Basic HTML version of Foils prepared 14 October 1997

Foil 42 Data Parallel Grav Pipeline Algorithm, concluded

From Fox Presentation Fall 1995 CPS615 Basic Simulation Track for Computational Science -- Fall Semester 95/96/97. by Nancy McCracken and Geoffrey C. Fox
if (( N mod 2) = 0 ) then ! final one way acceleration if N even
  • Xc = cshift (Xc, dim=2, shift = -1)
  • Mc = cshift (Mc, dim=2, shift = -1)
  • Ac = cshift (Ac, dim=2, shift = -1)
  • D = Xc-X
  • R = sqrt (spread (sum (D*D, dim=1), dim=1, ncopies=3)))
  • D = D/R**3
  • A = A + Mc*D
end if
! combine accelerations for final result - circulating particle in i'th
! position corresponds to fixed particle (i-(N-1)/2)
Grav = A + cshift (Ac, dim=2, shift = (N-1)/2)
end function Grav

© Northeast Parallel Architectures Center, Syracuse University, npac@npac.syr.edu

If you have any comments about this server, send e-mail to webmaster@npac.syr.edu.

Page produced by wwwfoil on Fri Oct 2 1998