I have a list of dictionary objects (read from csv) that I want to sort. E.g.
l_data.sort(key=lamdba x: (x['fname'], x['lname']))
Now I want to make the code more flexible, and want to sort on the keys based on the input, something like:
def sort_data(l_data, keys):
l_data.sort(key=lambda x: (x[d] for d in keys))
... ...
And I get the following error:
TypeError: unorderable types: generator() < generator()
(x[d] for d in keys) is a generator expression (produces generator object). If you want to make a tuple, wrap that generator expression with tuple(...):
def sort_data(l_data, keys):
l_data.sort(key=lambda x: tuple(x[d] for d in keys))
# code
Though your code can be greatly simplified using operator.itemgetter:
from operator import itemgetter
def sort_data(l_data, keys):
l_data.sort(key=itemgetter(*keys))
# code
You are trying to sort by the generator x[d] for d in keys, the output of the generator needs to be converted to a tuple first.
See here
