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sorting a list of lists by an element
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sorting a list of lists by an element

I have a list of lists that I want to sort, something like :

data = [[0,False,'c'], [0,True,'z'], [1,False,'P'], [0,True,'A']]
I want all lists that have a True value at the top of Data, like :

sortingFuntion(data) = [[0,True,'z'], [0,True,'A'], [0,False,'c'], [1,False,'P']]
I can access the boolean with Data[i][1] in a for loop but I can't come up with how to transmit that value as a criteria to sorted()

Yoriz write Sep-10-2021, 03:16 PM:
Please post all code, output and errors (in their entirety) between their respective tags. Refer to BBCode help topic on how to post. Use the "Preview Post" button to make sure the code is presented as you expect before hitting the "Post Reply/Thread" button.
Use sorted with a custom key function
data = [[0, False, "c"], [0, True, "z"], [1, False, "P"], [0, True, "A"]]
sorted_data = sorted(data, key=lambda x: x[1], reverse=True)
[[0, True, 'z'], [0, True, 'A'], [0, False, 'c'], [1, False, 'P']]

Instead of using lamda you can also use itemgetter from the operator module
from operator import itemgetter

data = [[0, False, "c"], [0, True, "z"], [1, False, "P"], [0, True, "A"]]
sorted_data = sorted(data, key=itemgetter(1), reverse=True)
And for the folks that don't like lambdas, in this case itemgetter is possible as well.

from operator import itemgetter
sorted_data = sorted(data, key=itemgetter(1), reverse=True)
Thanks a lot !

I am fairly new to programming, will look up the lamda and itemgetter functions

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