File size: 4,794 Bytes
c617d00
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
import os
import time
import torch
import torch.nn as nn
import torch.optim as optim
from torch.utils.data import DataLoader, random_split
import sys

project_root = os.path.abspath(os.path.join(os.path.dirname(__file__), ".."))
sys.path.insert(0, project_root)

from arthaml.data.vocabulary import Vocabulary
from arthaml.data.dataset import TranslationDataset
from arthaml.models.encoder import Encoder
from arthaml.models.decoder import Attention, Decoder
from arthaml.models.seq2seq import Seq2Seq
from arthaml.evaluation.bleu import compute_bleu

def train(model, iterator, optimizer, criterion, clip, device):
    model.train()
    epoch_loss = 0
    
    for i, batch in enumerate(iterator):
        src = batch['src'].to(device)
        tgt = batch['tgt'].to(device)
        src_len = batch['src_len'].to(device)
        
        optimizer.zero_grad()
        
        output = model(src, src_len, tgt, teacher_forcing_ratio=0.5)
        
        output_dim = output.shape[-1]
        
        # Ignored t=0 since it's the <SOS> token
        output = output[:, 1:].reshape(-1, output_dim)
        tgt = tgt[:, 1:].reshape(-1)
        
        loss = criterion(output, tgt)
        loss.backward()
        
        torch.nn.utils.clip_grad_norm_(model.parameters(), clip)
        optimizer.step()
        
        epoch_loss += loss.item()
        
    return epoch_loss / len(iterator)

def evaluate(model, iterator, criterion, device):
    model.eval()
    epoch_loss = 0
    
    with torch.no_grad():
        for i, batch in enumerate(iterator):
            src = batch['src'].to(device)
            tgt = batch['tgt'].to(device)
            src_len = batch['src_len'].to(device)
            
            output = model(src, src_len, tgt, teacher_forcing_ratio=0)
            
            output_dim = output.shape[-1]
            
            output = output[:, 1:].reshape(-1, output_dim)
            tgt = tgt[:, 1:].reshape(-1)
            
            loss = criterion(output, tgt)
            epoch_loss += loss.item()
            
    return epoch_loss / len(iterator)

def main():
    device = torch.device('cuda' if torch.cuda.is_available() else 'cpu')
    print(f"Using device: {device}")
    
    os.makedirs(os.path.join(project_root, 'models'), exist_ok=True)
    
    print("Loading vocabularies...")
    vocab_en = Vocabulary("English")
    vocab_en.load(os.path.join(project_root, 'data/processed/vocab_en.json'))
    vocab_kn = Vocabulary("Kannada")
    vocab_kn.load(os.path.join(project_root, 'data/processed/vocab_kn.json'))
    
    print("Loading dataset...")
    data_path = os.path.join(project_root, 'data/processed/clean_50k.json')
    dataset = TranslationDataset(data_path, vocab_en, vocab_kn, max_len=50)
    
    val_size = int(0.1 * len(dataset))
    train_size = len(dataset) - val_size
    train_dataset, val_dataset = random_split(dataset, [train_size, val_size])
    
    train_iterator = DataLoader(train_dataset, batch_size=32, shuffle=True)
    val_iterator = DataLoader(val_dataset, batch_size=32, shuffle=False)
    
    print("Initializing models...")
    encoder = Encoder(vocab_size=21551, embed_dim=256, hidden_size=512, num_layers=2, dropout_p=0.3, padding_idx=0)
    attention = Attention(hidden_size=512)
    decoder = Decoder(attention, vocab_size=26802, embed_dim=256, hidden_size=512, num_layers=2, dropout_p=0.3, padding_idx=0)
    
    model = Seq2Seq(encoder, decoder, device).to(device)
    
    optimizer = optim.Adam(model.parameters(), lr=0.001)
    criterion = nn.CrossEntropyLoss(ignore_index=0)
    
    N_EPOCHS = 10
    CLIP = 1.0
    
    best_val_loss = float('inf')
    best_bleu = 0.0
    
    print("Starting training...")
    for epoch in range(N_EPOCHS):
        start_time = time.time()
        
        train_loss = train(model, train_iterator, optimizer, criterion, CLIP, device)
        val_loss = evaluate(model, val_iterator, criterion, device)
        
        bleu_score = compute_bleu(model, val_dataset, vocab_kn, device, n=500)
        
        end_time = time.time()
        time_taken = int(end_time - start_time)
        
        if val_loss < best_val_loss:
            best_val_loss = val_loss
            torch.save(model.state_dict(), os.path.join(project_root, 'models/best_model.pth'))
            
        if bleu_score > best_bleu:
            best_bleu = bleu_score
            
        print(f"Epoch {epoch+1:02} | Train Loss: {train_loss:.3f} | Val Loss: {val_loss:.3f} | BLEU: {bleu_score:.2f} | Time: {time_taken}s")
        
    torch.save(model.state_dict(), os.path.join(project_root, 'models/final_model.pth'))
    print(f"\nTraining Complete!")
    print(f"Best Val Loss: {best_val_loss:.3f}")
    print(f"Best BLEU Score: {best_bleu:.2f}")

if __name__ == "__main__":
    main()