To run FieldConvert in parallel the user needs to compile Nektar++ with MPI support and can employ the following command
mpirun -np <nprocs> FieldConvert test.xml test.fld test.dat
mpirun -np <nprocs> FieldConvert test.xml test.fld test.plt
or
mpirun -np <nprocs> FieldConvert test.xml test.fld test.vtu
replacing <nprocs> with the number of processors. For the .dat and .plt outputs the
current version will produce a single output file. However it is also sometimes useful to
produce multiple output files, one for each partition, and this can be done by using the
writemultiplefiles option, i.e.
mpirun -np <nprocs> FieldConvert test.xml test.fld \ test.dat:dat:writemultiplefiles
mpirun -np <nprocs> FieldConvert test.xml test.fld \ test.plt:plt:writemultiplefiles
For the .vtu format multiple files will by default be produced of the form test_vtu/P0000000.vtu,
test_vtu/P0000001.vtu, test_vtu/P0000002.vtu. For this format an additional file called
test.pvtu is written out which allows for parallel reading of the individual .vtu
files.
FieldConvert functions that produce a .fld file output will also be created when running in
parallel. In this case when producing a .fld file a directory called test.fld (or the
specified output name) is created with the standard parallel field files placed within the
directory.