Create OrderedDict from dict with values of list type (in the order of list's values)

Question

It is a bit hard for me to explain it in words, so I'll show an example:

What I have (data is a dict instance):

data = {'a':[4,5,3], 'b':[1,0,2], 'c':[6,7,8]}

What I need (ordered_data is an OrderedDict instance):

ordered_data = {'b':[0,1,2], 'a':[3,4,5], 'b':[6,7,8]}

The order of keys should be changed with respect to order of items in nested lists

Answer 1

tmp = {k:sorted(v) for k,v in data.items()}
ordered_data = OrderedDict((k,v) for k,v in sorted(tmp.items(), key=lambda i: i[1]))

First sort the values. If you don't need the original data, it's OK to do this in place, but I made a temporary variable.

key is a function that returns a key to be sorted on. In this case, the key is the second element of the item tuple (the list), and since lists are comparable, that's good enough.