Semi-structured RAG#
Let’s evaluate your architecture on a small semi-structured Q&A dataset. This dataset is composed of QA pairs over pdfs that contain tables.
Pre-requisites#
We will install quite a few prerequisites for this example since we are comparing various techinques and models.
%pip install -U langchain langsmith langchainhub langchain_benchmarks langchain_experimental
%pip install --quiet chromadb openai huggingface pandas "unstructured[all-docs]"
For this code to work, please configure LangSmith environment variables with your credentials.
import os
os.environ["LANGCHAIN_ENDPOINT"] = "https://api.smith.langchain.com"
os.environ["LANGCHAIN_API_KEY"] = "sk-..." # Your API key
# Silence warnings from HuggingFace
os.environ["TOKENIZERS_PARALLELISM"] = "false"
Review Q&A Tasks#
The registry provides configurations to test out common architectures on curated datasets.
from langchain_benchmarks import clone_public_dataset, registry
registry = registry.filter(Type="RetrievalTask")
registry
| Name | Type | Dataset ID | Description |
|---|---|---|---|
| LangChain Docs Q&A | RetrievalTask | 452ccafc-18e1-4314-885b-edd735f17b9d | Questions and answers based on a snapshot of the LangChain python docs. The environment provides the documents and the retriever information. Each example is composed of a question and reference answer. Success is measured based on the accuracy of the answer relative to the reference answer. We also measure the faithfulness of the model's response relative to the retrieved documents (if any). |
| Semi-structured Reports | RetrievalTask | c47d9617-ab99-4d6e-a6e6-92b8daf85a7d | Questions and answers based on PDFs containing tables and charts. The task provides the raw documents as well as factory methods to easily index them and create a retriever. Each example is composed of a question and reference answer. Success is measured based on the accuracy of the answer relative to the reference answer. We also measure the faithfulness of the model's response relative to the retrieved documents (if any). |
task = registry["Semi-structured Reports"]
task
| Name | Semi-structured Reports |
| Type | RetrievalTask |
| Dataset ID | c47d9617-ab99-4d6e-a6e6-92b8daf85a7d |
| Description | Questions and answers based on PDFs containing tables and charts. The task provides the raw documents as well as factory methods to easily index them and create a retriever. Each example is composed of a question and reference answer. Success is measured based on the accuracy of the answer relative to the reference answer. We also measure the faithfulness of the model's response relative to the retrieved documents (if any). |
| Retriever Factories | basic, parent-doc, hyde |
| Architecture Factories | |
| get_docs |
clone_public_dataset(task.dataset_id, dataset_name=task.name)
Dataset Semi-structured Reports already exists. Skipping.
You can access the dataset at https://smith.langchain.com/o/ebbaf2eb-769b-4505-aca2-d11de10372a4/datasets/f8f24935-cf57-4cb3-a30f-8df303a46962.
Now, index the documents#
You can see the raw filepaths, or use unstructured to process the pdfs.
from langchain_benchmarks.rag.tasks.semi_structured_reports import get_file_names
# If you want to completely customize the document processing, you can use the files directly
file_names = list(get_file_names())
from langchain.embeddings import HuggingFaceEmbeddings
embeddings = HuggingFaceEmbeddings(
model_name="thenlper/gte-base",
model_kwargs={"device": 0}, # Comment out to use CPU
)
# Arguments to pass to partition_pdf
unstructured_config = {
# Unstructured first finds embedded image blocks
"extract_images_in_pdf": False,
# Use layout model (YOLOX) to get bounding boxes (for tables) and find titles
# Titles are any sub-section of the document
"infer_table_structure": True,
# Post processing to aggregate text once we have the title
"chunking_strategy": "by_title",
# Chunking params to aggregate text blocks
# Attempt to create a new chunk 3800 chars
# Attempt to keep chunks > 2000 chars
"max_characters": 4000,
"new_after_n_chars": 3800,
"combine_text_under_n_chars": 2000,
}
docs = list(task.get_docs(unstructured_config=unstructured_config))
Some weights of the model checkpoint at microsoft/table-transformer-structure-recognition were not used when initializing TableTransformerForObjectDetection: ['model.backbone.conv_encoder.model.layer2.0.downsample.1.num_batches_tracked', 'model.backbone.conv_encoder.model.layer3.0.downsample.1.num_batches_tracked', 'model.backbone.conv_encoder.model.layer4.0.downsample.1.num_batches_tracked']
- This IS expected if you are initializing TableTransformerForObjectDetection from the checkpoint of a model trained on another task or with another architecture (e.g. initializing a BertForSequenceClassification model from a BertForPreTraining model).
- This IS NOT expected if you are initializing TableTransformerForObjectDetection from the checkpoint of a model that you expect to be exactly identical (initializing a BertForSequenceClassification model from a BertForSequenceClassification model).
retriever_factory = task.retriever_factories["basic"]
# Indexes the documents with the specified embeddings
retriever = retriever_factory(embeddings, docs=docs)
Chroma/semi-structured-earnings-b_Chroma_HuggingFaceEmbeddings_raw
[]
Time to evaluate#
We will compose our retriever with a simple Llama based LLM.
