ngt-rs
Rust wrappers for NGT, which provides high-speed approximate nearest neighbor
searches against a large volume of data in high dimensional vector data space (several
ten to several thousand dimensions). The vector data can be f32, u8, or f16.
This crate provides the following indexes:
NgtIndex: Graph and tree based index[^1]QgIndex: Quantized graph based index[^2]QbgIndex: Quantized blob graph based index
Both quantized indexes are available through the quantized Cargo feature. Note that
they rely on BLAS and LAPACK which thus have to be installed locally. Furthermore,
QgIndex performances can be improved by using the qg_optim Cargo
feature.
The NgtIndex default implementation is an ANNG. It can be optimized[^3] or converted
to an ONNG through the optim module.
By default ngt-rs will be built dynamically, which requires CMake to build NGT. This
means that you'll have to make the build artifact libngt.so available to your final
binary (see an example in the CI). However the static feature will build and
link NGT statically. Note that OpenMP will also be linked statically. If the
quantized feature is used, then BLAS and LAPACK libraries will also be linked
statically.
NGT's shared memory and large dataset features are
available through the Cargo features shared_mem and large_data respectively.
[^1]: Graph and tree based method explanation