NBSymple，一个在图形处理单元上运行的双并行辛N体代码
NBSymple, a double parallel, symplectic N-body code running on Graphic Processing Units
摘要：
本文介绍并讨论了一个数值积分N个粒子在银河系外光滑场中通过牛顿引力相互作用的运动方程的数值程序的特点和性能，包括计算速度和精度。每个质点的受力计算是通过直接求和其他质点的贡献来完成的，避免了截断误差。时间积分采用二阶和六阶辛格式。代码NBSymple通过计算机统一设备体系结构（Computer Unified Device Architecture）进行了两次并行化，以使所有对力的计算尽可能快地在高性能图形处理单元NVIDIA TESLA C 1060上进行，而O（N）计算则通过OpenMP应用程序分布在不同的CPU上。该代码既可以在单精度浮点运算中工作，也可以在双精度中工作。使用单精度允许使用最好的GPU性能，但当然，在某些关键情况下限制了模拟的精度。我们找到了一个很好的妥协，在使用软件重建的双精度的那些变量是最关键的整体精度的代码。该代码可在网站astrowww.phys.uniroma1.it/dolcetta/nbsymple.html上获得
英文摘要：
We present and discuss the characteristics and performances, both in term of computational speed and precision, of a numerical code which numerically integrates the equation of motions of N 'particles' interacting via Newtonian gravitation and move in an external galactic smooth field. The force evaluation on every particle is done by mean of direct summation of the contribution of all the other system's particle, avoiding truncation error. The time integration is done with second-order and sixth-order symplectic schemes. The code, NBSymple, has been parallelized twice, by mean of the Computer Unified Device Architecture to make the all-pair force evaluation as fast as possible on high-performance Graphic Processing Units NVIDIA TESLA C 1060, while the O(N) computations are distributed on various CPUs by mean of OpenMP Application Program. The code works both in single precision floating point arithmetics or in double precision. The use of single precision allows the use at best of the GPU performances but, of course, limits the precision of simulation in some critical situations. We find a good compromise in using a software reconstruction of double precision for those variables that are most critical for the overall precision of the code. The code is available on the web site astrowww.phys.uniroma1.it/dolcetta/nbsymple.html
机构、总结、中文摘要均由AI分析而来，可能存在错误，请以论文正文为准。
