initial ginipath

Initial example file for ginipath

.gitignore

@@ -105,3 +105,30 @@ venv.bak/
 
 *.swp
 *.swo
+examples/pytorch/data/ind.pubmed.y
+examples/pytorch/data/ind.pubmed.x
+examples/pytorch/data/ind.pubmed.ty
+examples/pytorch/data/ind.pubmed.tx
+examples/pytorch/data/ind.pubmed.test.index
+examples/pytorch/data/ind.pubmed.graph
+examples/pytorch/data/ind.pubmed.ally
+examples/pytorch/data/ind.pubmed.allx
+examples/pytorch/data/ind.cora.y
+examples/pytorch/data/ind.cora.x
+examples/pytorch/data/ind.cora.ty
+examples/pytorch/data/ind.cora.tx
+examples/pytorch/data/ind.cora.test.index
+examples/pytorch/data/ind.cora.graph
+examples/pytorch/data/ind.cora.ally
+examples/pytorch/data/ind.cora.allx
+examples/pytorch/data/ind.citeseer.y
+examples/pytorch/data/ind.citeseer.x
+examples/pytorch/data/ind.citeseer.ty
+examples/pytorch/data/ind.citeseer.tx
+examples/pytorch/data/ind.citeseer.test.index
+examples/pytorch/data/ind.citeseer.graph
+examples/pytorch/data/ind.citeseer.ally
+examples/pytorch/data/ind.citeseer.allx
+examples/pytorch/.DS_Store
+examples/.DS_Store
+.DS_Store

