Basic HTML version of Foils prepared 22 February 1998

Foil 36 Simple Data Parallel Version of N Body Force Computation -- Grav -- I

From Fox Presentation Fall 1995 CPS615 Basic Simulation Track for Computational Science -- 1998 Enhancements. by Geoffrey C. Fox
1 function Grav(X,M)
2 C accepts positions of particles X and masses of particles M
3 C returns accelerations in Grav
4 C Uses completely parallel calculation, ignoring anti-symmetry of force
  • integer, parameter :: N =number of particles
  • real, parameter :: G = gravitational constant
  • real array (1:3, 1:N) :: X,M,Grav
5 ! calculates acceleration on body i due to body j in entries ( :,i,j )
  • real array (1:3, 1:N,1:N) :: A, Xi, Xj, Ms, D, R
  • logical, array (1:3, 1:N,1:N) ::diag
  • integer i,j,k
6 ! diag is true for diagonal of N by N slices
  • forall ( k=1:3, i=1:N, j=1:N ) diag = (i.eq.j)
in Table To:

© 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 Sun Feb 22 1998