GTXY20 wrote:
> Hello,
>
> Any way to display the count of the values in a dictionary where the
> values are stored as a list? here is my dictionary:
>
> {'1': ['a', 'b', 'c'], '3': ['a', 'b', 'c'], '2': ['a', 'b', 'c'], '4':
> ['a', 'c']}
>
> I would like to display count as follows and I would not know all the
> value types in the values list:
>
> Value QTY
> a 4
> b 3
> c 4
You need two nested loops - one to loop over the dictionary values and
one to loop over the individual lists. collections.defaultdict is handy
for accumulating the counts but you could use a regular dict also:
In [4]: d={'1': ['a', 'b', 'c'], '3': ['a', 'b', 'c'], '2': ['a', 'b',
'c'], '4': ['a', 'c']}
In [5]: from collections import defaultdict
In [6]: counts=defaultdict(int)
In [7]: for lst in d.values():
...: for item in lst:
...: counts[item] += 1
...:
In [8]: counts
Out[8]: defaultdict(<type 'int'>, {'a': 4, 'c': 4, 'b': 3})
In [10]: for k, v in sorted(counts.items()):
....: print k,v
....:
....:
a 4
b 3
c 4
> Also is there anyway to display the count of the values list
> combinations so here again is my dictionary:
>
> {'1': ['a', 'b', 'c'], '3': ['a', 'b', 'c'], '2': ['a', 'b', 'c'], '4':
> ['a', 'c']}
>
>
> And I would like to display as follows
>
> QTY Value List Combination
> 3 a,b,c
> 1 a,c
Again you can use a defaultdict to accumulate counts. You can't use a
mutable object (such as a list) as a dict key so you have to convert it
to a tuple:
In [11]: c2=defaultdict(int)
In [13]: for v in d.values():
....: c2[tuple(v)] += 1
....:
In [14]: c2
Out[14]: defaultdict(<type 'int'>, {('a', 'b', 'c'): 3, ('a', 'c'): 1})
Printing in order of count requires switching the order of the (key,
value) pairs:
In [15]: for count, items in sorted( ((v, k) for k, v in c2.items()),
reverse=True):
....: print count, ', '.join(items)
....:
3 a, b, c
1 a, c
or using a sort key:
In [16]: from operator import itemgetter
In [17]: for items, count in sorted(c2.items(), key=itemgetter(1),
reverse=True):
....: print count, ', '.join(items)
....:
3 a, b, c
1 a, c
Kent
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