Tuple as Key in Dict Help!

[Niner710]

Hi,

I have a dictionary with the key as a tuple.

 x = { ('AA',1,3):0.56, ('BB',0,3):0.70, ('AA',1,3):0.10, ('CC',1,3):0.60  }

I would like to get all the values where the key is equal to...

('AA',1,3)

However, when I use it only returns the last value where ('AA',1,3) is found.

 x.get( ('AA',1,3) )

How would I do this to get all the values where ('AA,1,3) is satisfied. Therefore, I would like something where I can return both 0.56 and 0.10.

[TrustyTony]

You must collect values as list or other collection type. Now you overwrite values and only last stays.

[jlm699]

You could create your own class based on dictionary that checks whether that key already exists in __setattr__ and then add the value to a list/tuple. When you do your get() you can then use isinstance to act accordingly.

[TrustyTony]

You can also use defaultdict(list) (form module collections) and append values there.

[Niner710]

Ok, I'm a little unsure how to implement this. Is their any example or link that you think would help clarify for this for me? Thanks.

[TrustyTony]

from collections import defaultdict
values = defaultdict(list)
for n in range(20):
    values[n % 2].append(n)
print values
"""Output:
defaultdict(<type 'list'>, {0: [0, 2, 4, 6, 8, 10, 12, 14, 16, 18], 1: [1, 3, 5, 7, 9, 11, 13, 15, 17, 19]})
"""

[Niner710]

Thanks PyTony. That is actually really helpful.

[Niner710]

Is there any way to slice the dictionary to look for values. Here is sample code that I created.

from collections import defaultdict

x = [ ('SET',1,2,1,1,0.23333),('SET',1,2,1,1,0.333),('SET',2,2,1,1,0.5),('SET',2,2,1,1,0.1), ('SET',1,2,1,1,0.333), ('RESET',2,2,1,1,0.272) ]
d = defaultdict(list)
for aa,bb,cc,dd,ee,ff in x:
    d[aa,bb,cc,dd,ee].append(ff)
d.get(('SET',1,2,1,1))

The number that I am interested in is the last number of my key tuple.
With my current d.get(('SET',1,2,1,1)) I would get a list [0.23333,0.3333]. Is there any way to slice this dictionary so that I could just specify

   d.get( ('SET') ) 

and return the other values in the key that correspond to all key tuples that have 'SET' instead of having to do d.get(('SET',1,2,1,1))

[TrustyTony]

Something like:

from collections import defaultdict

d = defaultdict(list)
for key, value in ( (('SET',1,2,1,1),0.23333),
                    (('SET',1,2,1,1),0.333),
                    (('SET',2,2,1,1),0.5),
                    (('SET',2,2,1,1),0.1),
                    (('SET',1,2,1,1),0.333),
                    (('RESET',2,2,1,1),0.272)
                    ):
    d[key].append(value)

print d
print [d[key] for key in d if key[0]=='SET']