examples/pytorch/ginipath.py

+#!/usr/bin/env python3
+# -*- coding: utf-8 -*-
+"""
+Created on Mon Jul  9 13:34:38 2018
+
+@author: ivabruge
+"""
+
+"""
+Graph Attention Networks
+Paper: https://arxiv.org/abs/1710.10903
+Code: https://github.com/PetarV-/GAT
+"""
+
+import networkx as nx
+from dgl.graph import DGLGraph
+import torch
+import torch.nn as nn
+import torch.nn.functional as F
+import argparse
+from dataset import load_data, preprocess_features
+import numpy as np
+
+class NodeReduceModule(nn.Module):
+    def __init__(self, input_dim, num_hidden, num_heads=3, input_dropout=None,
+            attention_dropout=None, act=lambda x: F.softmax(F.leaky_relu(x), dim=0)):
+        super(NodeReduceModule, self).__init__()
+        self.num_heads = num_heads
+        self.input_dropout = input_dropout
+        self.attention_dropout = attention_dropout
+        self.act = act
+        self.fc = nn.ModuleList(
+                [nn.Linear(input_dim, num_hidden, bias=False)
+                    for _ in range(num_heads)])
+        self.attention = nn.ModuleList(
+                [nn.Linear(num_hidden * 2, 1, bias=False) for _ in range(num_heads)])
+
+    def forward(self, msgs):
+        src, dst = zip(*msgs)
+        hu = torch.cat(src, dim=0) # neighbor repr
+        hv = torch.cat(dst, dim=0)
+
+        msgs_repr = []
+
+        # iterate for each head
+        for i in range(self.num_heads):
+            # calc W*hself and W*hneigh
+            hvv = self.fc[i](hv)
+            huu = self.fc[i](hu)
+            # calculate W*hself||W*hneigh
+            h = torch.cat((hvv, huu), dim=1)
+            a = self.act(self.attention[i](h))
+            if self.attention_dropout is not None:
+                a = F.dropout(a, self.attention_dropout)
+            if self.input_dropout is not None:
+                hvv = F.dropout(hvv, self.input_dropout)
+            h = torch.sum(a * hvv, 0, keepdim=True)
+            msgs_repr.append(h)
+
+        return msgs_repr
+
+
+class NodeUpdateModule(nn.Module):
+    def __init__(self, residual, fc, act, aggregator):
+        super(NodeUpdateModule, self).__init__()
+        
+        self.residual = residual
+        self.fc = fc
+        self.act = act
+        self.aggregator = aggregator
+
+    def forward(self, node, msgs_repr):
+        # apply residual connection and activation for each head
+        for i in range(len(msgs_repr)):
+            if self.residual:
+                h = self.fc[i](node['h'])
+                msgs_repr[i] = msgs_repr[i] + h
+            if self.act is not None:
+                msgs_repr[i] = self.act(msgs_repr[i])
+
+        # aggregate multi-head results
+        h = self.aggregator(msgs_repr)
+        c0 = torch.zeros(h.shape)
+        if node['c'] is None:
+            c0 = torch.zeros(h.shape)
+        else:
+            c0 = node['c']
+        if node['h_i'] is None:
+            h0 = torch.zeros(h.shape)
+        else:
+            h0 = node['h_i']
+        lstm = nn.LSTM(input_size=h.shape[1], hidden_size=h.shape[1], num_layers=1)
+        
+        #add dimension to handle sequential (create sequence of length 1)
+        h, (h_i, c) = lstm(h.unsqueeze(0), (h0.unsqueeze(0), c0.unsqueeze(0)))
+        
+        #remove sequential dim
+        h = torch.squeeze(h, 0)
+        h_i = torch.squeeze(h, 0)
+        c = torch.squeeze(c, 0)
+        
+        return {'h': h, 'c':c, 'h_i':h_i}
+
+class GiniPath(nn.Module):
+    def __init__(self, num_layers, in_dim, num_hidden, num_classes, num_heads,
+            activation, input_dropout, attention_dropout, use_residual=False ):
+        super(GiniPath, self).__init__()
+
+        self.input_dropout = input_dropout
+        self.reduce_layers = nn.ModuleList()
+        self.update_layers = nn.ModuleList()
+        # hidden layers
+        for i in range(num_layers):
+            if i == 0:
+                last_dim = in_dim
+                residual = False
+            else:
+                last_dim = num_hidden * num_heads # because of concat heads
+                residual = use_residual
+            self.reduce_layers.append(
+                    NodeReduceModule(last_dim, num_hidden, num_heads, input_dropout,
+                        attention_dropout))
+            self.update_layers.append(
+                    NodeUpdateModule(residual, self.reduce_layers[-1].fc, activation,
+                        lambda x: torch.cat(x, 1)))
+        # projection
+        self.reduce_layers.append(
+            NodeReduceModule(num_hidden * num_heads, num_classes, 1, input_dropout,
+                attention_dropout))
+        self.update_layers.append(
+            NodeUpdateModule(False, self.reduce_layers[-1].fc, None, sum))
+
+    def forward(self, g):
+        g.register_message_func(lambda src, dst, edge: (src['h'], dst['h']))
+        for reduce_func, update_func in zip(self.reduce_layers, self.update_layers):
+            # apply dropout
+            if self.input_dropout is not None:
+                # TODO (lingfan): use batched dropout once we have better api
+                #                 for global manipulation
+                for n in g.nodes():
+                    g.node[n]['h'] = F.dropout(g.node[n]['h'], p=self.input_dropout)
+                    g.node[n]['c'] = None
+                    g.node[n]['h_i'] = None
+            g.register_reduce_func(reduce_func)
+            g.register_update_func(update_func)
+            g.update_all()
+        logits = [g.node[n]['h'] for n in g.nodes()]
+        logits = torch.cat(logits, dim=0)
+        return logits
+    def train(self, g, features, labels, epochs, loss_f=torch.nn.NLLLoss, loss_params={}, optimizer=torch.optim.Adam, optimizer_parameters=None, lr=0.001, ignore=[0], quiet=False):
+        
+        labels = torch.LongTensor(labels)
+        print(labels)
+        _, labels = torch.max(labels, dim=1)
+        # convert labels and masks to tensor
+        
+        if optimizer_parameters is None:
+            optimizer_parameters = self.parameters()
+        optimizer_f = optimizer(optimizer_parameters, lr)        
+        
+        for epoch in range(args.epochs):
+            # reset grad
+            optimizer_f.zero_grad()
+    
+            # reset graph states
+            for n in g.nodes():
+                g.node[n]['h'] = torch.FloatTensor(features[n].toarray())
+    
+            # forward
+            logits = self.forward(g)
+            
+            loss = loss_f(**loss_params)
+            idx = [i for i, a in enumerate(labels) if a not in ignore]
+            logits = logits[idx, :]
+            labels = labels[idx]
+            out = loss(logits, labels)
+            
+            if not quiet:
+                print("epoch {} loss: {}".format(epoch, out))
+                
+            out.backward()
+            optimizer_f.step()
+
+def main(args):
+    # dropout parameters
+    input_dropout = 0.2
+    attention_dropout = 0.2
+
+    # load and preprocess dataset
+    adj, features, y_train, y_val, y_test, train_mask, val_mask, test_mask = load_data(args.dataset)
+    features = preprocess_features(features)
+
+    # initialize graph
+    g = DGLGraph(adj)
+
+    # create model
+    model = GiniPath(args.num_layers,
+                features.shape[1],
+                args.num_hidden,
+                y_train.shape[1],
+                args.num_heads,
+                F.elu,
+                input_dropout,
+                attention_dropout,
+                args.residual)
+    model.train(g, features, y_train, epochs=10)
+
+if __name__ == '__main__':
+    parser = argparse.ArgumentParser(description='GAT')
+    parser.add_argument("--dataset", type=str, required=True,
+            help="dataset name")
+    parser.add_argument("--epochs", type=int, default=10,
+            help="training epoch")
+    parser.add_argument("--num-heads", type=int, default=3,
+            help="number of attentional heads to use")
+    parser.add_argument("--num-layers", type=int, default=1,
+            help="number of hidden layers")
+    parser.add_argument("--num-hidden", type=int, default=8,
+            help="size of hidden units")
+    parser.add_argument("--residual", action="store_true",
+            help="use residual connection")
+    parser.add_argument("--lr", type=float, default=0.001,
+            help="learning rate")
+    args = parser.parse_args()
+    print(args)
+
+    main(args)
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