切片与索引

Question

I thought Python (numpy) is zero indexing, but when I slice [:0] it returns empty array. I thought I'm saying slice from zero to zero but clearly I am not.

If instead I use A[1] it returns the position 1 element of by zero-indexing.

Answer 1

When using slice it excludes the endpoint, just like in range(a, b) = a..(b-1)

Though when you do list[:1] it should return [list[0]] , not an empty array. Thus I suspect that your array is empty from the beginning.

Reference