Updating a list of python dictionaries with a key, value pair from another list

Question

Let\'s say I have the following list of python dictionary:

dict1 = [{\'domain\':\'Ratios\'},{\'domain\':\'Geometry\'}]

and a list like:

Answer 1

>>> l1 = [{'domain':'Ratios'},{'domain':'Geometry'}]
>>> l2 = [3, 6]
>>> for d,num in zip(l1,l2):
        d['count'] = num


>>> l1
[{'count': 3, 'domain': 'Ratios'}, {'count': 6, 'domain': 'Geometry'}]

Another way of doing it, this time with a list comprehension which does not mutate the original:

>>> [dict(d, count=n) for d, n in zip(l1, l2)]
[{'count': 3, 'domain': 'Ratios'}, {'count': 6, 'domain': 'Geometry'}]

Answer 2

Using list comprehension will be the pythonic way to do it.

[data.update({'count': list1[index]}) for index, data in enumerate(dict1)]

The dict1 will be updated with the corresponding value from list1.

Answer 3

You can do this:

# list index
l_index=0

# iterate over all dictionary objects in dict1 list
for d in dict1:

    # add a field "count" to each dictionary object with
    # the appropriate value from the list
    d["count"]=list1[l_index]

    # increase list index by one
    l_index+=1

---

This solution doesn't create a new list. Instead, it updates the existing dict1 list.

Answer 4

You could do this:

for i, d in enumerate(dict1):
    d['count'] = list1[i]