Address #4584, it works end 2 end so far. But some unused tensors got exported, too. Will fix it soon.

@ezyang, the unused stuff got removed, ready for review. :-)

@onnxbot retest this please

Please ignore the failed onnx-fb-universe CI, I already updated the expected files in onnxbot/onnx-fb-universe#268

CC @linkerzhang

I'm on the hook for finishing this.

After reading this post, I tried to install pytorch by source and the onnx does work on instanceNorm2D now. Thanks.

However, I encountered some other problems. I trained some pytorch model using the pytorch version installed through http://pytorch.org/. I was able to save the trained model as .pth file and load it back in successfully by doing the following:

model = myNet(parameters...) model.load_state_dict(torch.load('xxx.pth'))

However, after I install the latest pytorch from source. The load_state_dict is reporting errors:

File "/anaconda2/lib/python2.7/site-packages/torch/nn/modules/module.py", line 528, in load_state_dict
.format(name))
KeyError: 'unexpected key "pre_model.1.running_mean" in state_dict'

I did the following to check which layer was causing the problem
model1 = myNet(parameters...)
model2 = torch.load('xxx.pth')

for name, param in model2.items():
print(name)

for name, param in model1.state_dict().items():
print(name)

I found that for the instanceNorm2D layers, model2 contains xxx.running_mean and xxx.running_var, but not model1. Any idea what I should do?

Another question:
If I use the instanceNorm2D layer with affine=True, nn.InstanceNorm2d(ngf,affine=True), then I get the following problem when doing torch.onnx.export

torch.onnx.export(model, (dummy_input, dummy_input), MODEL_DIR + "eye_G.proto", verbose=True)
File "/anaconda2/lib/python2.7/site-packages/torch/onnx/init.py", line 83, in export
_export(model, args, f, export_params, verbose, training, input_names, output_names)
File "/anaconda2/lib/python2.7/site-packages/torch/onnx/init.py", line 138, in _export
_optimize_trace(trace, aten)
File "/anaconda2/lib/python2.7/site-packages/torch/onnx/init.py", line 94, in _optimize_trace
torch._C._jit_pass_onnx(trace, aten)
File "/anaconda2/lib/python2.7/site-packages/torch/onnx/init.py", line 180, in _run_symbolic_method
return symbolic_fn(*args)
File "/anaconda2/lib/python2.7/site-packages/torch/onnx/init.py", line 396, in symbolic
symbolic_output = symbolic_fn(g, *symbolic_args, **kwargs)
File "/anaconda2/lib/python2.7/site-packages/torch/onnx/symbolic.py", line 552, in instance_norm
if not weight:
RuntimeError: bool value of Tensor with more than one value is ambiguous

If I do nn.InstanceNorm2d(ngf,affine=False) or nn.InstanceNorm2d(ngf), then the export will succeed. Please help. Thanks.