This page shows how to run a first problem after the Installation is completed.

The VAC problem

Traditionally, the first test problem is the VAC advection located in amrvac/tests/rho/vac. Two files are present in this folder:

mod_usr.t: the user code for this problem (defining e.g. initial conditions)
amrvac.par: a text file with settings

Compilation

In the vac test folder, run the setup script with:

setup.pl -d=2

This will copy a makefile to the current folder, set the problem dimension to two, and use the default compiler settings, which is mpif90 (gfortran with openMPI). To select different compiler settings, check files in amrvac/arch/.

Then, to compile the code according to the makefile with 4 processors:

make -j4

To switch to using intel compiler mpiifort, you could modify the makefile and compile:

setup.pl -d=2 -arch=intel
make -j4

or you can keep the makefile and switch compiler once with compiling command:

make -j4 ARCH=intel

This will perform a parallel compilation using 4 cores. First, the AMRVAC library is compiled under amrvac/lib/ in a folder named by dimension and arch name, if it is not available already. This is the generic part of AMRVAC that does not depend on your user code. Then your user code mod_usr.t is also compiled, and an executable binary file called amrvac is produced.

There are a couple of useful commands to know about:

make ARCH=debug   # do a gfortran debug compilation (extra error checking and running error message)
make ARCH=<name>  # use the compilation flags from amrvac/arch/<name>.defs
make clean        # clean the local object files
make allclean     # clean the local object files and the AMRVAC library

Running the test

To run the test problem on 4 cores:

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

This will run amrvac with parameter-file amrvac.par. Then you have several new files ending in .dat, .vtu and one .log file. The .dat files are used for restarts and the .vtu files contain the output data to be visualized.

Visualization

Simulation output in .vtu (VTK unstructured) format can directly be visualized using Paraview or Visit.

Visualization or analysis of the results can also be done by converting .dat files to e.g., Tecplot, or VTK native formats. This requires the same amrvac executable used to run the simulation. Using a csh script tool aiconvert in amrvac/tools folder, users can convert to a format defined by convert_type parameter in the filelist of an input par file:

aiconvert

to convert all .dat files related to amrvac.par file, or

aiconvert 10 20

from snapshot 10 to 20, or

aiconvert YOUR.par 0 20

to convert snapshot 0 to 20 related to YOUR.par file. You can find more information at convert page.