Checking for key values in dictionary

Question

dic1 = {
    'a':2,
    'b':3
}

dic2 = {
    'a':2,
    'b':3,
    'c':5
}
...

My particular question is more of a syntax in python question for my own satisfaction. Suppose you have a bunch of dictionaries and you want to add up all attributes a,b, and c which may not exist... My current code is kind of bulky and I'm not a fan of a bunch of if elif statements...

if 'a' in dicX:
   total+=dicX['a']
if 'b' in dicX:
   total+=dicX['b']
if 'c' in dicX:
   total+=dicX['c']

Can anyone recommend a better single line way of doing this? Or just a cleaner way to do this?

* Also see: https://stackoverflow.com/questions/19461747/sum-corresponding-elements-of-multiple-python-dictionaries — l'L'l, Jun 01 '17 at 03:28

score 0 · Accepted Answer · answered Jun 01 '17 at 03:20

0

{k : (dic1[k] if k in dic1 else 0) + (dic2[k] if k in dic2 else 0) 
 for k in dic1.keys() | dic2.keys()}
#{'b': 6, 'c': 5, 'a': 4}

answered Jun 01 '17 at 03:20

DYZ

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Not a bad suggestion, still long just reformatted, granted there may not be a cleaner way to do it... But thanks! – Sebastian Łącki Jun 01 '17 at 03:32

Checking for key values in dictionary

1 Answers1