Convert a dictionary into a list of tuples

Question

Given a dictionary like this:

dic = {(7, 3): 18.51, (1, 3): 18.751, (5, 6): 34.917, (9, 8): 18.9738}

I want to convert it to a list of tuples like this:

my_list = [(7, 3, 18.51), (1, 3, 18.751), (5, 6, 34.917), (9, 8, 18.9738)]

I could have used a loop but I wonder if there is a neat way to do so instead of loops.

What have you tried and what is the problem with it? `.items()` alone gets you most of the way there. — jonrsharpe, Jan 22 '17 at 18:41

Willem Van Onsem · Answer 1 · 2017-01-22T18:45:42.987

5

Simply use list(..) on some generator:

my_list = list(key+(val,) for key,val in dic.items())

This works since:

list(..) takes as input an iterable and converts it to a list; and
key+(val,) for key,val dic.items() is a generator that takes a pair of key-values of dic and transforms it into a tuple appending the val to the key.

Since we use a generator for a list, we can simplify this with list comprehension:

my_list = [key+(val,) for key,val in dic.items()]

Finally mind that the order in which the tuples occur is not fixed this is because the order how a dict stores elements is not fixed as well.

edited Jan 22 '17 at 18:45

answered Jan 22 '17 at 18:41

Willem Van Onsem

No, that won't quite meet the OP's requirements. They have two-tuple keys and want a three-tuple output `(k1, k2, v)` – jonrsharpe Jan 22 '17 at 18:42
1

@jonrsharpe: I see, perhaps a more generic way is to use `+` since it could be possible that the key contains more items. – Willem Van Onsem Jan 22 '17 at 18:43
1

@Don.C: see updated answer. With thanks to jonrsharpe for the comment. – Willem Van Onsem Jan 22 '17 at 18:44

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