Converting list to torch tensor

I am trying to convert list to torch tensor. However, it shows an error len() of unsized object.

torch.tensor(a, dtype=torch.float64)

len(a) is 11.

Thank you!

Could you post how a is defined?

Hello! I defined a = cvqnn_layers_all(L, M), where cvqnn_layers_all(n_layers, n_wires, seed=None) Creates a list of all eleven parameter arrays for CVNeuralNetLayers().
Actually my aim was to convert 11 parameters of cvqnn_layers_all to tensors

Can you print a and show?

[tensor([[2.66190161, 4.0582724 , 2.74944154]], requires_grad=True),
tensor([[5.60317502, 6.0548717 , 2.40923412]], requires_grad=True),
tensor([[4.97455513, 3.32314479, 3.56912924]], requires_grad=True),
tensor([[0.22408932, 0.04843122, 0.05791405]], requires_grad=True),
tensor([[5.46644755, 6.14884039, 5.02126135]], requires_grad=True),
tensor([[2.89956035, 4.90420945, 0.74314013]], requires_grad=True),
tensor([[4.02074236, 0.90071527, 5.93552986]], requires_grad=True),
tensor([[3.27886971, 2.60539781, 1.66225193]], requires_grad=True),
tensor([[-0.02421495, 0.15143913, -0.03330574]], requires_grad=True),
tensor([[3.88071828, 3.84591085, 3.87631062]], requires_grad=True),
tensor([[0.00473648, 0.01549474, 0.03781625]], requires_grad=True)]

You can use cat to concatenate them.

b = torch.cat(a, 0)
print(b)
# Output
tensor([[ 2.6619e+00,  4.0583e+00,  2.7494e+00],
        [ 5.6032e+00,  6.0549e+00,  2.4092e+00],
        [ 4.9746e+00,  3.3231e+00,  3.5691e+00],
        [ 2.2409e-01,  4.8431e-02,  5.7914e-02],
        [ 5.4664e+00,  6.1488e+00,  5.0213e+00],
        [ 2.8996e+00,  4.9042e+00,  7.4314e-01],
        [ 4.0207e+00,  9.0072e-01,  5.9355e+00],
        [ 3.2789e+00,  2.6054e+00,  1.6623e+00],
        [-2.4215e-02,  1.5144e-01, -3.3306e-02],
        [ 3.8807e+00,  3.8459e+00,  3.8763e+00],
        [ 4.7365e-03,  1.5495e-02,  3.7816e-02]], grad_fn=<CatBackward0>)