from langchain.chat_models import ChatAnthropic
from langchain.prompts import ChatPromptTemplate
from langchain.schema.output_parser import StrOutputParser
from langchain.schema.runnable.passthrough import RunnableAssign
def create_chain(retriever):
prompt = ChatPromptTemplate.from_messages(
[
(
"system",
"Answer based solely on the retrieved documents below:\n\n<Documents>\n{docs}</Documents>",
),
("user", "{question}"),
]
)
llm = ChatAnthropic(model="claude-2")
return (
RunnableAssign({"docs": (lambda x: next(iter(x.values()))) | retriever})
| prompt
| llm
| StrOutputParser()
)
from langsmith.client import Client
from langchain_benchmarks.rag import get_eval_config
client = Client()
RAG_EVALUATION = get_eval_config()
chain = create_chain(retriever)
test_run = client.run_on_dataset(
dataset_name=task.name,
llm_or_chain_factory=chain,
evaluation=RAG_EVALUATION,
verbose=True,
)
View the evaluation results for project 'cold-attachment-88' at:
https://smith.langchain.com/o/ebbaf2eb-769b-4505-aca2-d11de10372a4/projects/p/d8e512b7-b63d-4eb5-8d73-d95f7fa7ffc2?eval=true
View all tests for Dataset Semi-structured Reports at:
https://smith.langchain.com/o/ebbaf2eb-769b-4505-aca2-d11de10372a4/datasets/f8f24935-cf57-4cb3-a30f-8df303a46962
[------------------------------------------------->] 5/5
Eval quantiles:
inputs.question \
count 5
unique 5
top Analyzing the operating expenses for Q3 2023, ...
freq 1
mean NaN
std NaN
min NaN
25% NaN
50% NaN
75% NaN
max NaN
feedback.embedding_cosine_distance feedback.faithfulness \
count 5.000000 5.0
unique NaN NaN
top NaN NaN
freq NaN NaN
mean 0.137066 1.0
std 0.011379 0.0
min 0.123112 1.0
25% 0.129089 1.0
50% 0.137871 1.0
75% 0.143398 1.0
max 0.151860 1.0
feedback.score_string:accuracy error execution_time
count 5.0 0 5.000000
unique NaN 0 NaN
top NaN NaN NaN
freq NaN NaN NaN
mean 0.1 NaN 7.940625
std 0.0 NaN 1.380190
min 0.1 NaN 6.416387
25% 0.1 NaN 7.272528
50% 0.1 NaN 7.324673
75% 0.1 NaN 8.831243
max 0.1 NaN 9.858293
Example processing the docs#
RAG apps are as good as the information they are able to retrieve. Let’s try indexing the tables’ summaries to improve the likelihood that they are retrieved whenever a user asks a relevant question.
We will use unstructured’s partition_pdf functionality and generate summaries using an LLM.
You can define your own indexing pipeline to see how it impacts the downstream performance.
from operator import itemgetter
from langchain.chat_models import ChatOpenAI
from langchain.prompts import ChatPromptTemplate
from langchain.schema.document import Document
from langchain.schema.output_parser import StrOutputParser
from langchain.schema.runnable.passthrough import RunnableAssign
# Prompt
prompt = ChatPromptTemplate.from_messages(
[
(
"system",
"You are summarizing semi-structured tables or text in a pdf.\n\n```document\n{doc}\n```",
),
("user", "Write a concise summary."),
]
)
# Summary chain
model = ChatOpenAI(temperature=0, model="gpt-3.5-turbo-16k")
def create_doc(x) -> Document:
return Document(
page_content=x["output"],
metadata=x["doc"].metadata,
)
summarize_chain = (
{"doc": lambda x: x}
| RunnableAssign({"prompt": prompt})
| {
"output": itemgetter("prompt") | model | StrOutputParser(),
"doc": itemgetter("doc"),
}
| create_doc
)
summaries = summarize_chain.batch(
[doc for doc in docs if doc.metadata["element_type"] == "table"]
)
Index the documents and create the retriever. We will re
# Indexes the documents with the specified embeddings
retriever_with_summaries = retriever_factory(
embeddings,
docs=docs + summaries,
# Specify a unique transformation name to avoid local cache collisions with other indices.
transformation_name="docs-with_summaries",
)
Evaluate#
We’ll evaluate the new chain on the same dataset.
chain_2 = create_chain(retriever_with_summaries)
test_run_with_summaries = client.run_on_dataset(
dataset_name=task.name,
llm_or_chain_factory=chain_2,
evaluation=RAG_EVALUATION,
verbose=True,
)
View the evaluation results for project 'crazy-harmony-39' at:
https://smith.langchain.com/o/ebbaf2eb-769b-4505-aca2-d11de10372a4/projects/p/b69d796f-6ba4-4cde-822f-db363cf81f8f?eval=true
View all tests for Dataset Semi-structured Reports at:
https://smith.langchain.com/o/ebbaf2eb-769b-4505-aca2-d11de10372a4/datasets/f8f24935-cf57-4cb3-a30f-8df303a46962
[------------------------------------------------->] 5/5
Eval quantiles:
inputs.question \
count 5
unique 5
top Analyzing the operating expenses for Q3 2023, ...
freq 1
mean NaN
std NaN
min NaN
25% NaN
50% NaN
75% NaN
max NaN
feedback.score_string:accuracy feedback.faithfulness \
count 5.000000 5.0
unique NaN NaN
top NaN NaN
freq NaN NaN
mean 0.720000 1.0
std 0.408656 0.0
min 0.100000 1.0
25% 0.500000 1.0
50% 1.000000 1.0
75% 1.000000 1.0
max 1.000000 1.0
feedback.embedding_cosine_distance error execution_time
count 5.000000 0 5.000000
unique NaN 0 NaN
top NaN NaN NaN
freq NaN NaN NaN
mean 0.069363 NaN 8.659120
std 0.023270 NaN 2.611724
min 0.039593 NaN 6.283505
25% 0.050176 NaN 6.723136
50% 0.078912 NaN 7.441743
75% 0.084389 NaN 10.673265
max 0.093747 NaN 12.173952