如题，调试完毕之后 更换图片进行检测 出现问题
Attempted to access boxes(:,-1); index must be a positive integer or logical.
Error in ==> reduceboxes at 16
maxc = max(boxes(:,end-1));
Error in ==> demo>test at 34
showboxes(im, reduceboxes(model, boxes(top,:)))
具体应该怎么进行调试，急求！尽可能详细！