mirror of
https://github.com/hwchase17/langchain
synced 2024-11-04 06:00:26 +00:00
48 lines
1.3 KiB
Python
48 lines
1.3 KiB
Python
from pathlib import Path
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from langchain.document_loaders import TextLoader
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from langchain.embeddings.openai import OpenAIEmbeddings
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from langchain.graphs import Neo4jGraph
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from langchain.text_splitter import TokenTextSplitter
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from langchain.vectorstores import Neo4jVector
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txt_path = Path(__file__).parent / "dune.txt"
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graph = Neo4jGraph()
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# Load the text file
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loader = TextLoader(str(txt_path))
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documents = loader.load()
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# Define chunking strategy
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parent_splitter = TokenTextSplitter(chunk_size=512, chunk_overlap=24)
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child_splitter = TokenTextSplitter(chunk_size=100, chunk_overlap=24)
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# Store parent-child patterns into graph
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parent_documents = parent_splitter.split_documents(documents)
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for parent in parent_documents:
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child_documents = child_splitter.split_documents([parent])
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params = {
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"parent": parent.page_content,
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"children": [c.page_content for c in child_documents],
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}
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graph.query(
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"""
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CREATE (p:Parent {text: $parent})
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WITH p
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UNWIND $children AS child
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CREATE (c:Child {text: child})
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CREATE (c)-[:HAS_PARENT]->(p)
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""",
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params,
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)
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# Calculate embedding values on the child nodes
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Neo4jVector.from_existing_graph(
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OpenAIEmbeddings(),
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index_name="retrieval",
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node_label="Child",
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text_node_properties=["text"],
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embedding_node_property="embedding",
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)
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