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来自 pytorch 1.1.0 的发布亮点。似乎最新的 JIT 编译器现在支持 Dict 类型。（来源：https ://jaxenter.com/pytorch-1-1-158332.html ）

TorchScript 中的字典和列表支持：列表和字典类型的行为类似于 Python 列表和字典。

不幸的是，我找不到使这种改进正常工作的方法。以下代码是将特征金字塔网络 (FPN) 导出到 tensorboard 的简单示例，它使用 JIT 编译器：

from collections import OrderedDict

import torch
import torchvision
from torch.utils.tensorboard import SummaryWriter

torchWriter = SummaryWriter(log_dir=".tensorboard/example1")

m = torchvision.ops.FeaturePyramidNetwork([10, 20, 30], 5)
# get some dummy data
x = OrderedDict()
x['feat0'] = torch.rand(1, 10, 64, 64)
x['feat2'] = torch.rand(1, 20, 16, 16)
x['feat3'] = torch.rand(1, 30, 8, 8)
# compute the FPN on top of x
output = m.forward(x)
print([(k, v.shape) for k, v in output.items()])

torchWriter.add_graph(m, input_to_model=x)

当我运行它时，出现以下错误：

Traceback (most recent call last):
  File "/home/shared/virtualenv/dl-torch/lib/python3.7/site-packages/torch/utils/tensorboard/_pytorch_graph.py", line 276, in graph
    trace, _ = torch.jit.get_trace_graph(model, args)
  File "/home/shared/virtualenv/dl-torch/lib/python3.7/site-packages/torch/jit/__init__.py", line 231, in get_trace_graph
    return LegacyTracedModule(f, _force_outplace, return_inputs)(*args, **kwargs)
  File "/home/shared/virtualenv/dl-torch/lib/python3.7/site-packages/torch/nn/modules/module.py", line 493, in __call__
    result = self.forward(*input, **kwargs)
  File "/home/shared/virtualenv/dl-torch/lib/python3.7/site-packages/torch/jit/__init__.py", line 284, in forward
    in_vars, in_desc = _flatten(args)
RuntimeError: Only tuples, lists and Variables supported as JIT inputs, but got collections.OrderedDict

During handling of the above exception, another exception occurred:

Traceback (most recent call last):
  File "/home/peng/git-drone/gate_detection/python/gate_detection/errorcase/tb.py", line 36, in <module>
    torchWriter.add_graph(m, input_to_model=x)
  File "/home/shared/virtualenv/dl-torch/lib/python3.7/site-packages/torch/utils/tensorboard/writer.py", line 534, in add_graph
    self._get_file_writer().add_graph(graph(model, input_to_model, verbose, **kwargs))
  File "/home/shared/virtualenv/dl-torch/lib/python3.7/site-packages/torch/utils/tensorboard/_pytorch_graph.py", line 279, in graph
    _ = model(*args)  # don't catch, just print the error message
  File "/home/shared/virtualenv/dl-torch/lib/python3.7/site-packages/torch/nn/modules/module.py", line 493, in __call__
    result = self.forward(*input, **kwargs)
TypeError: forward() takes 2 positional arguments but 4 were given

从错误消息看来，支持仍在等待中。我可以相信发布亮点吗？或者我没有正确使用 API？

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1 回答 1

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发行说明是准确的，尽管有点模糊。该链接（和官方发行说明）中描述的字典/列表/用户定义的类支持仅适用于TorchScript 编译器（发行说明中有一些代码示例），但SummaryWriter默认情况下将在您的任何模块上运行 TorchScript 跟踪器传递给它，跟踪器只支持张量和张量的列表/元组。

所以解决方法是使用 TorchScript 编译器而不是跟踪器，但这需要：

  1. 访问原始代码
  2. 支持ScriptModuleTensorboard 中的编译输出 ( )

您应该为 (2)提交问题，并且正在进行修复 (1) 的工作，但这在短期内对于该模型 afaik 不起作用。

于 2019-07-03T18:47:41.277 回答