pgvector examples for Fortran
Supports Libpq-Fortran
Follow the instructions for your database library:
Enable the extension
type(c_ptr) :: res
res = PQexec(conn, "CREATE EXTENSION IF NOT EXISTS vector")Create a table
res = PQexec(conn, "CREATE TABLE items (id bigserial PRIMARY KEY, embedding vector(3))")Insert vectors
character(256) :: values(2)
values(1) = "[1,2,3]"
values(2) = "[4,5,6]"
res = PQexecParams(conn, "INSERT INTO items (embedding) VALUES ($1), ($2)", 2, [0, 0], values)Get the nearest neighbors
character(256) :: values(1)
values(1) = "[3,1,2]"
res = PQexecParams(conn, "SELECT * FROM items ORDER BY embedding <-> $1 LIMIT 5", 1, [0], values)Add an approximate index
res = PQexec(conn, "CREATE INDEX ON items USING hnsw (embedding vector_l2_ops)")
! or
res = PQexec(conn, "CREATE INDEX ON items USING ivfflat (embedding vector_l2_ops) WITH (lists = 100)")Use vector_ip_ops for inner product and vector_cosine_ops for cosine distance
See a full example
Everyone is encouraged to help improve this project. Here are a few ways you can help:
- Report bugs
- Fix bugs and submit pull requests
- Write, clarify, or fix documentation
- Suggest or add new features
To get started with development:
git clone https://github.com/pgvector/pgvector-fortran.git
cd pgvector-fortran
createdb pgvector_fortran_test
fpm runSpecify the path to libpq if needed:
FPM_CFLAGS="-I/opt/homebrew/opt/libpq/include" FPM_LDFLAGS="-L/opt/homebrew/opt/libpq/lib" fpm run