Le Monday 30 June 2008 20:55:36 Norman Khine, vous avez écrit :
> Hello,
>
> I would like to count list items but am not 100% sure how to do it.
>
> Here is what I have so far:
>
> for brain in brains:
> x = getattr(brain, horizontal)
> y = getattr(brain, vertical)
> if x and y and (x, y) in table:
> table[(x, y)] += 1
> table[(x, '')] += 1
> table[('', y)] += 1
> table[('', '')] += 1
>
> but when I run this, I get the following error on the line:
>
> if x and y and (x, y) in table:
>
> TypeError: list objects are unhashable
>
> where:
>
> x = ['airlines-scheduled', 'airport-car-parking']
>
lists are not hashable because hashing a mutable type would be dangerous, but
tuples are if all their items are hashable too. Just replace x by tuple(x).
--
Cédric Lucantis
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