Table of Contents


grape4 - sample operations on GRAPE4


Currently only a reminder to some operational details for the GRAPE4 in Drexel.


Demo versions harp3 and harp3X expect input files in ascii "205" (see stoa(1NEMO) ) format or create initial data on the fly. The output (also optional) format however is in binary "205" format (see also atos(1NEMO) , with the binary=true option), and this needs to be converted on the host to tag the proper endianism in snapshot(5NEMO) files.

The direct4(1NEMO) demo program is a condensed version of the harp3 demo, but expects standard NEMO datafiles.


Here is a parameter input file for harp3, to be run as follows:
    % harp3 < run1.par
    % atos run1.out - binary=t options=mass,phase,phi |\
        snapxyz - - | xyzview - scale=4 maxframe=200

where run1.par looks as follows: (did somebody mix up dtout and dtsnapout?)

16384 0.03125 25 1 0.03125  0.25 8
1 0.2
2         <-- never used?


The following NEMO chain of commands should be the same as the harp3 demo just shown:
mkhomsph - 16384 rmax=1 vmax=0.2 |\
    snapspin - - omega=-0.8 |\
    direct4 - . dt=0.03125 tstop=25 dtlog=0.03125 dtout=1 eps=0.25 

See Also

direct4(1NEMO) , atos(1NEMO) , stoa(1NEMO) , snapshot(5NEMO)


Peter Teuben


The following environment variables are expected by the GRAPE4 board:
HARP3_NBOARDS        number of board you have [Drexel: 1]
HARP3_NCLUSTERS          number of clusters [Drexel: 1]
HARP3_FIRSTCLUSTER      first cluster [Drexel: 0]
HARP3_DEFECTS             file with list of defects [Drexel: ~makino/src/harplibs/defect_list]

Update History

21-may-97    Created      PJT

Table of Contents