Say I have the following numpy array:

a = np.array([1,5,5,2,3,6,5,2,5,5,5])

I'm trying to come up with a numpy solution to count the amount of times a given value appears consecutively. So, for example for number 5 I'd like to get:

array([2,1,3])

As it appears consecutively 3 times in the array, with the specified amount of repetitions on each time.

Here is one option adapted from this answer:

def count_consecutive(arr, n):# pad a with False at both sides for edge cases when array starts or ends with nd = np.diff(np.concatenate(([False], arr == n, [False])).astype(int))# subtract indices when value changes from False to True from indices where value changes from True to Falsereturn np.flatnonzero(d == -1) - np.flatnonzero(d == 1)count_consecutive(a, 5)
# array([2, 1, 3])