Hello,
I noticed that I have no problems running more than 2ˆ31 timesteps when writing to text dump files.
However, writing to binary files like dcd and xtc, lammps exits when hitting 2^31 timesteps with the error
ERROR: Too big a timestep for dump dcd (dump.dcd.cpp:129)
Is this a bug in lammps, a general restriction of dcd files, or some other problem?
I noticed that I can manually write dcd files that contain timesteps larger than 2^31, for example using MDAnalysis.
I am running a lammps build from 9 Nov 2011 on linux AMD 64.
Hello,
I noticed that I have no problems running more than 2ˆ31 timesteps when writing to text dump files.
However, writing to binary files like dcd and xtc, lammps exits when hitting 2^31 timesteps with the error
ERROR: Too big a timestep for dump dcd (dump.dcd.cpp:129)
Is this a bug in lammps, a general restriction of dcd files, or some other problem?
the field in the dcd file that contains the timestep
number is a signed 32-bit integer, so you cannot
write larger time step numbers to the dcd file.
just use reset_timestep to keep the time step
number within 32-bits if you want to use dcd
or xtc format files.
I noticed that I can manually write dcd files that contain timesteps larger than 2^31, for example using MDAnalysis.
but do they contain the correct time step number?
most likely that number is wrapped around or else
the format would not be correct.
axel.