• 计算量小的时候numba反而不如原生python
• numba使用nopython模式需要函数内所有对象都支持nopython

def sum(arr):
    s_time = time.time()
    m = arr.shape[0]
    result = 0.0
    for i in range(m):
        result += arr[i]
    e_time = time.time()
    return (e_time-s_time)