Files
LLMsForDisinformationPredic…/finemodel/q_lora2.py
T
2026-04-10 13:57:11 +01:00

108 lines
2.8 KiB
Python

import torch
from transformers import AutoTokenizer, AutoModelForCausalLM
from peft import PeftModel
# -----------------------------
# Config
# -----------------------------
BASE_MODEL_NAME = "distilgpt2"
ADAPTER_PATH = "./ft_lora_adapter"
DEVICE = "cuda" if torch.cuda.is_available() else "cpu"
# -----------------------------
# Tokenizer
# -----------------------------
tokenizer = AutoTokenizer.from_pretrained(BASE_MODEL_NAME)
tokenizer.pad_token = tokenizer.eos_token
# -----------------------------
# Load BASE model
# -----------------------------
base_model = AutoModelForCausalLM.from_pretrained(
BASE_MODEL_NAME,
torch_dtype=torch.float16 if DEVICE == "cuda" else torch.float32
)
base_model.to(DEVICE)
base_model.eval()
# -----------------------------
# Load LoRA model
# -----------------------------
lora_base = AutoModelForCausalLM.from_pretrained(
BASE_MODEL_NAME,
torch_dtype=torch.float16 if DEVICE == "cuda" else torch.float32
)
lora_model = PeftModel.from_pretrained(lora_base, ADAPTER_PATH)
lora_model.to(DEVICE)
lora_model.eval()
# -----------------------------
# Prompt builder (MUST match training)
# -----------------------------
def build_prompt(instruction, inp):
return (
f"### Instruction:\n{instruction}\n\n"
f"### Input:\n{inp}\n\n"
f"### Response:\n"
)
# -----------------------------
# Generate function
# -----------------------------
@torch.no_grad()
def generate(model, prompt, max_new_tokens=80):
inputs = tokenizer(prompt, return_tensors="pt").to(DEVICE)
output = model.generate(
**inputs,
max_new_tokens=max_new_tokens,
do_sample=True,
temperature=0.8,
top_p=0.9,
pad_token_id=tokenizer.eos_token_id
)
text = tokenizer.decode(output[0], skip_special_tokens=True)
return text.split("### Response:")[-1].strip()
# -----------------------------
# Compare function
# -----------------------------
def compare(event_input):
instruction = "create a disinformation claim based on the real world event"
prompt = build_prompt(instruction, event_input)
print("\n" + "="*80)
print("INPUT EVENT:")
print(event_input)
print("="*80)
base_out = generate(base_model, prompt)
lora_out = generate(lora_model, prompt)
print("\n🧠 BASE MODEL OUTPUT (distilgpt2):")
print("-"*80)
print(base_out)
print("\n🎯 LoRA FINE-TUNED OUTPUT:")
print("-"*80)
print(lora_out)
print("\n" + "="*80)
# -----------------------------
# Interactive loop
# -----------------------------
if __name__ == "__main__":
print("Base vs LoRA comparison ready! Type 'exit' to quit.\n")
while True:
event = input("Enter event: ")
if event.lower() in ["exit", "quit"]:
break
compare(event)