PHYSICS 141/241

Winter 2013

Laboratory Session IV.

C and Fortran Practice with the Aarseth Code

  • nbody0.tar.gz (Fortran code)

  • There are instruction below how to run the Fortran code.
  • nbody0-lab.c  C code 


  • Running the C code:
  • Compilation of C code: gcc -o xnbody nbody0-lab.c -lm
  • To run: xnbody reads in file and ouputs 
  •  has 1 header line plus one line for each particle in 7 columns: mass, x, y, z, vx, vy, vz
  • header line of has 5 data: # of particles, eta=0.02, dt, tmax, epsilon**2=0.25
  • has 4 columns: mass, x, y, z

  • Running the Fortran code:
  • Save, gunzip and untar in a directory:

    gunzip nbody0.tar.gz

    tar tvf nbody0.tar

    tar xvf nbody0.tar


    gunzip -d -c nbody.tar.gz | tar xvf -

  • Compile the Fortran code:

    gfortran -o xrun main.f nbody0.f nbodyio.f

  • Generate initial star distribution with 2000 points

  • Run the test program first

    xnb0 < &

  • Visualize and animate with DX