[lammps-users] many fix and many run in a simulation

Hello everyone!
my input file is :
    ............
fix 1 all nve
run 5000

    .............

fix 2 all temp/rescale 1300 300 5000 0.5 1
fix 3 all msd 5000 msd.out
fix 4 all rdf 5000 rdf.out 100 1 1

   ..........

run 100000

My question is:

a. If the valid of " fix 1 "is extended to the second " run"
b. when the "every timestep- 5000 " in "fix 2" is different from
that in "the thermo", does the log file have some different?
c. if we want to use fix NVT in " the second run ",then how we
modify it. is it right that we use :
   .............

unfix 1
fix 1 nvt .....
fix 2 ...........
fix 3 all msd 5000 msd.out
fix 4 all rdf 5000 rdf.out 100 1 1

   ..........

run 100000

d. if the input data (velocity and position ) of " the second run "
is followed the end data of "the first run "

e. which is good we use many run in one input file or one run in many
input file?

your answer is very appreciated! thanks .

Lu,

a. If the valid of " fix 1 "is extended to the
second " run"

Yes, that fix continues to be imposed until you tell
LAMMPS to stop imposing it using the unfix command:
"unfix 1".

b. when the "every timestep- 5000 " in "fix 2" is >

different from

that in "the thermo", does the log file have some >

different?

No, the log file should have the print frequency
designated in the "thermo" command, irregardless of
what is designated in fix 2.

c. if we want to use fix NVT in " the second
run ",then how we modify it. is it right that we
use :

   .............

unfix 1
fix 1 nvt .....
fix 2 ...........
fix 3 all msd 5000 msd.out
fix 4 all rdf 5000 rdf.out 100 1 1

   ..........

run 100000

Yes, this is correct.

d. if the input data (velocity and position ) >

of " the second run " is followed the end data >
of "the first run "

Yes, the velocities and positions at the beginning of
the second run command will be identical to those at
the end of the first run command.

e. which is good we use many run in one input
file or one run in many input file?

Either way. It really depends on what you're trying to
do. I would generally advise many run commands in one
input file rather than one run command in many input
files.

Paul