update textgen lstm

This commit is contained in:
2022-11-13 14:26:21 +01:00
parent 7fc87def1e
commit d5f1fbfbc4

View File

@ -2,6 +2,7 @@
import re, random
import numpy as np
import matplotlib.pyplot as plt
import torch
import torch.nn.functional as F
from textgen import textgen
@ -16,9 +17,11 @@ install()
class Model(nn.ModuleList):
def __init__(self, args):
def __init__(self, args, device):
super(Model, self).__init__()
self.device = device
self.batch_size = args["batch_size"]
self.hidden_dim = args["hidden_dim"]
self.input_size = args["vocab_size"]
@ -26,7 +29,7 @@ class Model(nn.ModuleList):
self.sequence_len = args["window"]
# Dropout
self.dropout = nn.Dropout(0.25)
self.dropout = nn.Dropout(0.25) # Don't need to set device for the layers as we transfer the whole model later
# Embedding layer
self.embedding = nn.Embedding(self.input_size, self.hidden_dim, padding_idx=0)
@ -47,16 +50,16 @@ class Model(nn.ModuleList):
# Bi-LSTM
# hs = [batch_size x hidden_size]
# cs = [batch_size x hidden_size]
hs_forward = torch.zeros(x.size(0), self.hidden_dim)
cs_forward = torch.zeros(x.size(0), self.hidden_dim)
hs_backward = torch.zeros(x.size(0), self.hidden_dim)
cs_backward = torch.zeros(x.size(0), self.hidden_dim)
hs_forward = torch.zeros(x.size(0), self.hidden_dim).to(self.device) # Need to specify device here as this is not part of the model directly
cs_forward = torch.zeros(x.size(0), self.hidden_dim).to(self.device)
hs_backward = torch.zeros(x.size(0), self.hidden_dim).to(self.device)
cs_backward = torch.zeros(x.size(0), self.hidden_dim).to(self.device)
# LSTM
# hs = [batch_size x (hidden_size * 2)]
# cs = [batch_size x (hidden_size * 2)]
hs_lstm = torch.zeros(x.size(0), self.hidden_dim * 2)
cs_lstm = torch.zeros(x.size(0), self.hidden_dim * 2)
hs_lstm = torch.zeros(x.size(0), self.hidden_dim * 2).to(self.device)
cs_lstm = torch.zeros(x.size(0), self.hidden_dim * 2).to(self.device)
# Weights initialization
torch.nn.init.kaiming_normal_(hs_forward)
@ -104,16 +107,43 @@ class LSTMTextGenerator(textgen):
self.windowsize = windowsize # We slide a window over the character sequence and look at the next letter,
# similar to the Markov chain order
def init(self, filename):
self.filename = filename
# Use this to generate one hot vector and filter characters
self.letters = ["a", "b", "c", "d", "e", "f", "g", "h", "i", "j", "k", "l", "m",
"n", "o", "p", "q", "r", "s", "t", "u", "v", "w", "x", "y", "z", " "]
"n", "o", "p", "q", "r", "s", "t", "u", "v", "w", "x", "y", "z", "ä", "ö", "ü", ".", " "]
with open(f"./textfiles/{filename}.txt", "r") as file:
lines = [line.lower() for line in file.readlines()] # lowercase list
text = " ".join(lines) # single string
self.charbase = [char for char in text if char in self.letters] # list of characters
# Select device
if torch.cuda.is_available():
dev = "cuda:0"
print("Selected GPU for LSTM")
else:
dev = "cpu"
print("Selected CPU for LSTM")
self.device = torch.device(dev)
# Init model
self.args = {
"window": self.windowsize,
"hidden_dim": 128,
"vocab_size": len(self.letters),
"batch_size": 128,
"learning_rate": 0.0005,
"num_epochs": 100
}
self.model = Model(self.args, self.device)
self.model.to(self.device) # All model layers need to use the correct tensors (cpu/gpu)
# Needed for both training and generation
self.__generate_char_sequences()
# Helper shit
def __char_to_idx(self, char):
@ -148,72 +178,50 @@ class LSTMTextGenerator(textgen):
# Interface shit
# TODO: Also save/load generated prefixes
def load(self):
print(f"Loaded LSTM model with {len(self.charbase)} characters from file.")
print(f"Loading \"{self.filename}\" LSTM model with {len(self.charbase)} characters from file.")
# TODO: Deduplicate args
args = {
"window": self.windowsize,
"hidden_dim": 128,
"vocab_size": len(self.letters),
"batch_size": 128,
"learning_rate": 0.001,
"num_epochs": 50
}
self.model = Model(args)
# model.load_state_dict(torch.load('weights/kommunistisches_manifest_lstm_model.pt'))
self.model.load_state_dict(torch.load(f"weights/{self.filename}_lstm_model.pt"))
def train(self):
print(f"Training LSTM model with {len(self.charbase)} characters.")
print(f"Training \"{self.filename}\" LSTM model with {len(self.charbase)} characters.")
args = {
"window": self.windowsize,
"hidden_dim": 128,
"vocab_size": len(self.letters),
"batch_size": 128,
"learning_rate": 0.001,
"num_epochs": 50
}
self.__generate_char_sequences()
# Model initialization
self.model = Model(args)
# Optimizer initialization
optimizer = optim.RMSprop(self.model.parameters(), lr=args["learning_rate"])
# Optimizer initialization, RMSprop for RNN
optimizer = optim.RMSprop(self.model.parameters(), lr=self.args["learning_rate"])
