RAGtutorial.py

# -*- coding: utf-8 -*-
"""
Spyder Editor

This is a temporary script file.
"""
from lxml import html
from lxml.html.clean import clean_html

dataset = []
with open(r'C:\git\eviewshelp\chm\test\cprogram-EViews_Programming.html', 'r') as file:
  dataset= file.read()
  
#%%  
parsed_html = html.fromstring(dataset)

# Clean the HTML
cleaned_html = clean_html(parsed_html)

# Extract text content
dataset = cleaned_html.text_content().strip()
#dataset = clean_html(dataset).text_content().strip()
print(f'Loaded {len(dataset)} entries')

#%%Begin program
import ollama

EMBEDDING_MODEL = 'hf.co/CompendiumLabs/bge-base-en-v1.5-gguf'
LANGUAGE_MODEL = 'hf.co/bartowski/Llama-3.2-1B-Instruct-GGUF'

# Each element in the VECTOR_DB will be a tuple (chunk, embedding)
# The embedding is a list of floats, for example: [0.1, 0.04, -0.34, 0.21, ...]
VECTOR_DB = []
#%% routines
def add_chunk_to_database(chunk):
  embedding = ollama.embed(model=EMBEDDING_MODEL, input=chunk)['embeddings'][0]
  VECTOR_DB.append((chunk, embedding))
  
def cosine_similarity(a, b):
  dot_product = sum([x * y for x, y in zip(a, b)])
  norm_a = sum([x ** 2 for x in a]) ** 0.5
  norm_b = sum([x ** 2 for x in b]) ** 0.5
  return dot_product / (norm_a * norm_b)

def retrieve(query, top_n=3):
  query_embedding = ollama.embed(model=EMBEDDING_MODEL, input=query)['embeddings'][0]
  # temporary list to store (chunk, similarity) pairs
  similarities = []
  for chunk, embedding in VECTOR_DB:
    similarity = cosine_similarity(query_embedding, embedding)
    similarities.append((chunk, similarity))
  # sort by similarity in descending order, because higher similarity means more relevant chunks
  similarities.sort(key=lambda x: x[1], reverse=True)
  # finally, return the top N most relevant chunks
  return similarities[:top_n]
#%% process data
for i, chunk in enumerate(dataset):
  add_chunk_to_database(chunk)
  print(f'Added chunk {i+1}/{len(dataset)} to the database')
  
  
 #%% Do the magic
  
input_query = input('Ask me a question: ')
retrieved_knowledge = retrieve(input_query)

print('Retrieved knowledge:')
for chunk, similarity in retrieved_knowledge:
  print(f' - (similarity: {similarity:.2f}) {chunk}')

instruction_prompt = f'''You are a helpful chatbot.
Use only the following pieces of context to answer the question. Don't make up any new information:
{'\n'.join([f' - {chunk}' for chunk, similarity in retrieved_knowledge])}
'''

stream = ollama.chat(
  model=LANGUAGE_MODEL,
  messages=[
    {'role': 'system', 'content': instruction_prompt},
    {'role': 'user', 'content': input_query},
  ],
  stream=True,
)

# print the response from the chatbot in real-time
print('Chatbot response:')
for chunk in stream:
  print(chunk['message']['content'], end='', flush=True)