How to add corresponding elements from lists to python dictionary keys and values respectively

Question

I have 2 lists of the same length and a dictionary

list1 = ['hello', 'goodbye', 'no', 'yes', 'if you say so']
list2 = ['a', 'b', 'c', 'd; e; f', 'g']
listDict = {}

I want to add the corresponding values as keys and values respectively, so the output of the dictionary should be like this (and order should stay the same)

listDict = {'hello':'a', 'goodbye':'b', 'no':'c', 'yes':'d; e; f', 'if you say so':'g'}

I tried

for words in list1:
    for letters in list2:
        listDict[words]=[letters]

but that gives incorrect results (I can't understand them). How could i get the output as described above?

Ashwini Chaudhary · Accepted Answer · 2013-05-13T10:53:40.680

4

use zip():

>>> list1 = ['hello', 'goodbye', 'no', 'yes', 'if you say so']
>>> list2 = ['a', 'b', 'c', 'd; e; f', 'g']
>>> dict(zip(list1,list2))
{'if you say so': 'g', 'yes': 'd; e; f', 'hello': 'a', 'goodbye': 'b', 'no': 'c'}

'yes' 'if you say so' is considered as a single string, use , to separate them:

>>> 'yes' 'if you say so'
'yesif you say so'

Use collections.OrderedDict to preserve order:

>>> from collections import OrderedDict
>>> OrderedDict(zip(list1,list2))

OrderedDict([('hello', 'a'), ('goodbye', 'b'), ('no', 'c'), ('yes', 'd; e; f'), ('if you say so', 'g')])

edited May 13 '13 at 10:53

answered May 13 '13 at 10:43

Ashwini Chaudhary

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I need to keep it in order though as I have to later print the keys and values in the same order... so 'hello':'a', 'goodbye':'b' and so on.. – user2353608 May 13 '13 at 10:51
@user2353608 I've updated my solution. – Ashwini Chaudhary May 13 '13 at 10:54
Sorry I'm beginner, but how come the answer doesn't look like a dictionary anymore? I want it to look like {'hello': 'a', 'goodbye':'b' .... } – user2353608 May 13 '13 at 11:02
@user2353608 It's a subclass of dictionary that preserves order, it's just a representation. – Ashwini Chaudhary May 13 '13 at 11:03
Thanks a lot for your help! – user2353608 May 13 '13 at 11:05

score 1 · Answer 2 · answered May 13 '13 at 10:43

1

list1 = ['hello', 'goodbye', 'no', 'yes' 'if you say so']
list2 = ['a', 'b', 'c', 'd; e; f', 'g']    
listDict = dict(zip(list1, list2))

answered May 13 '13 at 10:43

jvallver

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How to add corresponding elements from lists to python dictionary keys and values respectively

2 Answers2