例如,bottom[0]是4维的,Shape为100x3x40x60,输出top[0]有同样的Shape,而输入bottom[1] 根据axis的值确定,可以有如下的Shape:
(axis == 0 == -4) 100; 100x3; 100x3x40; 100x3x40x60
(axis == 1 == -3) 3; 3x40; 3x40x60
(axis == 2 == -2) 40; 40x60
(axis == 3 == -1) 60
并且bottom[1] 的Shape为空表示输入的是标量bias,与axis无关。