Thanks @jamesrequa
I try git checkout tag 1.0.5 and remove the symlink, I make sure the fastai.version is 1.0.5 as well, I still get NaN though. If you read the thread below, it seems that it was cause by one of the transformation, but I cannot go deeper to debug effective for now as I am not familiar with the source yet…
This is another thread that discussing this issue.