Question

If I have a list:

my_list = [3,2,2,3,4,1,3,4]

and a tuple

my_tuple = (3,5)

What’s the best way of replacing elements in my_list using the tuple:

result = [5,2,2,5,4,1,5,4]

e.g.

for item in my_list:
    if(item == my_tuple[0]):
        item = my_tuple[1]

More generally, I would have a list of lists, and a list of tuples, and I would like to apply each of the tuples to each of the lists within the list of lists.

Answer 1

The more natural data structure for my_tuple is a dictionary. Consider something like this and use the .get() method:

>>> my_lists = [[3,2,2,3,4,1,3,4], [1,2,3,4,5,6]]
>>> my_tuple_list = [(3,5), (6, 7)]
>>> my_dict = dict(my_tuple_list)
>>> my_dict
{3: 5, 6: 7}
>>> my_lists = [[my_dict.get(x,x) for x in somelist] for somelist in my_lists]
>>> my_lists
[[5, 2, 2, 5, 4, 1, 5, 4], [1, 2, 5, 4, 5, 7]]