Python – Cross Pattern Pairs in List

When it is required to display cross pattern pairs in list, a list comprehension and the multiplication operator are used to create all possible products between elements of two lists.

What is Cross Pattern Pairs?

Cross pattern pairs refer to multiplying each element from the first list with every element from the second list, creating a Cartesian product of multiplications.

Example

my_list_1 = [14, 35, 26]
my_list_2 = [36, 24, 12]

print("The first list is :")
print(my_list_1)
print("The second list is :")
print(my_list_2)

result = [i * j for j in my_list_1 for i in my_list_2]

print("The result is :")
print(result)

Output

The first list is :
[14, 35, 26]
The second list is :
[36, 24, 12]
The result is :
[504, 336, 168, 1260, 840, 420, 936, 624, 312]

How It Works

The list comprehension [i * j for j in my_list_1 for i in my_list_2] works as follows:

• For each element j in my_list_1 (14, 35, 26)

• Multiply it with each element i in my_list_2 (36, 24, 12)

• The pattern creates: 14×36, 14×24, 14×12, then 35×36, 35×24, 35×12, then 26×36, 26×24, 26×12

Alternative Method Using Nested Loops

my_list_1 = [14, 35, 26]
my_list_2 = [36, 24, 12]

result = []
for j in my_list_1:
    for i in my_list_2:
        result.append(i * j)

print("Cross pattern result:")
print(result)

Cross pattern result:
[504, 336, 168, 1260, 840, 420, 936, 624, 312]

Conclusion

Cross pattern pairs multiply each element from one list with every element from another list. List comprehension provides a concise way to achieve this Cartesian product multiplication.