I have this list:
list = [("a", 1), ("b", 2), ("a", 3), ("b", 1), ("a", 2), ("c", 1)]
I want to convert it into a dictionary which looks like:
{'a': [1, 3, 2], 'b': [2, 1], 'c': [1]}
I tried this:
for key, value is list:
if key in list_dictionary:
dict(list_dictionary)
else:
list_dictionary[key] = value
and the output came:
{'a': 1, 'b': 2, 'c': 1}
What should I do?
The problem is that your value would be covered.You could use defaultdict:
from collections import defaultdict
l = [("a", 1), ("b", 2), ("a", 3), ("b", 1), ("a", 2), ("c", 1)]
r = defaultdict(list)
for key, value in l:
r[key].append(value)
print(r)
This gave me:
defaultdict(<class 'list'>, {'a': [1, 3, 2], 'b': [2, 1], 'c': [1]})
below
from collections import defaultdict
data = defaultdict(list)
lst = [("a", 1), ("b", 2), ("a", 3), ("b", 1), ("a", 2), ("c", 1)]
for entry in lst:
data[entry[0]].append(entry[1])
print(data)
My approach is bit different, probably you can checkout this answer too:
user_list = [("a", 1), ("b", 2), ("a", 3), ("b", 1), ("a", 2), ("c", 1)]
final = {}
for item in user_list:
final.update(
{
item[0]: [item[1]] + final[item[0]] if final.get(item[0]) else [item[1]]
}
)
print(final)
output: {'a': [2, 3, 1], 'b': [1, 2], 'c': [1]}
