weighted_sample_neighbors

paddle.geometric. weighted_sample_neighbors ( row, colptr, edge_weight, input_nodes, sample_size=- 1, eids=None, return_eids=False, name=None ) [source]

Graph Weighted Sample Neighbors API.

This API is mainly used in Graph Learning domain, and the main purpose is to provide high performance of graph weighted-sampling method. For example, we get the CSC(Compressed Sparse Column) format of the input graph edges as row and colptr, so as to convert graph data into a suitable format for sampling, and the input edge_weight should also match the CSC format. Besides, input_nodes means the nodes we need to sample neighbors, and sample_sizes means the number of neighbors and number of layers we want to sample. This API will finally return the weighted sampled neighbors, and the probability of being selected as a neighbor is related to its weight, with higher weight and higher probability.

Parameters

  • row (Tensor) – One of the components of the CSC format of the input graph, and the shape should be [num_edges, 1] or [num_edges]. The available data type is int32, int64.

  • colptr (Tensor) – One of the components of the CSC format of the input graph, and the shape should be [num_nodes + 1, 1] or [num_nodes + 1]. The data type should be the same with row.

  • edge_weight (Tensor) – The edge weight of the CSC format graph edges. And the shape should be [num_edges, 1] or [num_edges]. The available data type is float32.

  • input_nodes (Tensor) – The input nodes we need to sample neighbors for, and the data type should be the same with row.

  • sample_size (int, optional) – The number of neighbors we need to sample. Default value is -1, which means returning all the neighbors of the input nodes.

  • eids (Tensor, optional) – The eid information of the input graph. If return_eids is True, then eids should not be None. The data type should be the same with row. Default is None.

  • return_eids (bool, optional) – Whether to return eid information of sample edges. Default is False.

  • name (str, optional) – Name for the operation (optional, default is None). For more information, please refer to Name.

Returns

  • out_neighbors (Tensor), the sample neighbors of the input nodes.

  • out_count (Tensor), the number of sampling neighbors of each input node, and the shape should be the same with input_nodes.

  • out_eids (Tensor), if return_eids is True, we will return the eid information of the sample edges.

Examples

>>> import paddle

>>> # edges: (3, 0), (7, 0), (0, 1), (9, 1), (1, 2), (4, 3), (2, 4),
>>> #        (9, 5), (3, 5), (9, 6), (1, 6), (9, 8), (7, 8)
>>> row = [3, 7, 0, 9, 1, 4, 2, 9, 3, 9, 1, 9, 7]
>>> colptr = [0, 2, 4, 5, 6, 7, 9, 11, 11, 13, 13]
>>> weight = [0.1, 0.5, 0.2, 0.5, 0.9, 1.9, 2.0, 2.1, 0.01, 0.9, 0,12, 0.59, 0.67]
>>> nodes = [0, 8, 1, 2]
>>> sample_size = 2
>>> row = paddle.to_tensor(row, dtype="int64")
>>> colptr = paddle.to_tensor(colptr, dtype="int64")
>>> weight = paddle.to_tensor(weight, dtype="float32")
>>> nodes = paddle.to_tensor(nodes, dtype="int64")
>>> out_neighbors, out_count = paddle.geometric.weighted_sample_neighbors(row, colptr, weight, nodes, sample_size=sample_size)