READ RESTART

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1

I run simulation for 10000 steps and then use read restart command to rerun simulation

In log file I get following result
Created orthogonal box = (0 0 0) to (21.04 21.04 21.04)

Step temp pressure volume total energy kinetic energy potenergy

10000 0.0095645167 1.1818814 9304.3409 -514.58319 0.0072700519 -514.59046

In restart log file I get following result
orthogonal box = (0.00364571 0.00364571 0.00364571) to (21.0364 21.0364 21.0364)
Step temp pressure volume total energy kinetic energy potenergy
10000 0.01 1.1835077 9304.3409 -514.58286 0.0076010656 -514.59046

The orthogonal box seems to be displaced and the values at 10000 step do not perfectly match. Will it not cause errors?

2

I run simulation for 10000 steps and then use read restart command to rerun
simulation

In log file I get following result
Created orthogonal box = (0 0 0) to (21.04 21.04 21.04)
Step temp pressure volume total energy
kinetic energy potenergy
10000 0.0095645167 1.1818814 9304.3409 -514.58319 0.0072700519
-514.59046

In restart log file I get following result
orthogonal box = (0.00364571 0.00364571 0.00364571) to (21.0364 21.0364
21.0364)
Step temp pressure volume total energy kinetic energy
potenergy
10000 0.01 1.1835077 9304.3409 -514.58286 0.0076010656
-514.59046

The orthogonal box seems to be displaced and the values at 10000 step do not
perfectly match. Will it not cause errors?

you are comparing apples and oranges.

the reported volume at step 10000 *is* identical and does not match
the volume of 21.04^3 reported in your first chunk of output, which
indicates that you are during a variable cell simulation and thus
comparing the box created at step 0 with the box extents at step
10000, which are *not* likely to match.

however, what should be serious concern is the fact that your kinetic
energy doesn't match, which likely means that you are doing some
manipulation there, that shouldn't be done.

axel.

3

Thanks for your reply.

I have one more question, If I run the simulation for N steps and the rerun from N+1 time step using restart commands. Then if I want to use fix npt in restart input script, What should be my Pstart and Tstart. I guess mean of previous N steps of Pressure and temperature to take as Pstart and Tstart . Or the values of pressure and temperature at nth step as Pstart and tstart.?

4

Thanks for your reply.

I have one more question, If I run the simulation for N steps and the
rerun from N+1 time step using restart commands. Then if I want to use fix
npt in restart input script, What should be my Pstart and Tstart. I guess
mean of previous N steps of Pressure and temperature to take as Pstart and
Tstart . Or the values of pressure and temperature at nth step as Pstart
and tstart.?

​please see the documentation of the relevant fix and the read_restart
command.

axel.​