Rwightman / gen-efficientnet-pytorch : Could not export Python function call

[ynjiun]

Hi

I am impressed by your work on Rwightman / gen-efficientnet-pytorch.

I try to export your model to onnx as following:

x = torch.rand(1, 3, 352, 1216)
torch.onnx.export(net, x, "./sqnet_3566.onnx")
print("export onnx successfully!")

But I encountered the following error message:

Using cache found in /home/paul/.cache/torch/hub/rwightman_gen-efficientnet-pytorch_master
/home/paul/.cache/torch/hub/rwightman_gen-efficientnet-pytorch_master/geffnet/conv2d_layers.py:47: TracerWarning: Converting a tensor to a Python boolean might cause the trace to be incorrect. We can't record the data flow of Python values, so this value will be treated as a constant in the future. This means that the trace might not generalize to other inputs!
  return max((-(i // -s) - 1) * s + (k - 1) * d + 1 - i, 0)
/home/paul/pytorch/AdaBins/models/layers.py:19: TracerWarning: Converting a tensor to a Python index might cause the trace to be incorrect. We can't record the data flow of Python values, so this value will be treated as a constant in the future. This means that the trace might not generalize to other inputs!
  embeddings = embeddings + self.positional_encodings[:embeddings.shape[2], :].T.unsqueeze(0)
Traceback (most recent call last):
  File "rk3566Test.py", line 273, in <module>
    export_pytorch_model()
  File "rk3566Test.py", line 55, in export_pytorch_model
    torch.onnx.export(net, x, "./sqnet_3566.onnx")
  File "/home/paul/rknn2/lib/python3.6/site-packages/torch/onnx/__init__.py", line 208, in export
    custom_opsets, enable_onnx_checker, use_external_data_format)
  File "/home/paul/rknn2/lib/python3.6/site-packages/torch/onnx/utils.py", line 92, in export
    use_external_data_format=use_external_data_format)
  File "/home/paul/rknn2/lib/python3.6/site-packages/torch/onnx/utils.py", line 530, in _export
    fixed_batch_size=fixed_batch_size)
  File "/home/paul/rknn2/lib/python3.6/site-packages/torch/onnx/utils.py", line 384, in _model_to_graph
    fixed_batch_size=fixed_batch_size, params_dict=params_dict)
  File "/home/paul/rknn2/lib/python3.6/site-packages/torch/onnx/utils.py", line 188, in _optimize_graph
    graph = torch._C._jit_pass_onnx(graph, operator_export_type)
  File "/home/paul/rknn2/lib/python3.6/site-packages/torch/onnx/__init__.py", line 241, in _run_symbolic_function
    return utils._run_symbolic_function(*args, **kwargs)
  File "/home/paul/rknn2/lib/python3.6/site-packages/torch/onnx/utils.py", line 791, in _run_symbolic_function
    return symbolic_fn(g, *inputs, **attrs)
  File "/home/paul/rknn2/lib/python3.6/site-packages/torch/onnx/symbolic_helper.py", line 128, in wrapper
    args = [_parse_arg(arg, arg_desc) for arg, arg_desc in zip(args, arg_descriptors)]
  File "/home/paul/rknn2/lib/python3.6/site-packages/torch/onnx/symbolic_helper.py", line 128, in <listcomp>
    args = [_parse_arg(arg, arg_desc) for arg, arg_desc in zip(args, arg_descriptors)]
  File "/home/paul/rknn2/lib/python3.6/site-packages/torch/onnx/symbolic_helper.py", line 81, in _parse_arg
    "', since it's not constant, please try to make "
RuntimeError: Failed to export an ONNX attribute 'onnx::Cast', since it's not constant, please try to make things (e.g., kernel size) static if possible

I did change the _EXPORTABLE flag to True in config.py as following:

# Set to True if exporting a model with Same padding via ONNX
_EXPORTABLE = True

Is this the right way to do it? or I miss something else? Could you please help? Thanks a lot.