Question

So I have this:

a = [[4, 8], [5, 6, 9, 10], [13]]

I want to get the difference (subtraction) between:

4 - 5 = a[0][0] - a[1][0]

4 - 6 = a[0][0] - a[1][1]

4 - 9 = a[0][0] - a[1][2]

4 - 10 = a[0][0] - a[1][3]

and then move on to the 8:

8 - 5 = a[0][1] - a[1][0]

8 - 6 = a[0][1] - a[1][1]

...

And so on for all the sub-lists

Any ideas?

EDIT: The other comparisons would look like this:

5 - 13 = a[1][0] - a[2][0]

6 - 13 = a[1][1] - a[2][0]

9 - 13 = a[1][2] - a[2][0]

10 - 13 = a[1][3] - a[2][0]

And because this is the second to last list, then it stops.

I’m trying to implement the Quine-McCluskey method to minimize logic expressions.

Answer 1

Assuming that after finishing a[0][1] - a[1][x] you want to continue with a[0][0] - a[2][0], and then eventually also do a[1][0] - a[2][0] etc.:

result = []
for i, sub_x in enumerate(a[:-1]):
    for sub_y in a[i+1:]:
        for x in sub_x:
            result.append([x - y for y in sub_y])

>>> result
[[-1, -2, -5, -6], [3, 2, -1, -2], [-9], [-5], [-8], [-7], [-4], [-3]]

As a list comprehension:

[[x - y for y in sub_y]
     for i, sub_x in enumerate(a[:-1]) for sub_y in a[i+1:] for x in sub_x]