Thank u for ur response..n sory for the delay
i have try to put . but then it still can an error as below
[najdiah@UPMGrid ~]$ /opt/mpich/gnu/bin/mpirun -nolocal -np 4 -machinefile machines .$HOME/cpi
Missing: program name
Program ./home/najdiah/cpi either does not exist, is not
executable, or is an erroneous argument to mpirun.
thank u for ur response...