torch_geometric.nn.conv.SignedConv

class SignedConv(in_channels: int, out_channels: int, first_aggr: bool, bias: bool = True, **kwargs)[source]

Bases: MessagePassing

The signed graph convolutional operator from the “Signed Graph Convolutional Network” paper.

\[ \begin{align}\begin{aligned}\mathbf{x}_v^{(\textrm{pos})} &= \mathbf{\Theta}^{(\textrm{pos})} \left[ \frac{1}{|\mathcal{N}^{+}(v)|} \sum_{w \in \mathcal{N}^{+}(v)} \mathbf{x}_w , \mathbf{x}_v \right]\\\mathbf{x}_v^{(\textrm{neg})} &= \mathbf{\Theta}^{(\textrm{neg})} \left[ \frac{1}{|\mathcal{N}^{-}(v)|} \sum_{w \in \mathcal{N}^{-}(v)} \mathbf{x}_w , \mathbf{x}_v \right]\end{aligned}\end{align} \]

if first_aggr is set to True, and

\[ \begin{align}\begin{aligned}\mathbf{x}_v^{(\textrm{pos})} &= \mathbf{\Theta}^{(\textrm{pos})} \left[ \frac{1}{|\mathcal{N}^{+}(v)|} \sum_{w \in \mathcal{N}^{+}(v)} \mathbf{x}_w^{(\textrm{pos})}, \frac{1}{|\mathcal{N}^{-}(v)|} \sum_{w \in \mathcal{N}^{-}(v)} \mathbf{x}_w^{(\textrm{neg})}, \mathbf{x}_v^{(\textrm{pos})} \right]\\\mathbf{x}_v^{(\textrm{neg})} &= \mathbf{\Theta}^{(\textrm{pos})} \left[ \frac{1}{|\mathcal{N}^{+}(v)|} \sum_{w \in \mathcal{N}^{+}(v)} \mathbf{x}_w^{(\textrm{neg})}, \frac{1}{|\mathcal{N}^{-}(v)|} \sum_{w \in \mathcal{N}^{-}(v)} \mathbf{x}_w^{(\textrm{pos})}, \mathbf{x}_v^{(\textrm{neg})} \right]\end{aligned}\end{align} \]

otherwise. In case first_aggr is False, the layer expects x to be a tensor where x[:, :in_channels] denotes the positive node features \(\mathbf{X}^{(\textrm{pos})}\) and x[:, in_channels:] denotes the negative node features \(\mathbf{X}^{(\textrm{neg})}\).

Parameters:

  • in_channels (int) – Size of each input sample, or -1 to derive the size from the first input(s) to the forward method.

  • out_channels (int) – Size of each output sample.

  • first_aggr (bool) – Denotes which aggregation formula to use.

  • bias (bool, optional) – If set to False, the layer will not learn an additive bias. (default: True)

  • **kwargs (optional) – Additional arguments of torch_geometric.nn.conv.MessagePassing.

Shapes:

  • input: node features \((|\mathcal{V}|, F_{in})\) or \(((|\mathcal{V_s}|, F_{in}), (|\mathcal{V_t}|, F_{in}))\) if bipartite, positive edge indices \((2, |\mathcal{E}^{(+)}|)\), negative edge indices \((2, |\mathcal{E}^{(-)}|)\)

  • outputs: node features \((|\mathcal{V}|, F_{out})\) or \((|\mathcal{V_t}|, F_{out})\) if bipartite

forward(x: Union[Tensor, Tuple[Tensor, Tensor]], pos_edge_index: Union[Tensor, SparseTensor], neg_edge_index: Union[Tensor, SparseTensor])[source]

Runs the forward pass of the module.

reset_parameters()[source]

Resets all learnable parameters of the module.