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Python Introducing Lists Build an Application Multidimensional Musical Groups

Luis Martinez
Luis Martinez
5,986 Points
Posted by Luis Martinez
Luis Martinez
5,986 Points

why is my code printing everything if Im excluding groups with more than 3 objects in them??

i even made a copy of the multi-dimentional list and so far nothing seems to work. What am I missing?

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"],
]

s = ", "
# Your code here
for groups in musical_groups:
    print(s.join(groups))
    groups = groups.copy()
    if len(groups) == 2:
        print(groups)

3 Answers

akoniti
akoniti
1,410 Points
akoniti
akoniti
1,410 Points

Hi Luis,

The first thing I see is that your for loop is actually printing the groups before checking the length with this early line:

print(s.join(groups))

Second, your length check isn't actually finding any results, because all of these lists contain 3 or more values.

So, if you modified your code as follows, it will just print groups with 3 or less values:

for groups in musical_groups:
    #print(s.join(groups))
    #groups = groups.copy()
    if len(groups) < 4:
        #print(groups)
        print(s.join(groups))

I left your original lines in, commented out, so you could more easily follow the changes I made. Good luck!

Luis Martinez
Luis Martinez
5,986 Points
Luis Martinez
Luis Martinez
5,986 Points

oh that's so true! I didn't even realize it!

KRIS NIKOLAISEN
KRIS NIKOLAISEN
54,972 Points
KRIS NIKOLAISEN
KRIS NIKOLAISEN
54,972 Points

I'm kind of confused as to what you are asking. Everything prints from this line:

print(s.join(groups))

then you have a condition checking for a length of 2. Since none of the groups match this nothing further prints. If you change the 2 to 3 you will print all the groups with three members in addition to the above.

Luis Martinez
Luis Martinez
5,986 Points
Luis Martinez
Luis Martinez
5,986 Points

thanks to both of you for your time! You guys are awesome!