These pair styles will not restart exactly when using the +read_restart command, though they should provide +statistically similar results. This is because the forces they +compute depend on atom velocities. See the +read_restart command for more details. +
Related commands:
pair_coeff, fix nvt, fix diff --git a/doc/pair_dpd.txt b/doc/pair_dpd.txt index d2f8b38572..8b5f4fb903 100644 --- a/doc/pair_dpd.txt +++ b/doc/pair_dpd.txt @@ -166,6 +166,12 @@ These pair styles requires you to use the "communicate vel yes"_communicate.html option so that velocites are stored by ghost atoms. +These pair styles will not restart exactly when using the +"read_restart"_read_restart.html command, though they should provide +statistically similar results. This is because the forces they +compute depend on atom velocities. See the +"read_restart"_read_restart.html command for more details. + [Related commands:] "pair_coeff"_pair_coeff.html, "fix nvt"_fix_nh.html, "fix diff --git a/doc/pair_gran.html b/doc/pair_gran.html index eb452764c6..dca77cd6de 100644 --- a/doc/pair_gran.html +++ b/doc/pair_gran.html @@ -242,6 +242,12 @@ all of this. yes option so that velocites are stored by ghost atoms.
+These pair styles will not restart exactly when using the +read_restart command, though they should provide +statistically similar results. This is because the forces they +compute depend on atom velocities. See the +read_restart command for more details. +
Related commands:
pair_coeff diff --git a/doc/pair_gran.txt b/doc/pair_gran.txt index 1027bb77f1..7c6955d173 100644 --- a/doc/pair_gran.txt +++ b/doc/pair_gran.txt @@ -228,6 +228,12 @@ This pair style requires you to use the "communicate vel yes"_communicate.html option so that velocites are stored by ghost atoms. +These pair styles will not restart exactly when using the +"read_restart"_read_restart.html command, though they should provide +statistically similar results. This is because the forces they +compute depend on atom velocities. See the +"read_restart"_read_restart.html command for more details. + [Related commands:] "pair_coeff"_pair_coeff.html diff --git a/doc/pair_lubricate.html b/doc/pair_lubricate.html index 701e9f7d0f..198d1dcb60 100644 --- a/doc/pair_lubricate.html +++ b/doc/pair_lubricate.html @@ -206,6 +206,12 @@ lubricate.
Only spherical particles are allowed for pair_style lubricate/poly.
+These pair styles will not restart exactly when using the +read_restart command, though they should provide +statistically similar results. This is because the forces they +compute depend on atom velocities. See the +read_restart command for more details. +
Related commands:
pair_coeff, pair_style diff --git a/doc/pair_lubricate.txt b/doc/pair_lubricate.txt index 9362a312c3..b6d1149c87 100644 --- a/doc/pair_lubricate.txt +++ b/doc/pair_lubricate.txt @@ -200,6 +200,12 @@ lubricate. Only spherical particles are allowed for pair_style lubricate/poly. +These pair styles will not restart exactly when using the +"read_restart"_read_restart.html command, though they should provide +statistically similar results. This is because the forces they +compute depend on atom velocities. See the +"read_restart"_read_restart.html command for more details. + [Related commands:] "pair_coeff"_pair_coeff.html, "pair_style diff --git a/doc/read_restart.html b/doc/read_restart.html index 641ed0a57d..9a993d5ef2 100644 --- a/doc/read_restart.html +++ b/doc/read_restart.html @@ -33,18 +33,32 @@ stored in a restart file is given below.
Restart files are saved in binary format to enable exact restarts, meaning that the trajectories of a restarted run will precisely match -those produced by the original run had it continued on. Several -things can prevent exact restarts due to round-off effects, in which -case the trajectories in the 2 runs will slowly diverge. These +those produced by the original run had it continued on. +
+Several things can prevent exact restarts due to round-off effects, in +which case the trajectories in the 2 runs will slowly diverge. These include running on a different number of processors or changing certain settings such as those set by the newton or processors commands. LAMMPS will issue a warning in -these cases. Certain fixes will also not restart exactly, though they -should provide statistically similar results. These include fix -shake and fix langevin. If a -restarted run is immediately different than the run which produced the -restart file, it could be a LAMMPS bug, so consider reporting -it if you think the behavior is wrong. +these cases. +
+Certain fixes will not restart exactly, though they should provide +statistically similar results. These include fix +shake and fix langevin. +
+Certain pair styles will not restart exactly, though they should +provide statistically similar results. This is because the forces +they compute depend on atom velocities, which are used at half-step +values every timestep when forces are computed. When a run restarts, +forces are initiall evaluated with a full-step velocity, which is +different than if the run had continued. These pair styles include +granular pair styles, pair dpd, and +pair lubricate. +
+If a restarted run is immediately different than the run which +produced the restart file, it could be a LAMMPS bug, so consider +reporting it if you think the behavior is +wrong.
Because restart files are binary, they may not be portable to other machines. They can be converted to ASCII data files using the @@ -132,6 +146,8 @@ criteria including settings made via the neigh_modify comand, dump file output, geometric regions, etc.
+Restrictions: none
Related commands: diff --git a/doc/read_restart.txt b/doc/read_restart.txt index 10e73c5f3b..b8fcc84d27 100644 --- a/doc/read_restart.txt +++ b/doc/read_restart.txt @@ -30,18 +30,32 @@ stored in a restart file is given below. Restart files are saved in binary format to enable exact restarts, meaning that the trajectories of a restarted run will precisely match -those produced by the original run had it continued on. Several -things can prevent exact restarts due to round-off effects, in which -case the trajectories in the 2 runs will slowly diverge. These +those produced by the original run had it continued on. + +Several things can prevent exact restarts due to round-off effects, in +which case the trajectories in the 2 runs will slowly diverge. These include running on a different number of processors or changing certain settings such as those set by the "newton"_newton.html or "processors"_processors.html commands. LAMMPS will issue a warning in -these cases. Certain fixes will also not restart exactly, though they -should provide statistically similar results. These include "fix -shake"_fix_shake.html and "fix langevin"_fix_langevin.html. If a -restarted run is immediately different than the run which produced the -restart file, it could be a LAMMPS bug, so consider "reporting -it"_Section_errors.html#err_2 if you think the behavior is wrong. +these cases. + +Certain fixes will not restart exactly, though they should provide +statistically similar results. These include "fix +shake"_fix_shake.html and "fix langevin"_fix_langevin.html. + +Certain pair styles will not restart exactly, though they should +provide statistically similar results. This is because the forces +they compute depend on atom velocities, which are used at half-step +values every timestep when forces are computed. When a run restarts, +forces are initiall evaluated with a full-step velocity, which is +different than if the run had continued. These pair styles include +"granular pair styles"_pair_gran.html, "pair dpd"_pair_dpd.html, and +"pair lubricate"_pair_lubricate.html. + +If a restarted run is immediately different than the run which +produced the restart file, it could be a LAMMPS bug, so consider +"reporting it"_Section_errors.html#err_2 if you think the behavior is +wrong. Because restart files are binary, they may not be portable to other machines. They can be converted to ASCII data files using the @@ -129,6 +143,8 @@ criteria including settings made via the "neigh_modify"_doc/neigh_modify.html comand, "dump"_dump.html file output, "geometric regions"_region.html, etc. +:line + [Restrictions:] none [Related commands:]