libb.diff

diff(x)

Compute one-period difference between consecutive elements.

Parameters:

x (Iterable) – Array of values.

Returns:

Array of differences (first element is None).

Example:

>>> [_ for _ in diff((0, 1, 3, 2, 1, 5, 4))]
[None, 1.0, 2.0, -1.0, -1.0, 4.0, -1.0]