Retrieving array elements with an array of frequencies in NumPy

Question

I have an array of numbers, a. I have a second array, b, specifying how many times I want to retrieve the corresponding element in a. How

Answer 1

here's one way to do it:

res = []
for i in xrange(len(b)):
    for j in xrange(b[i]):
        out.append(a[i])

res = np.array(res)  # optional