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cimport cython
cimport numpy as np
import numpy as np
from cython import address
import pandas as pd


@cython.boundscheck(False)
@cython.wraparound(False)
cpdef unsigned char[:,:] get_bytes_arr_view(np.ndarray bytes_arr):
    # 在每个bytes元素最后补零(可自行测试不补零的后果)
    bytes_arr = bytes_arr.astype(str("S%s" % (bytes_arr.dtype.itemsize+1)))
    # 按uint8获取视图
    cdef unsigned char[:,:] bytes_arr_view = bytes_arr.view('uint8').reshape(bytes_arr.size, bytes_arr.dtype.itemsize)
    return bytes_arr_view


def use_case():
    str_arr = np.array(["19:30:11", "19:30:31"])
    cdef np.ndarray time_arr = str_arr.astype(bytes)
    cdef unsigned char[:,:] time_arr_view = get_bytes_arr_view(time_arr)
    cdef unsigned char* time = b""
    # 遍历打印字符串array的元素
    for i in range(time_arr.shape[0]):
        time = address(time_arr_view[i, 0])
        print(time)