在python中查找数字列表的所有组合而不是相同的组合

Question

I would like to find all combinations of my list of numbers without the pair being the same. The code I've written below gives me all combinations. So, I also get [1, 1], [2, 2] and [3, 3], which I'd like to remove.

nr_list = [1, 2, 3]
combinations = []
for a in nr_list:
    for b in nr_list:
        pair = [a, b]
        combinations.append(pair)
print(combinations)

Answer 1

from itertools import permutations
nr_list = [1, 2, 3]
print(list(permutations(nr_list,2)))
# [(1, 2), (1, 3), (2, 1), (2, 3), (3, 1), (3, 2)]

Answer 2

如果pair中的项相等，即if pair[0] != pair[1]:则不要将pair添加到组合中if pair[0] != pair[1]:

Answer 3

Try this code

nr_list = [1, 2, 3]
combinations = []
for a in nr_list:
    for b in nr_list:
        if(a!=b):
            pair = [a, b]
            combinations.append(pair)
print(combinations)