ANLP_WS24_CA2/bert_no_ernie.py

172 lines
6.5 KiB
Python

# PyTorch Imports
import torch
import torch.nn as nn
import torch.optim as optim
from torch.utils.data import Dataset, DataLoader
# scikit-learn Imports
# from sklearn.metrics import accuracy_score, confusion_matrix
from sklearn.model_selection import train_test_split
# Bert imports
from transformers import BertForSequenceClassification, AutoTokenizer
#Default imports (pandas, numpy, matplotlib, etc.)
import pandas as pd
import numpy as np
import matplotlib.pyplot as plt
## Select Device
if torch.cuda.is_available():
DEVICE = torch.device("cuda")
else:
DEVICE = torch.device("cpu")
class SimpleHumorDataset(Dataset):
def __init__(self,tokenizer:AutoTokenizer,dataframe:pd.DataFrame,max_length:int=128):
super(SimpleHumorDataset,self).__init__()
self.tokenizer = tokenizer
self.max_length = max_length
self.text = dataframe['text'].to_list()
self.labels = dataframe['is_humor'].to_list()
def __getitem__(self,idx:int):
text = self.text[idx]
labels = self.labels[idx]
encoding = self.tokenizer(
text,
padding="max_length",
return_attention_mask = True,
max_length=self.max_length,
truncation = True,
return_tensors = 'pt'
)
input_ids = encoding['input_ids'].flatten()
attention_mask = encoding['attention_mask'].flatten()
return {
'input_ids': torch.as_tensor(input_ids,dtype=torch.long),
'attention_mask':torch.as_tensor(attention_mask,dtype=torch.long),
'labels':torch.tensor(labels,dtype=torch.long)
}
def __len__(self):
return len(self.labels)
class CustomBert(nn.Module):
def __init__(self):
super().__init__()
#Bert + Custom Layers (Not a tuple any longer -- idk why)
self.bfsc = BertForSequenceClassification.from_pretrained("bert-base-uncased")
self.classifier = nn.Linear(2,2)
self.sm = nn.Softmax(dim=1)
def forward(self, input_ids, attention_mask):
seq_out = self.bfsc(input_ids, attention_mask = attention_mask)
x = self.classifier(seq_out.logits)
return self.sm(x)
def training_loop(model:CustomBert,criterion:nn.CrossEntropyLoss,optimizer:optim.AdamW,train_loader:DataLoader):
model.train()
total_loss = 0
for train_batch in train_loader:
# Set Gradient to Zero
optimizer.zero_grad()
# Unpack batch values and "push" it to GPU
input_ids, att_mask, labels = train_batch.values()
input_ids, att_mask, labels = input_ids.to(DEVICE),att_mask.to(DEVICE),labels.to(DEVICE)
# Feed Model with Data
outputs = model(input_ids, attention_mask=att_mask)
loss = criterion(outputs,labels)
loss.backward()
optimizer.step()
total_loss+=loss.item()
print(f"Total Loss is {(total_loss/len(train_loader)):.4f}")
return (total_loss/len(train_loader))
def eval_loop(model:CustomBert,criterion:nn.CrossEntropyLoss,validation_loader:DataLoader):
model.eval()
total, correct = 0.0, 0.0
total_loss = 0.0
with torch.no_grad():
for val_batch in validation_loader:
input_ids, att_mask ,labels = val_batch.values()
input_ids, att_mask, labels = input_ids.to(DEVICE),att_mask.to(DEVICE), labels.to(DEVICE)
outputs = model(input_ids,attention_mask=att_mask)
loss = criterion(outputs,labels)
total_loss += loss.item()
predictions = torch.argmax(outputs,1)
total += labels.size(0)
correct += (predictions == labels).sum().item()
print(f"Total Loss: {total_loss/len(validation_loader)} ### Test Accuracy {correct/total*100}%")
return total_loss/len(validation_loader)
if __name__ == "__main__":
torch.manual_seed(501)
# HYPERPARAMETERS
# Set Max Epoch Amount
EPOCH = 1
# DROPOUT-PROBABILITY
DROPOUT = 0.1
# BATCHSIZE
BATCH_SIZE = 8
#LEARNING RATE
LEARNING_RATE = 1e-5
# Initialize Bert Model with dropout probability and Num End Layers
mybert = CustomBert()
print("Bert Initialized")
mybert.to(DEVICE)
# Read Raw Data from csv and save as DataFrame
df = pd.read_csv("./data/hack.csv",encoding="latin1")
print("Raw Data read")
# Initialize BertTokenizer from Pretrained
tokenizer = AutoTokenizer.from_pretrained("google-bert/bert-base-uncased",do_lower_case=True)
print("Tokenizer Initialized")
# print(tokenizer(df['text'][0],padding=True,truncation=True,max_length=256))
#Split DataFrame into Train and Test Sets
train,test = train_test_split(df,random_state=501,test_size=.2)
print("Splitted Data in Train and Test Sets")
# val = []
# Create Custom Datasets for Train and Test
train_data = SimpleHumorDataset(tokenizer,train)
# val_data = SimpleHumorDataset(tokenizer,val)
test_data = SimpleHumorDataset(tokenizer,test)
print("Custom Datasets created")
# Initialize Dataloader with Train and Test Sets
train_loader = DataLoader(dataset=train_data,batch_size=BATCH_SIZE,shuffle=True)
# val_loader = DataLoader(dataset=val_data,batch_size=BATCH_SIZE,shuffle=True)
test_loader = DataLoader(dataset=test_data,batch_size=BATCH_SIZE,shuffle=False)
print("DataLoaders created")
# Set criterion to Cross Entropy and define Adam Optimizer with model parameters and learning rate
criterion_cross_entropy = nn.CrossEntropyLoss()
optimizer_adamW = optim.Adam(mybert.parameters(), lr = LEARNING_RATE)
import time
# Set Scheduler for dynamically Learning Rate adjustment
loss_values = np.zeros(EPOCH)
eval_values = np.zeros(EPOCH)
start = time.time()
for epoch in range(EPOCH):
print(f"For {epoch+1} the Scores are: ")
loss_values[epoch] = training_loop(mybert,optimizer=optimizer_adamW,criterion=criterion_cross_entropy,train_loader=train_loader)
eval_values[epoch] = eval_loop(mybert,criterion=criterion_cross_entropy,validation_loader=test_loader)
end = time.time()
print((end-start),"seconds per epoch needed")
# Visualize Training Loss
plt.plot(loss_values)
plt.plot(eval_values)
plt.hlines(np.mean(loss_values),xmin=0,xmax=EPOCH,colors='red',linestyles="dotted",label="Average Loss")
plt.hlines(np.mean(eval_values),xmin=0,xmax=EPOCH,colors='green',linestyles="dashed",label="Average Val Loss")
plt.title("Test Loss")
plt.xlabel("Num Epochs")
plt.ylabel("Total Loss of Epoch")
plt.show()