# coding: UTF-8 import numpy as np import torch import torch.nn as nn import torch.nn.functional as F from sklearn import metrics import time from utils import get_time_dif from tensorboardX import SummaryWriter # 权重初始化,默认xavier def init_network(model, method='xavier', exclude='embedding', seed=123): for name, w in model.named_parameters(): if exclude not in name: if 'weight' in name: if method == 'xavier': nn.init.xavier_normal_(w) elif method == 'kaiming': nn.init.kaiming_normal_(w) else: nn.init.normal_(w) elif 'bias' in name: nn.init.constant_(w, 0) else: pass def train(config, model, train_iter, dev_iter, test_iter): start_time = time.time() model.train() optimizer = torch.optim.Adam(model.parameters(), lr=config.learning_rate) # 学习率指数衰减,每次epoch:学习率 = gamma * 学习率 # scheduler = torch.optim.lr_scheduler.ExponentialLR(optimizer, gamma=0.9) total_batch = 0 # 记录进行到多少batch dev_best_loss = float('inf') last_improve = 0 # 记录上次验证集loss下降的batch数 flag = False # 记录是否很久没有效果提升 writer = SummaryWriter(log_dir=config.log_path + '/' + time.strftime('%m-%d_%H.%M', time.localtime())) for epoch in range(config.num_epochs): print('Epoch [{}/{}]'.format(epoch + 1, config.num_epochs)) # scheduler.step() # 学习率衰减 for i, (trains, labels) in enumerate(train_iter): outputs = model(trains) model.zero_grad() loss = F.cross_entropy(outputs, labels) loss.backward() optimizer.step() if total_batch % 100 == 0: # 每多少轮输出在训练集和验证集上的效果 true = labels.data.cpu() predic = torch.max(outputs.data, 1)[1].cpu() train_acc = metrics.accuracy_score(true, predic) dev_acc, dev_loss = evaluate(config, model, dev_iter) if dev_loss < dev_best_loss: dev_best_loss = dev_loss torch.save(model.state_dict(), config.save_path) improve = '*' last_improve = total_batch else: improve = '' time_dif = get_time_dif(start_time) msg = 'Iter: {0:>6}, Train Loss: {1:>5.2}, Train Acc: {2:>6.2%}, Val Loss: {3:>5.2}, Val Acc: {4:>6.2%}, Time: {5} {6}' print(msg.format(total_batch, loss.item(), train_acc, dev_loss, dev_acc, time_dif, improve)) writer.add_scalar("loss/train", loss.item(), total_batch) writer.add_scalar("loss/dev", dev_loss, total_batch) writer.add_scalar("acc/train", train_acc, total_batch) writer.add_scalar("acc/dev", dev_acc, total_batch) model.train() total_batch += 1 if total_batch - last_improve > config.require_improvement: # 验证集loss超过1000batch没下降,结束训练 print("No optimization for a long time, auto-stopping...") flag = True break if flag: break writer.close() test(config, model, test_iter) def test(config, model, test_iter): # test model.load_state_dict(torch.load(config.save_path)) model.eval() start_time = time.time() test_acc, test_loss, test_report, test_confusion = evaluate(config, model, test_iter, test=True) msg = 'Test Loss: {0:>5.2}, Test Acc: {1:>6.2%}' print(msg.format(test_loss, test_acc)) print("Precision, Recall and F1-Score...") print(test_report) print("Confusion Matrix...") print(test_confusion) time_dif = get_time_dif(start_time) print("Time usage:", time_dif) def evaluate(config, model, data_iter, test=False): model.eval() loss_total = 0 predict_all = np.array([], dtype=int) labels_all = np.array([], dtype=int) with torch.no_grad(): for texts, labels in data_iter: outputs = model(texts) loss = F.cross_entropy(outputs, labels) loss_total += loss labels = labels.data.cpu().numpy() predic = torch.max(outputs.data, 1)[1].cpu().numpy() labels_all = np.append(labels_all, labels) predict_all = np.append(predict_all, predic) acc = metrics.accuracy_score(labels_all, predict_all) if test: report = metrics.classification_report(labels_all, predict_all, target_names=config.class_list, digits=4) confusion = metrics.confusion_matrix(labels_all, predict_all) return acc, loss_total / len(data_iter), report, confusion return acc, loss_total / len(data_iter)