Notice: This page requires JavaScript to function properly.
Please enable JavaScript in your browser settings or update your browser.Lära Dicts | Section 1
Python - Music

Svep för att visa menyn

book
Dicts

Dictionaries in Python allow you to store data in a structured way, associating unique keys with specific values. This is particularly useful in music analytics, where you often need to organize and access data efficiently.

In Python, a dictionary is a collection of key-value pairs. Think of it as a music library, where each track's title (key) is associated with its details like artist, duration, or genre (value). Dictionaries are defined using curly braces {} and key-value pairs are separated by colons :.

Example:

python

You can access the values in a dictionary by using the keys. For example, to get the artist of "Bohemian Rhapsody", you would use track_details["Bohemian Rhapsody"]["artist"]. Additionally, dictionaries allow you to add new key-value pairs or update existing ones. For instance, if you want to update the duration of "Imagine", you can simply assign a new value: track_details["Imagine"]["duration"] = 185.


              
12345678910

            
track_details = {
    "Bohemian Rhapsody": {"artist": "Queen", "duration": 354, "genre": "Rock"},
    "Imagine": {"artist": "John Lennon", "duration": 183, "genre": "Pop"}
}
bohemian_artist = track_details["Bohemian Rhapsody"]["artist"]
print(bohemian_artist)

track_details["Imagine"]["duration"] = 185
imagine_duration = track_details["Imagine"]["duration"]
print(imagine_duration)
copy

You can use loops to iterate over dictionaries, which is useful for processing all key-value pairs. For example, to print each track's details:


              
12345678

            
track_details = {
    "Stairway to Heaven": {"artist": "Led Zeppelin", "duration": 482, "genre": "Rock"},
    "Hey Jude": {"artist": "The Beatles", "duration": 431, "genre": "Pop"},
    "Hotel California": {"artist": "Eagles", "duration": 390, "genre": "Rock"}
}

for track, details in track_details.items():
    print(f"{track}: {details}")
copy
Uppgift

Swipe to start coding

Complete the filter_popular_tracks function that filters tracks by excluding those with popularity below a certain threshold and returns their IDs. This function is useful for organizing and displaying track information based on popularity criteria.

Inputs:

  • tracks: A list of dictionaries, each representing a track with keys such as track_id and track_popularity.
  • min_popularity: An integer representing the minimum popularity threshold.

Steps:

  • Filter Tracks: Iterate over the tracks list and check if the track's popularity is greater than or equal to min_popularity. If so, add the track's ID to the result list.

Lösning

Switch to desktopByt till skrivbordet för praktisk övningFortsätt där du är med ett av alternativen nedan
Var allt tydligt?

Hur kan vi förbättra det?

Tack för dina kommentarer!

Avsnitt 1. Kapitel 5
py

solution.py

py

main.py

Vi beklagar att något gick fel. Vad hände?

Fråga AI

expand
ChatGPT

Fråga vad du vill eller prova någon av de föreslagna frågorna för att starta vårt samtal

book
Dicts

Dictionaries in Python allow you to store data in a structured way, associating unique keys with specific values. This is particularly useful in music analytics, where you often need to organize and access data efficiently.

In Python, a dictionary is a collection of key-value pairs. Think of it as a music library, where each track's title (key) is associated with its details like artist, duration, or genre (value). Dictionaries are defined using curly braces {} and key-value pairs are separated by colons :.

Example:

python

You can access the values in a dictionary by using the keys. For example, to get the artist of "Bohemian Rhapsody", you would use track_details["Bohemian Rhapsody"]["artist"]. Additionally, dictionaries allow you to add new key-value pairs or update existing ones. For instance, if you want to update the duration of "Imagine", you can simply assign a new value: track_details["Imagine"]["duration"] = 185.


              
12345678910

            
track_details = {
    "Bohemian Rhapsody": {"artist": "Queen", "duration": 354, "genre": "Rock"},
    "Imagine": {"artist": "John Lennon", "duration": 183, "genre": "Pop"}
}
bohemian_artist = track_details["Bohemian Rhapsody"]["artist"]
print(bohemian_artist)

track_details["Imagine"]["duration"] = 185
imagine_duration = track_details["Imagine"]["duration"]
print(imagine_duration)
copy

You can use loops to iterate over dictionaries, which is useful for processing all key-value pairs. For example, to print each track's details:


              
12345678

            
track_details = {
    "Stairway to Heaven": {"artist": "Led Zeppelin", "duration": 482, "genre": "Rock"},
    "Hey Jude": {"artist": "The Beatles", "duration": 431, "genre": "Pop"},
    "Hotel California": {"artist": "Eagles", "duration": 390, "genre": "Rock"}
}

for track, details in track_details.items():
    print(f"{track}: {details}")
copy
Uppgift

Swipe to start coding

Complete the filter_popular_tracks function that filters tracks by excluding those with popularity below a certain threshold and returns their IDs. This function is useful for organizing and displaying track information based on popularity criteria.

Inputs:

  • tracks: A list of dictionaries, each representing a track with keys such as track_id and track_popularity.
  • min_popularity: An integer representing the minimum popularity threshold.

Steps:

  • Filter Tracks: Iterate over the tracks list and check if the track's popularity is greater than or equal to min_popularity. If so, add the track's ID to the result list.

Lösning

Switch to desktopByt till skrivbordet för praktisk övningFortsätt där du är med ett av alternativen nedan
Var allt tydligt?

Hur kan vi förbättra det?

Tack för dina kommentarer!

Avsnitt 1. Kapitel 5
Switch to desktopByt till skrivbordet för praktisk övningFortsätt där du är med ett av alternativen nedan
Vi beklagar att något gick fel. Vad hände?
some-alt