Method edges

python/dgl/heterograph.py:2157–2242

Return an edge view One can use it for: 1. Getting the edges for a single edge type. In this case, it can take the following optional arguments: - form : str, optional The return form, which can be one of the following: -

(self)

    @property
    def edges(self):
        """Return an edge view

        One can use it for:

        1. Getting the edges for a single edge type. In this case, it can take the
           following optional arguments:

            - form : str, optional
                  The return form, which can be one of the following:

                  - ``'uv'`` (default): The returned result is a 2-tuple of 1D tensors
                    :math:`(U, V)`, representing the source and destination nodes of all edges.
                    For each :math:`i`, :math:`(U[i], V[i])` forms an edge.
                  - ``'eid'``: The returned result is a 1D tensor :math:`EID`, representing
                    the IDs of all edges.
                  - ``'all'``: The returned result is a 3-tuple of 1D tensors :math:`(U, V, EID)`,
                    representing the source nodes, destination nodes and IDs of all edges.
                    For each :math:`i`, :math:`(U[i], V[i])` forms an edge with ID :math:`EID[i]`.
            - order : str, optional
                  The order of the returned edges, which can be one of the following:

                  - ``'eid'`` (default): The edges are sorted by their IDs.
                  - ``'srcdst'``: The edges are sorted first by their source node IDs and then
                    by their destination node IDs to break ties.
            - etype : str or tuple of str, optional
                  The edge type for query, which can be an edge type (str) or a canonical edge
                  type (3-tuple of str). When an edge type appears in multiple canonical edge
                  types, one must use a canonical edge type. If the graph has multiple edge
                  types, one must specify the argument. Otherwise, it can be omitted.
        2. Setting/getting features for all edges of a single edge type. To set/get a feature
           ``feat`` for edges of type ``etype`` in a graph ``g``, one can use
           ``g.edges[etype].data[feat]``.

        Examples
        --------
        The following example uses PyTorch backend.

        >>> import dgl
        >>> import torch

        **Get the Edges for a Single Edge Type**

        Create a graph with a single edge type.

        >>> g = dgl.graph((torch.tensor([1, 0, 0]), torch.tensor([1, 1, 0])))
        >>> g.edges()
        (tensor([1, 0, 0]), tensor([1, 1, 0]))

        Specify a different value for :attr:`form` and :attr:`order`.

        >>> g.edges(form='all', order='srcdst')
        (tensor([0, 0, 1]), tensor([0, 1, 1]), tensor([2, 1, 0]))

        For a graph of multiple edge types, it is required to specify the edge type in query.

        >>> hg = dgl.heterograph({
        ...     ('user', 'follows', 'user'): (torch.tensor([0, 1]), torch.tensor([1, 2])),