# Defining number of batches
num_batches = int(len(self.prefixes) / args["batch_size"])
num_batches = int(len(self.prefixes) / self.args["batch_size"])
# Set model in training mode
self.model.train()
losses = []
# Training pahse
for epoch in range(args["num_epochs"]):
for epoch in range(self.args["num_epochs"]):
# Mini batches
for i in range(num_batches):
# Batch definition
try:
x_batch = self.prefixes[i * args["batch_size"] : (i + 1) * args["batch_size"]]
y_batch = self.suffixes[i * args["batch_size"] : (i + 1) * args["batch_size"]]
x_batch = self.prefixes[i * self.args["batch_size"]:(i + 1) * self.args["batch_size"]]
y_batch = self.suffixes[i * self.args["batch_size"]:(i + 1) * self.args["batch_size"]]
except:
x_batch = self.prefixes[i * args["batch_size"] :]
y_batch = self.suffixes[i * args["batch_size"] :]
x_batch = self.prefixes[i * self.args["batch_size"]:]
y_batch = self.suffixes[i * self.args["batch_size"]:]
# Convert numpy array into torch tensors
x = torch.from_numpy(x_batch).type(torch.long)
y = torch.from_numpy(y_batch).type(torch.long)
x = torch.from_numpy(x_batch).type(torch.long).to(self.device)
y = torch.from_numpy(y_batch).type(torch.long).to(self.device)
# Feed the model
y_pred = self.model(x)
# Loss calculation
loss = F.cross_entropy(y_pred, y.squeeze())
loss = F.cross_entropy(y_pred, y.squeeze()).to(self.device)
losses += [loss.item()]
# Clean gradients
optimizer.zero_grad()
@ -226,35 +234,44 @@ class LSTMTextGenerator(textgen):
print("Epoch: %d , loss: %.5f " % (epoch, loss.item()))
torch.save(self.model.state_dict(), 'weights/kommunistisches_manifest_lstm_model.pt')
torch.save(self.model.state_dict(), f"weights/{self.filename}_lstm_model.pt")
print(f"Saved \"{self.filename}\" LSTM model to file")
plt.plot(np.arange(0, len(losses)), losses)
plt.title(self.filename)
plt.show()
def generate_sentence(self):
# Randomly is selected the index from the set of sequences
start = np.random.randint(0, len(self.prefixes)-1)
# Convert back to string to match complete_sentence
pattern = "".join([self.__idx_to_char(char) for char in self.prefixes[start]]) # random sequence from the training text
return self.complete_sentence(pattern)
def complete_sentence(self, prefix):
print("Prefix:", prefix)
# Convert to indexes np.array
pattern = np.array([self.__char_to_idx(char) for char in prefix])
# Set the model in evalulation mode
self.model.eval()
# Define the softmax function
softmax = nn.Softmax(dim=1)
# Randomly is selected the index from the set of sequences
start = np.random.randint(0, len(self.prefixes)-1)
# The pattern is defined given the random idx
pattern = self.prefixes[start]
# By making use of the dictionaries, it is printed the pattern
print("\nPattern: \n")
print(''.join([self.__idx_to_char(value) for value in pattern]), "\"")
softmax = nn.Softmax(dim=1).to(self.device)
# In full_prediction we will save the complete prediction
full_prediction = pattern.copy()
# the prediction starts, it is going to be predicted a given
# number of characters
for _ in range(250):
print("Generating sentence...")
# Predic the next characters one by one, append chars to the starting pattern until . is reached, max 500 iterations
for _ in range(500):
# the numpy patterns is transformed into a tesor-type and reshaped
pattern = torch.from_numpy(pattern).type(torch.long)
pattern = torch.from_numpy(pattern).type(torch.long).to(self.device)
pattern = pattern.view(1,-1)
# make a prediction given the pattern
@ -263,12 +280,12 @@ class LSTMTextGenerator(textgen):
prediction = softmax(prediction)
# the prediction tensor is transformed into a numpy array
prediction = prediction.squeeze().detach().numpy()
prediction = prediction.squeeze().detach().cpu().numpy()
# it is taken the idx with the highest probability
arg_max = np.argmax(prediction)
# the current pattern tensor is transformed into numpy array
pattern = pattern.squeeze().detach().numpy()
pattern = pattern.squeeze().detach().cpu().numpy()
# the window is sliced 1 character to the right
pattern = pattern[1:]
# the new pattern is composed by the "old" pattern + the predicted character
@ -277,8 +294,10 @@ class LSTMTextGenerator(textgen):
# the full prediction is saved
full_prediction = np.append(full_prediction, arg_max)
print("prediction: \n")
print(''.join([self.__idx_to_char(value) for value in full_prediction]), "\"")
# Stop on . character
if self.__idx_to_char(arg_max) == ".":
break
def complete_sentence(self, prefix):
pass
full_prediction = "".join([self.__idx_to_char(value) for value in full_prediction])
print("Generated:", full_prediction)
return full_prediction