PointNeighbors.jl

PointNeighbors.jl is a package for neighborhood search with fixed search radius in 1D, 2D and 3D point clouds.

Features

• Several implementations of neighborhood search with fixed search radius
• Focus on fast incremental updates to be usable for particle-based simulations with frequent updates
• Designed as a "playground" to easily switch between different implementations and data structures
• Common API over all implementations
• Extensive benchmark suite to study different implementations (work in progress)
• GPU compatibility (work in progress)

Implementation	Description	Features	Query	Update	GPU-compatible
GridNeighborhoodSearch with DictionaryCellList	Grid-based NHS with Julia Dict backend	Infinite domain	Fast	Fast	❌
GridNeighborhoodSearch with FullGridCellList	Grid-based NHS allocating all cells of the domain	Finite domain, but efficient memory layout for densely filled domain.	Faster	Fastest	✅
PrecomputedNeighborhoodSearch	Precompute neighbor lists	Best for TLSPH without NHS updates. Not suitable for updates in every time step.	Fastest	Very slow	❌

Benchmarks

The following benchmarks were conducted on an AMD Ryzen Threadripper 3990X using 128 threads.

Benchmark of a single force computation step of a Weakly Compressible SPH (WCSPH) simulation:

Benchmark of an incremental update similar to a WCSPH simulation (note the log scale):

Benchmark of a full right-hand side evaluation of a WCSPH simulation (note the log scale):

Packages using PointNeighbors.jl

• TrixiParticles.jl
• Peridynamics.jl
• PeriLab.jl

If you're using PointNeighbors.jl in your package, please feel free to open a PR adding it to this list.

Cite Us

If you use PointNeighbors.jl in your own research or write a paper using results obtained with the help of PointNeighbors.jl, please cite it as

@misc{pointneighbors,
  title={{P}oint{N}eighbors.jl: {N}eighborhood search with fixed search radius in {J}ulia},
  author={Erik Faulhaber and Niklas Neher and Sven Berger and
          Michael Schlottke-Lakemper and Gregor Gassner},
  year={2024},
  howpublished={\url{https://github.com/trixi-framework/PointNeighbors.jl}},
  doi={10.5281/zenodo.12702157}
}