io.py 文件源码

def getindex(self):
        index_size = ctypes.c_uint64(0)
        index_data = ctypes.POINTER(ctypes.c_uint64)()
        check_call(_LIB.MXDataIterGetIndex(self.handle,
                                           ctypes.byref(index_data),
                                           ctypes.byref(index_size)))
        address = ctypes.addressof(index_data.contents)
        dbuffer = (ctypes.c_uint64* index_size.value).from_address(address)
        np_index = np.frombuffer(dbuffer, dtype=np.uint64)
        return np_index.copy()