lammps/lib/cuda/pair_buck_cuda_kernel_nc.cu

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/* ----------------------------------------------------------------------
LAMMPS - Large-scale Atomic/Molecular Massively Parallel Simulator
Original Version:
http://lammps.sandia.gov, Sandia National Laboratories
Steve Plimpton, sjplimp@sandia.gov
See the README file in the top-level LAMMPS directory.
-----------------------------------------------------------------------
USER-CUDA Package and associated modifications:
https://sourceforge.net/projects/lammpscuda/
Christian Trott, christian.trott@tu-ilmenau.de
Lars Winterfeld, lars.winterfeld@tu-ilmenau.de
Theoretical Physics II, University of Technology Ilmenau, Germany
See the README file in the USER-CUDA directory.
This software is distributed under the GNU General Public License.
------------------------------------------------------------------------- */
__device__ inline F_CFLOAT PairBuckCuda_Eval(const F_CFLOAT &rsq, const int ij_type, F_CFLOAT &factor_lj, int &eflag, ENERGY_CFLOAT &evdwl)
{
const F_CFLOAT r2inv = F_F(1.0) / rsq;
const F_CFLOAT r6inv = r2inv * r2inv * r2inv;
const F_CFLOAT r = _RSQRT_(r2inv);
const F_CFLOAT rexp = _EXP_(-r * _rhoinv[ij_type]);
const F_CFLOAT forcebuck = _buck1[ij_type] * r * rexp - _buck2[ij_type] * r6inv;
if(eflag) evdwl += factor_lj * (_a[ij_type] * rexp - _c[ij_type] * r6inv -
_offset[ij_type]);
return (factor_lj * forcebuck) * r2inv;
}