Python list of tuples with key values to dict

Question

I am having a hard time trying to convert a list of tuples, with key, values to a dictionary.

I have a list of tuples:

[('season', '1', 'episode', '1', 'showkey', '1736'),
('season', '1', 'episode', '2', 'showkey', '1737'),
('season', '1', 'episode', '3', 'showkey', '1738'),
('season', '1', 'episode', '4', 'showkey', '1739'),
('season', '1', 'episode', '5', 'showkey', '1740'),
('season', '1', 'episode', '6', 'showkey', '1741'),
('season', '1', 'episode', '7', 'showkey', '1742'),
('season', '1', 'episode', '8', 'showkey', '1743'),
('season', '1', 'episode', '9', 'showkey', '1744'),
('season', '1', 'episode', '10', 'showkey', '1745'),
('season', '1', 'episode', '11', 'showkey', '1746'),
('season', '1', 'episode', '12', 'showkey', '1747'),
('season', '1', 'episode', '13', 'showkey', '1748')]

how can I make a dictionary with the key value pairs like:

{'season':1, 'episode':2, 'showkey':1736}

Thanks for any help!

The output can be an array of dictionaries, but it can not be a single dictionary. — Paul, Aug 12 '15 at 04:51
That format for each type that you have there is really strange. How did you get your data into that format? — Danver Braganza, Aug 12 '15 at 04:51

Burhan Khalid · Accepted Answer · 2015-08-12T06:11:49.467

If you want one dictionary for each tuple:

>>> i = ('season', '1', 'episode', '2', 'showkey', '1737')
>>> dict(zip(i[::2], i[1::2]))
{'season': '1', 'episode': '2', 'showkey': '1737'}

To expand this for your list:

new_list = [dict(zip(i[::2], i[1::2])) for i in list_of_data]

This works by combining the following facts:

The dict() constructor takes an iterable of pairs which it can convert to key/value.
zip() will return tuples pairs from the two iterables passed to it.
Slicing allows you add a starting offset, and a step argument.

Combining the above:

First, we slice the tuple by odd positions i[::2] then by even positions, by skipping the first element i[1::2], this gives us two lists one representing the keys, the second the values:
```
>>> i[::2]
('season', 'episode', 'showkey')
>>> i[1::2]
('1', '2', '1737')
```

Next, we feed these two lists to zip to give us (key,value) pairs:

>>> zip(i[::2], i[1::2])
[('season', '1'), ('episode', '2'), ('showkey', '1737')]

Finally, we pass the resulting list to the dict() constructor:

>>> dict([('season', '1'), ('episode', '2'), ('showkey', '1737')])
{'season': '1', 'episode': '2', 'showkey': '1737'}

@Burhan thank you so much, just a quick follow up, why do I lose 'season':1 out of the very first tuple? `new_list[0]` `{'1': 'episode', 'showkey': '1736'}` — Swatty43, Aug 12 '15 at 12:44
Must be some syntax error in your code, when I run it against your sample code it works. — Burhan Khalid, Aug 12 '15 at 13:22

score 1 · Answer 2 · answered Aug 12 '15 at 04:51

I would use a list comprehension, and in that create dicts from the tuple by taking each 2 consecutive elements in it.

Code -

d = [dict((i[j],i[j+1]) for j in range(0,len(i),2)) for i in lt]

Here lt is the list of tuples .

Example -

>>> lt = [('season', '1', 'episode', '1', 'showkey', '1736'),
... ('season', '1', 'episode', '2', 'showkey', '1737'),
... ('season', '1', 'episode', '3', 'showkey', '1738'),
... ('season', '1', 'episode', '4', 'showkey', '1739'),
... ('season', '1', 'episode', '5', 'showkey', '1740'),
... ('season', '1', 'episode', '6', 'showkey', '1741'),
... ('season', '1', 'episode', '7', 'showkey', '1742'),
... ('season', '1', 'episode', '8', 'showkey', '1743'),
... ('season', '1', 'episode', '9', 'showkey', '1744'),
... ('season', '1', 'episode', '10', 'showkey', '1745'),
... ('season', '1', 'episode', '11', 'showkey', '1746'),
... ('season', '1', 'episode', '12', 'showkey', '1747'),
... ('season', '1', 'episode', '13', 'showkey', '1748')]
>>>
>>> d= [dict((i[j],i[j+1]) for j in range(0,len(i),2)) for i in lt]
>>> d
[{'showkey': '1736', 'episode': '1', 'season': '1'}, {'showkey': '1737', 'episode': '2', 'season': '1'}, {'showkey': '1738', 'episode': '3', 'season': '1'}, {'showkey': '1739', 'episode': '4', 'season': '1'}, {'showkey': '1740', 'episode':
 'season': '1'}, {'showkey': '1744', 'episode': '9', 'season': '1'}, {'showkey': '1745', 'episode': '10', 'season': '1'}, {'showkey': '1746', 'episode': '11', 'season': '1'}, {'showkey': '1747', 'episode': '12', 'season': '1'}, {'showkey':

