Numpy: find index of the elements within range

Question

I have a numpy array of numbers, for example,

a = np.array([1, 3, 5, 6, 9, 10, 14, 15, 56])  

I would like to find all the indexes of the

Answer 1

I thought I would add this because the a in the example you gave is sorted:

import numpy as np
a = [1, 3, 5, 6, 9, 10, 14, 15, 56] 
start = np.searchsorted(a, 6, 'left')
end = np.searchsorted(a, 10, 'right')
rng = np.arange(start, end)
rng
# array([3, 4, 5])