dot_product
Generic Description
Computes the vector dot product for equal-length numeric vectors. It is documented separately because similarity orientation, vector dimensions, and set semantics directly affect ranking and interpretation.
Simple example:
RETURN dot_product(vector([1.0, 2.0]), vector([3.0, 4.0])) AS value
Consumer-Level Explanation
Use it when vector magnitude is intentionally part of the score. Prefer this function when symbolic graph filters and similarity evidence should remain in one auditable Cypher pipeline.
More Detailed Explanation
dot_product keeps similarity scoring in the same Cypher pipeline as symbolic graph filters and document metadata checks. That lets a query combine labels, relationships, time filters, and embedding or set overlap scores without asking a client to reconcile separate result sets.
Advanced Example
This example applies dot_product after symbolic graph filtering, which keeps hybrid retrieval constraints and similarity scoring in one visible pipeline.
MATCH (d:Document)
WITH d, dot_product(vector(properties(d).embedding), vector([0.22, 0.18, 0.44])) AS weighted_embedding_score
RETURN d.title AS document, weighted_embedding_score
ORDER BY weighted_embedding_score DESC
Real Use Cases
- semantic ranking over embedded documents after graph/time filtering
- link-prediction features based on shared neighbors or metadata overlap
- hybrid retrieval where symbolic constraints and vector scores are both visible
Real Limitations And Tradeoffs
- vector functions require compatible dimensions and meaningful embedding spaces
- set-similarity functions treat lists as sets and may ignore duplicate frequency
- a high similarity score is evidence, not proof of domain equivalence