从两个现有字典中创建新字典

Question

Consider two dictionaries:

dict1 = {'a': 35, 'b': 39, 'c': 20}  # (with the values as integers)

dict2 = {'a': 23, 'c': 12}

I want to obtain the following:

dict_new = {'a': 0.657, 'c': 0.6}  # (with the values as floats, as values of dict2/dict1)

Answer 1

You can get the common keys using dict2.keys() & dict1 and then just do the division:

dict1 = {'a':35, 'b': 39, 'c':20} #(with the values as integers)

dict2 = {'a':23, 'c':12}

d3 = {k: dict2[k] / dict1[k] for k in dict2.keys() & dict1}

If you want the values rounded to three decimal places use round(dict2[k] / dict1[k],3) , if the keys from dict2 should always be in dict1 then you can simply iterate over the items of dict2:

d = {k:v / dict1[k] for k,v in dict2.items()}

Answer 2

dic_new = {}
for key in dic2.keys():
    dic_new[key]=float(dict2[key])/dict1[key]