# Source code for dgllife.model.model_zoo.weave_predictor

```
# -*- coding: utf-8 -*-
#
# Copyright Amazon.com, Inc. or its affiliates. All Rights Reserved.
# SPDX-License-Identifier: Apache-2.0
#
# Weave
# pylint: disable= no-member, arguments-differ, invalid-name
import torch.nn as nn
import torch.nn.functional as F
from ..gnn import WeaveGNN
from ..readout import WeaveGather
__all__ = ['WeavePredictor']
# pylint: disable=W0221
[docs]class WeavePredictor(nn.Module):
r"""Weave for regression and classification on graphs.
Weave is introduced in `Molecular Graph Convolutions: Moving Beyond Fingerprints
<https://arxiv.org/abs/1603.00856>`__
Parameters
----------
node_in_feats : int
Size for the input node features.
edge_in_feats : int
Size for the input edge features.
num_gnn_layers : int
Number of GNN (Weave) layers to use. Default to 2.
gnn_hidden_feats : int
Size for the hidden node and edge representations.
Default to 50.
gnn_activation : callable
Activation function to be used in GNN (Weave) layers.
Default to ReLU.
graph_feats : int
Size for the hidden graph representations. Default to 50.
gaussian_expand : bool
Whether to expand each dimension of node features by
gaussian histogram in computing graph representations.
Default to True.
gaussian_memberships : list of 2-tuples
For each tuple, the first and second element separately
specifies the mean and std for constructing a normal
distribution. This argument comes into effect only when
``gaussian_expand==True``. By default, we set this to be
``[(-1.645, 0.283), (-1.080, 0.170), (-0.739, 0.134),
(-0.468, 0.118), (-0.228, 0.114), (0., 0.114),
(0.228, 0.114), (0.468, 0.118), (0.739, 0.134),
(1.080, 0.170), (1.645, 0.283)]``.
readout_activation : callable
Activation function to be used in computing graph
representations out of node representations. Default to Tanh.
n_tasks : int
Number of tasks, which is also the output size. Default to 1.
"""
def __init__(self,
node_in_feats,
edge_in_feats,
num_gnn_layers=2,
gnn_hidden_feats=50,
gnn_activation=F.relu,
graph_feats=128,
gaussian_expand=True,
gaussian_memberships=None,
readout_activation=nn.Tanh(),
n_tasks=1):
super(WeavePredictor, self).__init__()
self.gnn = WeaveGNN(node_in_feats=node_in_feats,
edge_in_feats=edge_in_feats,
num_layers=num_gnn_layers,
hidden_feats=gnn_hidden_feats,
activation=gnn_activation)
self.node_to_graph = nn.Sequential(
nn.Linear(gnn_hidden_feats, graph_feats),
readout_activation,
nn.BatchNorm1d(graph_feats)
)
self.readout = WeaveGather(node_in_feats=graph_feats,
gaussian_expand=gaussian_expand,
gaussian_memberships=gaussian_memberships,
activation=readout_activation)
self.predict = nn.Linear(graph_feats, n_tasks)
[docs] def forward(self, g, node_feats, edge_feats):
"""Graph-level regression/soft classification.
Parameters
----------
g : DGLGraph
DGLGraph for a batch of graphs.
node_feats : float32 tensor of shape (V, node_in_feats)
Input node features. V for the number of nodes.
edge_feats : float32 tensor of shape (E, edge_in_feats)
Input edge features. E for the number of edges.
Returns
-------
float32 tensor of shape (G, n_tasks)
Prediction for the graphs in the batch. G for the number of graphs.
"""
node_feats = self.gnn(g, node_feats, edge_feats, node_only=True)
node_feats = self.node_to_graph(node_feats)
g_feats = self.readout(g, node_feats)
return self.predict(g_feats)
```