gFun/refactor/models/lstm_class.py

115 lines
4.9 KiB
Python
Executable File

#taken from https://github.com/prakashpandey9/Text-Classification-Pytorch/blob/master/models/LSTM.py
import torch
import torch.nn as nn
from torch.autograd import Variable
from models.helpers import *
class RNNMultilingualClassifier(nn.Module):
def __init__(self, output_size, hidden_size, lvocab_size, learnable_length, lpretrained=None,
drop_embedding_range=None, drop_embedding_prop=0, post_probabilities=True, only_post=False,
bert_embeddings=False):
super(RNNMultilingualClassifier, self).__init__()
self.output_size = output_size
self.hidden_size = hidden_size
self.drop_embedding_range = drop_embedding_range
self.drop_embedding_prop = drop_embedding_prop
self.post_probabilities = post_probabilities
self.bert_embeddings = bert_embeddings
assert 0 <= drop_embedding_prop <= 1, 'drop_embedding_prop: wrong range'
self.lpretrained_embeddings = nn.ModuleDict()
self.llearnable_embeddings = nn.ModuleDict()
self.embedding_length = None
self.langs = sorted(lvocab_size.keys())
self.only_post = only_post
self.n_layers = 1
self.n_directions = 1
self.dropout = nn.Dropout(0.6)
lstm_out = 256
ff1 = 512
ff2 = 256
lpretrained_embeddings = {}
llearnable_embeddings = {}
if only_post==False:
for l in self.langs:
pretrained = lpretrained[l] if lpretrained else None
pretrained_embeddings, learnable_embeddings, embedding_length = init_embeddings(
pretrained, lvocab_size[l], learnable_length
)
lpretrained_embeddings[l] = pretrained_embeddings
llearnable_embeddings[l] = learnable_embeddings
self.embedding_length = embedding_length
# self.lstm = nn.LSTM(self.embedding_length, hidden_size, dropout=0.2 if self.n_layers>1 else 0, num_layers=self.n_layers, bidirectional=(self.n_directions==2))
self.rnn = nn.GRU(self.embedding_length, hidden_size)
self.linear0 = nn.Linear(hidden_size * self.n_directions, lstm_out)
self.lpretrained_embeddings.update(lpretrained_embeddings)
self.llearnable_embeddings.update(llearnable_embeddings)
self.linear1 = nn.Linear(lstm_out, ff1)
self.linear2 = nn.Linear(ff1, ff2)
if only_post:
self.label = nn.Linear(output_size, output_size)
elif post_probabilities and not bert_embeddings:
self.label = nn.Linear(ff2 + output_size, output_size)
elif bert_embeddings and not post_probabilities:
self.label = nn.Linear(ff2 + 768, output_size)
elif post_probabilities and bert_embeddings:
self.label = nn.Linear(ff2 + output_size + 768, output_size)
else:
self.label = nn.Linear(ff2, output_size)
def forward(self, input, post, bert_embed, lang):
if self.only_post:
doc_embedding = post
else:
doc_embedding = self.transform(input, lang)
if self.post_probabilities:
doc_embedding = torch.cat([doc_embedding, post], dim=1)
if self.bert_embeddings:
doc_embedding = torch.cat([doc_embedding, bert_embed], dim=1)
logits = self.label(doc_embedding)
return logits
def transform(self, input, lang):
batch_size = input.shape[0]
input = embed(self, input, lang)
input = embedding_dropout(input, drop_range=self.drop_embedding_range, p_drop=self.drop_embedding_prop,
training=self.training)
input = input.permute(1, 0, 2)
h_0 = Variable(torch.zeros(self.n_layers*self.n_directions, batch_size, self.hidden_size).cuda())
# c_0 = Variable(torch.zeros(self.n_layers*self.n_directions, batch_size, self.hidden_size).cuda())
# output, (_, _) = self.lstm(input, (h_0, c_0))
output, _ = self.rnn(input, h_0)
output = output[-1, :, :]
output = F.relu(self.linear0(output))
output = self.dropout(F.relu(self.linear1(output)))
output = self.dropout(F.relu(self.linear2(output)))
return output
def finetune_pretrained(self):
for l in self.langs:
self.lpretrained_embeddings[l].requires_grad = True
self.lpretrained_embeddings[l].weight.requires_grad = True
def get_embeddings(self, input, lang):
batch_size = input.shape[0]
input = embed(self, input, lang)
input = embedding_dropout(input, drop_range=self.drop_embedding_range, p_drop=self.drop_embedding_prop,
training=self.training)
input = input.permute(1, 0, 2)
h_0 = Variable(torch.zeros(self.n_layers * self.n_directions, batch_size, self.hidden_size).cuda())
output, _ = self.rnn(input, h_0)
output = output[-1, :, :]
return output.cpu().detach().numpy()