Unpack an array filled with lists

Question

I started with something like this:

[a,b,s,d]
[k,e,f,s,d]
[o,w,g]

Then I wanted to rearrange them by length in descending order so that I get this:

[k,e,f,s,d]
[a,b,s,d]
[o,w,g]

However, to do that, I appended each of those into an array as such:

arr = [[a,b,s,d], [k,e,f,s,d], [o,w,g]]

so that I could just use:

sorted(arr, key=len).reverse()

But now I can't unpack arr to just get:

[k,e,f,s,d]
[a,b,s,d]
[o,w,g]

Ideas?

Thanks.

@Ffisegydd They were originally in a txt file then I put each in an array — Student J, Jul 12 '14 at 14:43
Your lists were originally in a txt file? (They're lists, not arrays, arrays are completely different things in Python so please don't confuse them). And you want them back in a text file but in the correct order? — Ffisegydd, Jul 12 '14 at 14:45
No. Don't want them back in the text file. Just want them to be back in list form, so not inside that arr. I want to look at leach line's character individually. @Ffisegydd — Student J, Jul 12 '14 at 14:46
@PadraicCunningham I'm not asking how to reverse. I'm asking how to unpack — Student J, Jul 12 '14 at 14:48

score 0 · Answer 1 · answered Jul 12 '14 at 14:46

reverse() is an in-place function:

arr = [['a','b','s','d'], ['k','e','f','s','d'], ['o','w','g']] 
a = sorted(arr, key=len)
print a
# [['o', 'w', 'g'], ['a', 'b', 's', 'd'], ['k', 'e', 'f', 's', 'd']]
print a.reverse()
# None
print a
# [['k', 'e', 'f', 's', 'd'], ['a', 'b', 's', 'd'], ['o', 'w', 'g']]

reverse() has no output, but it does reverse the array.

Unpack an array filled with lists

1 Answers1