loss function

[Llq201809]

Thank you for your attention. I didn't understand this loss function. Can you give me a analysis?

def box_loss(self,gt_label,gt_offset,pred_offset):
pred_offset = torch.squeeze(pred_offset)
gt_offset = torch.squeeze(gt_offset)
gt_label = torch.squeeze(gt_label)

    #get the mask element which != 0
    unmask = torch.eq(gt_label,0)
    mask = torch.eq(unmask,0)
    #convert mask to dim index
    chose_index = torch.nonzero(mask.data)
    chose_index = torch.squeeze(chose_index)
    #only valid element can effect the loss
    valid_gt_offset = gt_offset[chose_index,:]
    valid_pred_offset = pred_offset[chose_index,:]
    return self.loss_box(valid_pred_offset,valid_gt_offset)*self.box_factor