Anonimouz:

From what we gather of info on PyTorch documentation we want to use binary cross entropy, and our model will use softmax on the output. Does Binary_cross_entropy use softmax, like Cross_entropy?


No, neither nn.BCELoss nor nn.CrossEntropyLoss expect an output with an applied softmax on it.
nn.BCEWithLogitsLoss as well as nn.CrossEntropyLoss both expect logits (no activation) and are used for a binary classification or multi-label classification, and multi-class classification, repectively.
nn.BCELoss expects probabilities (sigmoid applied on the output) and is numerically less stable than nn.BCEWithLogitsLoss.