I asked this question a few days ago, and this is a very similar question asked in this thread: https://stackoverflow.com/questions/312443/how-do-you-split-a-list-into-evenly-sized-chunks-in-python — dyao, Aug 12 '15 at 04:56

score 0 · Answer 3 · answered Aug 12 '15 at 04:59

map(lambda datum: dict(zip(datum[::2], datum[1::2])), data)

In slow-mo:

results = []
for datum in data:
    # pick off every alternate item from the tuple, starting with the zeroth.
    keys = datum[::2]
    # pick off every alternate item from the tuple, starting with the oneth.
    values = datum[1::2]
    kv = zip(keys, values)
    new_dict = dict(kv)
    results.append(new_dict)

Please excuse typos, typing this on my phone.

score 0 · Answer 4 · answered Aug 12 '15 at 05:00

x=[('season', '1', 'episode', '1', 'showkey', '1736'),
('season', '1', 'episode', '2', 'showkey', '1737'),
('season', '1', 'episode', '3', 'showkey', '1738'),
('season', '1', 'episode', '4', 'showkey', '1739'),
 ('season', '1', 'episode', '5', 'showkey', '1740'),
  ('season', '1', 'episode','6', 'showkey', '1741'),
 ('season', '1', 'episode', '7', 'showkey', '1742'),
('season', '1', 'episode', '8', 'showkey', '1743'),
('season', '1', 'episode', '9', 'showkey', '1744'),
('season', '1', 'episode', '10', 'showkey', '1745'),
('season', '1', 'episode', '11', 'showkey', '1746'),
('season', '1', 'episode', '12', 'showkey', '1747'),
('season', '1', 'episode', '13', 'showkey', '1748')]
d={}
m=0
for i in x:
    d1={}
    for j in i[::2]:

        d1[j]=i[i.index(j)+1]

    d[m]=d1
    m=m+1

print d

You can create dictionary of dictionary to save all data.

score 0 · Answer 5 · answered Aug 12 '15 at 05:31

inputd = [('season', '1', 'episode', '1', 'showkey', '1736'),
('season', '1', 'episode', '2', 'showkey', '1737'),
('season', '1', 'episode', '3', 'showkey', '1738'),
('season', '1', 'episode', '4', 'showkey', '1739'),
('season', '1', 'episode', '5', 'showkey', '1740'),
('season', '1', 'episode', '6', 'showkey', '1741'),
('season', '1', 'episode', '7', 'showkey', '1742'),
('season', '1', 'episode', '8', 'showkey', '1743'),
('season', '1', 'episode', '9', 'showkey', '1744'),
('season', '1', 'episode', '10', 'showkey', '1745'),
('season', '1', 'episode', '11', 'showkey', '1746'),
('season', '1', 'episode', '12', 'showkey', '1747'),
('season', '1', 'episode', '13', 'showkey', '1748')]


>>> map(dict, map(lambda x: zip(x[::2],x[1::2]), inputd))
[{'season': '1', 'episode': '1', 'showkey': '1736'}, {'season': '1', 'episode': '2', 'showkey': '1737'}, {'season': '1', 'episode': '3', 'showkey': '1738'}, {'season': '1', 'episode': '4', 'showkey': '1739'}, {'season': '1', 'episode': '5', 'showkey': '1740'}, {'season': '1', 'episode': '6', 'showkey': '1741'}, {'season': '1', 'episode': '7', 'showkey': '1742'}, {'season': '1', 'episode': '8', 'showkey': '1743'}, {'season': '1', 'episode': '9', 'showkey': '1744'}, {'season': '1', 'episode': '10', 'showkey': '1745'}, {'season': '1', 'episode': '11', 'showkey': '1746'}, {'season': '1', 'episode': '12', 'showkey': '1747'}, {'season': '1', 'episode': '13', 'showkey': '1748'}]

About python slice

x[::2] - means start through end, skipping ahead 2 places each time
x[1::2] - means, start on index 1 through end, skipping ahead 2 places each time

Python list of tuples with key values to dict

5 Answers5