从下一个元素减去每个元素的最佳方法是什么

Question

I have very long accumulated list, and i want to subtract each element from the next element. So what's the best way? "The best in terms of readability and speed "

Ex: the list is:

res = [0, 1, 4, 6, 7]  

And the result should be : output=[1, 3, 2, 1]
To clarify, the last element of the output came from output[-1]= res[-1] - res[-2]

So I've tried [xy for x, y in zip (res[::-1], res[::-1][1:])][::-1]

It's so fast, but it's complicated and not readable "I think i will not remember what i did in the next couple of weeks"

PS I am reversing the list using res[::-1]

Answer 1

No need to reverse; just zip the list up into pairs:

>>> [i - j for i, j in zip(res[1:], res[:-1])]
[1, 3, 2, 1]