Equivalent of Numpy.argsort() in basic python? [duplicate]

There is no built-in function, but it’s easy to assemble one out of the terrific tools Python makes available:

def argsort(seq):
    # http://stackoverflow.com/questions/3071415/efficient-method-to-calculate-the-rank-vector-of-a-list-in-python
    return sorted(range(len(seq)), key=seq.__getitem__)

x = [5,2,1,10]

print(argsort(x))
# [2, 1, 0, 3]

It works on Python array.arrays the same way:

import array
x = array.array('d', [5, 2, 1, 10])
print(argsort(x))
# [2, 1, 0, 3]