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Python Introducing Lists Build an Application Multidimensional Musical Groups

Posted by Arturs Certuks
Arturs Certuks
13,059 Points

I don't follow which are the groups and which are the members and what exactly is asked for me to do here.

Seriously don't follow which of these are groups and which are members as some of these look like they could be a name of a band and some are clearly name and a surname of a person.. and they're all just mixed together there.

Therefore probably the task itself is easy, but I'm completely lost as I don't follow these.

groups.py 
musical_groups = [
    ["Ad Rock", "MCA", "Mike D."],
    ["John Lennon", "Paul McCartney", "Ringo Starr", "George Harrison"],
    ["Salt", "Peppa", "Spinderella"],
    ["Rivers Cuomo", "Patrick Wilson", "Brian Bell", "Scott Shriner"],
    ["Chuck D.", "Flavor Flav", "Professor Griff", "Khari Winn", "DJ Lord"],
    ["Axl Rose", "Slash", "Duff McKagan", "Steven Adler"],
    ["Run", "DMC", "Jam Master Jay"],
]
# Your code here

1 Answer

Jesus Reyes
Jesus Reyes
1,946 Points
Jesus Reyes
Jesus Reyes
1,946 Points

Hello Arturs, this exercise is to manage list of 2 dimensions, which is a fancy way to call a list that store lists in its items. If you try to read this list you get two sets of information:

 musical_groups = [
    item1,
    item2,
    item3,
    item.....
]

this represents a normal list that could also be written as

 musical_groups = [item1, item2, item3, item.....]

the catch in this example is that each item is also a list, with its own items inside so to make it more "readable" the main list or the first "dimension" of the list is written vertically (each item in a line) and the other "dimension", which are the items inside the main list's items, are written horizontally as a usual list.

So going back to the exercise, if you read the horizontal lists (second dimention) it seems you are reading names (even do some of them are quite weird XD) and they are "grouped" as items of the first "dimension" or "main list" which implies these are music groups. so if we go back to the code it can be read as follows:

 musical_groups = [
    music_group1,
    music_group2,
    music_group3,
    music_group....
]

and each music group has a group of members so

 musical_groups = [
    [member1, member2, member...],
    [member1, member2, member...],
    [member1, member2, member...],
    [member1, member2, member...],
]

i hope this helps