expand unsupported

[jaybdub]

expand broadcasts tensors along specified dimensions.

https://pytorch.org/docs/stable/tensors.html

[jaybdub]

Following converter seems to work

@torch2trt.tensorrt_converter('torch.Tensor.expand')
def convert_expand(ctx):
    input = ctx.method_args[0]
    sizes = ctx.method_args[1:]
    output = ctx.method_return
    
    inshape = tuple(input.shape)[1:]
    shape = sizes[1:] # exclude batch
    ndim = len(shape)
    start = tuple([0]*ndim)
    stride = tuple([int(i == o) for i, o in zip(inshape, shape)])  # stride == 1 if dimensions match, 0 otherwise
    
    layer = ctx.network.add_slice(input._trt, start, shape, stride)
    
    output._trt = layer.get_output(0)
    print(output._trt.shape)

[jaybdub]

converter now added in master as of #487

[DaweiLi-Topcon]

@jaybdub Hi John, I failed to pass this module, Here is the log I met.
File "/XXXX/networks.py", line 525, in forward
levels = levels.expand((xsize + [len(self.levels)]))
File "/XXXX/venv/lib/python3.6/site-packages/torch2trt-0.3.0-py3.6.egg/torch2trt/torch2trt.py", line 300, in wrapper
converter"converter"
File "/XXXX/lib/python3.6/site-packages/torch2trt-0.3.0-py3.6.egg/torch2trt/converters/expand.py", line 17, in convert_expand
layer = ctx.network.add_slice(input._trt, start, shape, stride)
AttributeError: 'Tensor' object has no attribute '_trt'

in the module of convert_expand, how can we change input to input._trt?