AMRVAC can be invoked with command line parameters, for example to do a restart run or to convert .dat files. The documentation for the command line parameters is available through:

./amrvac --help

which currently prints:

Usage example:
mpirun -np 4 ./amrvac -i file.par [file2.par ...]
         (later .par files override earlier ones)

Optional arguments:
-convert             Convert snapshot files
-if file0001.dat     Use this snapshot to restart from
                     (you can modify e.g. output names)
-resume              Automatically resume previous run
                     (useful for long runs on HPC systems)
-snapshotnext N      Manual index for next snapshot
-slicenext N         Manual index for next slice output
-collapsenext N      Manual index for next collapsed output

Examples

Using multiple par files

mpirun -np 4 ./amrvac -i file1.par file2.par

Note that settings from later par files override earlier ones. There is one exception to this: base_filename, for which the values are concatenated. Par files do not need to contain all the namelists (see Setting parameters).

Resume a previous simulation (which has not finished yet)

mpirun -np 4 ./amrvac -i amrvac.par -resume

This will automatically look for the last available snapshot (.dat) file and resume from it. Note that the indices for the next output files are automatically set. If the simulation was ended normally reaching wall time limit (see parameter wall_time_max to reach time limit of jobs on HPC systems), the resumed run will keep the previous output (time) cadence and overwrite the snapshot file from which the run resumed, so that the whole data series keep the same pace as if it was never stopped and resumed.

Restart a previous simulation from a specific snapshot

mpirun -np 4 ./amrvac -i amrvac.par -if output/sim0010.dat

To start the new output from a different index:

mpirun -np 4 ./amrvac -i amrvac.par -if output/sim0010.dat -snapshotnext 100

Convert a .dat file to another format

mpirun -np 4 ./amrvac -i amrvac.par -if output/sim0010.dat -convert

See Setting parameters for a list of formats (which should be specified in the .par file)