Cartesian product of a dictionary of lists

Question

I\'m trying to write some code to test out the Cartesian product of a bunch of input parameters.

I\'ve looked at itertools, but its product

Answer 1

Ok, thanks @dfan for telling me I was looking in the wrong place. I've got it now:

from itertools import product
def my_product(inp):
    return (dict(zip(inp.keys(), values)) for values in product(*inp.values())

EDIT: after years more Python experience, I think a better solution is to accept kwargs rather than a dictionary of inputs; the call style is more analogous to that of the original itertools.product. Also I think writing a generator function, rather than a function that returns a generator expression, makes the code clearer. So:

def product_dict(**kwargs):
    keys = kwargs.keys()
    vals = kwargs.values()
    for instance in itertools.product(*vals):
        yield dict(zip(keys, instance))

and if you need to pass in a dict, list(product_dict(**mydict)). The one notable change using kwargs rather than an arbitrary input class is that it prevents the keys/values from being ordered, at least until Python 3.6.