English
Related papers

Related papers: A fast recursive coordinate bisection tree for nei…

200 papers

Tree codes that approximate groups of distant particles with multipole expansions are the standard way to accelerate the computation of self-gravity on particles. While momentum-conserving fast multipole methods exist, parallelisation is…

Instrumentation and Methods for Astrophysics · Physics 2026-02-06 Yann Bernard , Timothée David-Cléris , Daniel J. Price , Mike Y. M. Lau

The performance and accuracy of a GRAPE-3 system for collisionless N-body simulations is discussed. After a description of the hardware configurations available to us at Marseille, and the usefulness of on-line analysis, we concentrate on…

Astrophysics · Physics 2009-10-30 E. Athanassoula , A. Bosma , J. -C. Lambert , J. Makino

Fixed-radius near neighbor search is a fundamental data operation that retrieves all data points within a user-specified distance to a query point. There are efficient algorithms that can provide fast approximate query responses, but they…

Information Retrieval · Computer Science 2024-01-30 Xinye Chen , Stefan Güttel

A P3M (Particle-Particle, Particle-Mesh) algorithm to compute the gravitational force on a set of particles is described. The gravitational force is computed using Fast Fourier Transforms. This leads to an incorrect force when the distance…

Astrophysics · Physics 2009-10-22 T. Theuns

This paper describes a novel approach to neighbour-finding in Smoothed Particle Hydrodynamics (SPH) simulations with large dynamic range in smoothing length. This approach is based on hierarchical cell decompositions, sorted interactions,…

Instrumentation and Methods for Astrophysics · Physics 2013-09-17 Pedro Gonnet , Matthieu Schaller , Tom Theuns , Aidan B. G. Chalk

In this paper we introduce and study three new measures for efficient discriminative comparison of phylogenetic trees. The NNI navigation dissimilarity $d_{nav}$ counts the steps along a "combing" of the Nearest Neighbor Interchange (NNI)…

Populations and Evolution · Quantitative Biology 2015-10-21 Omur Arslan , Dan P. Guralnik , Daniel E. Koditschek

We have developed a parallel Particle-Particle, Particle-Mesh (P^3M) simulation code for the T3E well suited to studying the time evolution of systems of particles interacting via gravity and gas forces in cosmological contexts. The…

Astrophysics · Physics 2009-09-25 Tom MacFarland , Jakob Pichlmeier , Frazer Pearce , Hugh Couchman

Cosmological N-Body simulations are used for a variety of applications. Indeed progress in the study of large scale structures and galaxy formation would have been very limited without this tool. For nearly twenty years the limitations…

Astrophysics · Physics 2010-05-07 J. S. Bagla , Nishikanta Khandai

Proximity graph-based methods have emerged as a leading paradigm for approximate nearest neighbor (ANN) search in the system community. This paper presents fresh insights into the theoretical foundation of these methods. We describe an…

Data Structures and Algorithms · Computer Science 2025-09-10 Shangqi Lu , Yufei Tao

The block tree [Belazzougui et al., J. Comput. Syst. Sci. '21] is a compressed representation of a length-$n$ text that supports access, rank, and select queries while requiring only $O(z\log\frac{n}{z})$ words of space, where $z$ is the…

Data Structures and Algorithms · Computer Science 2025-12-30 Robert Clausecker , Florian Kurpicz , Etienne Palanga

In this paper, we describe the implementation and performance of GreeM, a massively parallel TreePM code for large-scale cosmological N-body simulations. GreeM uses a recursive multi-section algorithm for domain decomposition. The size of…

Instrumentation and Methods for Astrophysics · Physics 2015-05-14 Tomoaki Ishiyama , Toshiyuki Fukushige , Junichiro Makino

We develop the Blooming Tree Algorithm, a new technique that uses spectroscopic redshift data alone to identify the substructures and the surrounding groups of galaxy clusters, along with their member galaxies. Based on the estimated…

Astrophysics of Galaxies · Physics 2018-06-21 Heng Yu , Antonaldo Diaferio , Ana Laura Serra , Marco Baldi

We have developed a parallel Particle-Particle, Particle-Mesh (P3M) simulation code for the Cray T3E parallel supercomputer that is well suited to studying the time evolution of systems of particles interacting via gravity and gas forces in…

Astrophysics · Physics 2009-10-30 Tom MacFarland , H. M. P. Couchman , F. R. Pearce , Jakob Pichlmeier

We present space-efficient parallel strategies for two fundamental combinatorial search problems, namely, backtrack search and branch-and-bound, both involving the visit of an $n$-node tree of height $h$ under the assumption that a node can…

Data Structures and Algorithms · Computer Science 2014-03-27 Andrea Pietracaprina , Geppino Pucci , Francesco Silvestri , Fabio Vandin

This paper presents an octree construction method, called Cornerstone, that facilitates global domain decomposition and interactions between particles in mesh-free numerical simulations. Our method is based on algorithms developed for 3D…

Instrumentation and Methods for Astrophysics · Physics 2023-07-14 Sebastian Keller , Aurélien Cavelan , Rubén Cabezon , Lucio Mayer , Florina M. Ciorba

The simulation of electrical discharges has been attracting a great deal of attention. In such simulations, the electric field computation dominates the computational time. In this paper, we propose a fast tree algorithm that helps to…

Computational Engineering, Finance, and Science · Computer Science 2018-07-04 Chijie Zhuang , Yong Zhang , Xin Zhou , Rong Zeng , Jinliang He , Lei Liu

In this paper we present a new algorithm for learning oblique decision trees. Most of the current decision tree algorithms rely on impurity measures to assess the goodness of hyperplanes at each node while learning a decision tree in a…

Machine Learning · Computer Science 2012-10-16 Naresh Manwani , P. S. Sastry

The TREE method has been widely used for long-range interaction {\it N}-body problems. We have developed a parallel TREE code for two-component classical plasmas with open boundary conditions and highly non-uniform charge distributions. The…

Computational Physics · Physics 2009-05-04 Byoungseon Jeon , Joel D. Kress , Lee A. Collins , Niels Grønbech-Jensen

We demonstrate a new geometric method for fast template placement for searches for gravitational waves from the inspiral, merger and ringdown of compact binaries. The method is based on a binary tree decomposition of the template bank…

The approximate computation of all gravitational forces between $N$ interacting particles via the fast multipole method (FMM) can be made as accurate as direct summation, but requires less than $\mathcal{O}(N)$ operations. FMM groups…

Instrumentation and Methods for Astrophysics · Physics 2014-05-12 Walter Dehnen