9629091 | 331002651 |
Canada | 9984670 | 37742154 |
Germany | 357114 | 83783942 |
# create dictionary countries_dict = {'USA': (9629091, 331002651), 'Canada': (9984670, 37742154), 'Germany': (357114, 83783942)} print(countries_dict)
Please note, that I placed countries' characteristics inside the tuple, as we mentioned before it greatly fits when we have some object characteristics.
Now if I want to get, for example, information for Canada, I can simply use d[key]
function.
countries_dict = {'USA': (9629091, 331002651), 'Canada': (9984670, 37742154), 'Germany': (357114, 83783942)} # information about Canada print(countries_dict["Canada"])
Task
Create a dictionary with keys - names of people and values - their respective age and height (as a tuple). Print information for Alex.
Name | Age | Height |
Alex | 23 | 178 |
Noah | 34 | 189 |
Peter | 29 | 175 |
Thanks for your feedback!
In previous tasks, we store characteristics and names they belong to a bit equivalent. I think you agree that it would be great if we could reach information for something by its name, not finding indexes. This problem can be solved by using dictionaries - one more data type in Python.
Dictionary can be represented as key:value. It's important that keys in the dictionary can't repeat, while values can. To create dictionary use {key1: value1, key2: value2, ...}
or dict(key1: value1, key2: value2, ...)
. Keys must be immutable (number, string, tuple).
For example, let's create dictionary with our first three countries.
Country | Area | Population |
USA | 9629091 | 331002651 |
Canada | 9984670 | 37742154 |
Germany | 357114 | 83783942 |
# create dictionary countries_dict = {'USA': (9629091, 331002651), 'Canada': (9984670, 37742154), 'Germany': (357114, 83783942)} print(countries_dict)
Please note, that I placed countries' characteristics inside the tuple, as we mentioned before it greatly fits when we have some object characteristics.
Now if I want to get, for example, information for Canada, I can simply use d[key]
function.
countries_dict = {'USA': (9629091, 331002651), 'Canada': (9984670, 37742154), 'Germany': (357114, 83783942)} # information about Canada print(countries_dict["Canada"])
Task
Create a dictionary with keys - names of people and values - their respective age and height (as a tuple). Print information for Alex.
Name | Age | Height |
Alex | 23 | 178 |
Noah | 34 | 189 |
Peter | 29 | 175 |