def METHOD_NAME(arrA, arrB):
    """compute relative vector length difference"""
    rel_arr = np.zeros(arrA.shape)
    idxNoneZeros = np.where(arrB != 0)
    idxZeros = np.where(arrB == 0)
    rel_arr[idxNoneZeros] = np.absolute(
        np.absolute(arrA[idxNoneZeros]) / np.absolute(arrB[idxNoneZeros]))
    return rel_arr