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I would appreciate some help with a python piece of code im having issues with.

I have a list which contains strings. Here is a snippet of the list. It is a lot longer though.

[['AAPL', '1d', '58.82', '155.04'], ['MSFT', '1d', '63.16', '118.6']]

What i am trying to do is to sort the list at index 3 (so the values '155.04' , '118.6' etc). I have tried the following, which doesn't work since i have floats as string i presume. 

sorted(list, key=itemgetter(3), reverse=True)

I've looked into using sort() and sorted() but i cant seem to find a way to both sort ints as strings and also at a particular index.There are no error messages, its just not in the correct order.

Patrick Artner
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Damien Borowski
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2 Answers2

1

You can use a lambda to convert to float just for the comparison

values = [['AAPL', '1d', '58.82', '155.04'], ['MSFT', '1d', '63.16', '118.6']]
values = sorted(values, key=lambda x:float(x[3]), reverse=True)
# values stays the same the data is already reverse sorted by the 4th value
azro
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0

Your sort-key has to convert the last element of each sublist to a float.

>>> sorted(lst, key=lambda sublist: float(sublist[-1]), reverse=True)
[['AAPL', '1d', '58.82', '155.04'], ['MSFT', '1d', '63.16', '118.6']]

You could write that lambda function as a non-anonymous function for readability

def last_as_float(lst):
    return float(lst[-1])

and then pass key=last_as_float.

timgeb
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