問題文
問題の概要
CNN を実装します。なお実装時には『現場で使える！PyTorch開発入門 深層学習モデルの作成とアプリケーションへの実装』（翔泳社）のサンプルコードを一部流用しました。
# ref: https://www.shoeisha.co.jp/book/detail/9784798157184 import re from collections import defaultdict import joblib import pandas as pd import torch from gensim.models import KeyedVectors from torch import nn, optim from torch.utils.data import DataLoader, Dataset from tqdm import tqdm def cleanText(text): remove_marks_regex = re.compile("[,\.\(\)\[\]\*:;]|<.*?>") shift_marks_regex = re.compile("([?!])") # !?以外の記号の削除 text = remove_marks_regex.sub("", text) # !?と単語の間にスペースを挿入 text = shift_marks_regex.sub(r" \1 ", text) return text def list2tensor(token_idxes, max_len=20, padding=True): if len(token_idxes) > max_len: token_idxes = token_idxes[:max_len] n_tokens = len(token_idxes) if padding: token_idxes = token_idxes + [0] * (max_len - len(token_idxes)) return torch.tensor(token_idxes, dtype=torch.int64), n_tokens class CNN(nn.Module): def __init__(self, num_embeddings, embedding_dim=300, hidden_size=300, output_size=1, kernel_size=3): super().__init__() # self.emb = nn.Embedding(num_embeddings, embedding_dim, # padding_idx=0) model = KeyedVectors.load_word2vec_format('ch07/GoogleNews-vectors-negative300.bin', binary=True) weights = torch.FloatTensor(model.vectors) self.emb = nn.Embedding.from_pretrained(weights) self.content_conv = nn.Sequential( nn.Conv1d(in_channels=embedding_dim, out_channels=hidden_size, kernel_size=kernel_size), nn.ReLU(), nn.MaxPool1d(kernel_size=(20 - kernel_size + 1)) ) self.linear = nn.Linear(hidden_size, output_size) def forward(self, x): x = self.emb(x) content_out = self.content_conv(x.permute(0, 2, 1)) reshaped = content_out.view(content_out.size(0), -1) x = self.linear(reshaped) return x class TITLEDataset(Dataset): def __init__(self, section='train'): X_train = pd.read_table(f'ch06/{section}.txt', header=None) use_cols = ['TITLE', 'CATEGORY'] X_train.columns = use_cols d = defaultdict(int) for text in X_train['TITLE']: text = cleanText(text) for word in text.split(): d[word] += 1 dc = sorted(d.items(), key=lambda x: x[1], reverse=True) words = [] idx = [] for i, a in enumerate(dc, 1): words.append(a[0]) if a[1] < 2: idx.append(0) else: idx.append(i) self.word2token = dict(zip(words, idx)) self.data = (X_train['TITLE'].apply(lambda x: list2tensor( [self.word2token[word] if word in self.word2token.keys() else 0 for word in cleanText(x).split()]))) y_train = pd.read_table(f'ch06/{section}.txt', header=None)[1].values self.labels = y_train @property def vocab_size(self): return len(self.word2token) def __len__(self): return len(self.labels) def __getitem__(self, idx): data, n_tokens = self.data[idx] label = self.labels[idx] return data, label, n_tokens if __name__ == "__main__": device = torch.device('cuda:0' if torch.cuda.is_available() else 'cpu') batch_size = 640 train_data = TITLEDataset(section='train') train_loader = DataLoader(train_data, batch_size=batch_size, shuffle=True, num_workers=4) net = CNN(train_data.vocab_size + 1, output_size=4) net = net.to(device) for epoch in tqdm(range(10)): net.train() for x, y, nt in train_loader: x = x.to(device) y = y.to(device) nt = nt.to(device) y_pred = net(x)
