Why is results from main.py and results of trtexec engine different

[TwinkleYR]

the results of trtexec engine has problem as below:
[ 0.7829 -0.24191 12.481 ... 0.0031602 0.0011548 0.0015741]
Device:
<pycuda._driver.DeviceAllocation object at 0x7f7a72775170>]
Traceback (most recent call last):
File "/home/wangyr/TensorRT/yolov5-tensorrt/main.py", line 399, in
trt_result = profile_trt(build_engine(onnx_path, using_half), batch_size, 10, 100)
File "/home/wangyr/TensorRT/yolov5-tensorrt/main.py", line 327, in profile_trt
boxes = np.array(yolo_outputs[1].host).reshape(batch_size, -1, 4)[0, 0:num_det, 0:4]
IndexError: list index out of range

the results of main.py is correct