Hi all, consider this dictionary
users = {'user1':['office-a', 'office-b'],
'user2':['office-b'],
'user3':['office-a','office-c']}
It's a list of users.
For each user there's a list of room it can access to.
Generalizing, a dictionary with a list for each element.
d = {k:list}
I wish to get the same info but "sorted" by room.
In other words, a dictionary that has rooms as keys.
For each room there's a list of users that can access the room.
I've been able to achieve that by
for user in users:
for room in users[user]:
if room in users_by_room:
users_by_room[room].append(user)
else:
users_by_room[room] = []
users_by_room[room].append(user)
And i generalized it in a function like this:
def viceversa(d):
new_d = dict()
for k in d:
for e in d[k]:
if e in new_d:
new_d[e].append(k)
else:
new_d[e] = []
new_d[e].append(k)
return(new_d)
My question is: is there a better way to that?
Maybe by list comprehension?
I was looking to substiture the cicle for e in new_d like this:
[ new_d[e].append(k) if e in new_d else new_d[e].append(k) for e in d[k] ]
but it can't work because 'new_d[e] = []' is missing.
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