Update llamaindex.adoc

added example

modules/genai-ecosystem/pages/llamaindex.adoc

@@ -16,6 +16,58 @@ LlamaIndex provides a lot of detailed examples for GenAI application development
 
 The Neo4j integration covers both the vector store as well as query generation from natural language and knowledge graph construction.
 
+== Example Usage
+
+[source,python]
+----
+%pip install llama-index-llms-openai
+%pip install llama-index-graph-stores-neo4j
+%pip install llama-index-embeddings-openai
+%pip install neo4j
+
+from llama_index.llms.openai import OpenAI
+from llama_index.embeddings.openai import OpenAIEmbedding
+from llama_index.core import (
+    VectorStoreIndex,
+    SimpleDirectoryReader,
+    KnowledgeGraphIndex,
+    Settings
+)
+from llama_index.graph_stores.neo4j import Neo4jGraphStore
+
+llm = OpenAI(temperature=0, model="gpt-3.5-turbo")
+embedding_llm = OpenAIEmbedding(model="text-embedding-ada-002")
+
+Settings.llm = llm
+Settings.embed_model = embedding_llm
+Settings.chunk_size = 512
+
+documents = SimpleDirectoryReader(
+    "../../../../examples/paul_graham_essay/data"
+).load_data()
+
+graph_store = Neo4jGraphStore(username=username,password=password,
+    url=url,database=database)
+
+storage_context = StorageContext.from_defaults(graph_store=graph_store)
+
+index = KnowledgeGraphIndex.from_documents(documents,
+    storage_context=storage_context, max_triplets_per_chunk=2,
+    include_embeddings=True
+)
+
+query_engine = index.as_query_engine(
+    include_text=True,
+    response_mode="tree_summarize",
+    embedding_mode="hybrid",
+    similarity_top_k=5,
+)
+
+response = query_engine.query(
+    "Tell me more about what the author worked on at Interleaf"
+)
+----
+
 == Documentation
 
 * https://docs.llamaindex.ai/en/latest/examples/index_structs/knowledge_graph/Neo4jKGIndexDemo.html[Neo4jKGIndexDemo^]