[Tutor] how to delete some quasi-duplicated keys

[lina]

On Fri, Nov 25, 2011 at 5:06 PM, Steven D'Aprano <steve at pearwood.info> wrote:
> lina wrote:
>>>>>
>>>>> pairs
>>
>> {('66', '69'): 217, ('69', '66'): 75, ('64', '71'): 25}
>>
>>
>> such as here ('66', '69') and ('69', '66') is one key,
>>
>> I wanna keep only one and add the value of those two keys, above is a
>> very simple example:
>
>
> Which one do you want to keep?
>
It does not matter, the order is not important,

> If the order ('66', '69') is unimportant, you should use a frozenset instead
> of a tuple. In your code, where you set the pairs in the first place,
> instead of doing:

>
> pair = ('66', '69')  # however you build the pair
> pairs[pair] = value
>
> (or how ever you set the initial values), change it to this:
>
> pair = frozenset(('66', '69'))
> pairs[pair] = pairs.get(pair, 0) + value

I don't get this "pairs.get" part.
 pairs[pair]=pairs.get(pair,0)+parts[2]
TypeError: unsupported operand type(s) for +: 'int' and 'str'


or line in f.readlines():
            parts=line.split()
            #pair=set((parts[0],parts[1]))
            if (parts[0],parts[1]) not in dehydrons.keys():
                dehydrons[(parts[0],parts[1])]=parts[2]
                occurence[(parts[0],parts[1])]=1
                pair=frozenset(('parts[0]','parts[1]'))
                pairs[pair]=pairs.get(pair,0)+parts[2]
            else:
                occurence[(parts[0],parts[1])]+=1

I upload the file in:


https://docs.google.com/open?id=0B93SVRfpVVg3NTg5YTkwMGUtMzdiNi00ZGI2LWE5ZGYtMTFmMTc0OTZhMzZl
https://docs.google.com/open?id=0B93SVRfpVVg3NGQwZDRhNDMtMDUzZi00NDIxLWE2MDAtZGM0ZWEzZDczYTMz

>
>
>
>
> --
> Steven
>
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