nn.BCELoss, nn.CrossEntropyLoss, BCEWithLogitsLoss
https://cloud.tencent.com/developer/article/1741626
https://cloud.tencent.com/developer/article/1660961
BCELoss是Binary CrossEntropyLoss的缩写,BCELoss CrossEntropyLoss的一个特例,只用于二分类问题,而CrossEntropyLoss可以用于二分类,也可以用于多分类。