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tools/mapping-tester/README.md

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+# Mapping tester
+
+The mapping tester is a collection of scripts and templates that lets you generate, run, post-process and collect a huge catersian product of settings.
+
+Settings include: ranks, meshes, and mappings and their settings
+
+For performance profiling, it allows enabling synchronization and configuring repetitions
+For mapping tests, it provides post-processing scripts and a configurable reference function
+
+## config-template.xml
+
+This is the setup of ASTE, which will be used.
+This doesn't need to be changed for most scenarios.
+
+## setup.json
+
+This describes the setup including general information and execution groups.
+
+General information includes, repetitions, the function to generate data, the rank configuration, and solver meshes.
+
+Each execution group specifies which mapping and constraint to run using which meshes.
+This is necessary for running a range of RBFs with mesh-specific configurations.
+
+## generate.py
+
+This generates all cases including run scripts in the given outdir based on `setup.json` and `config-template.xml`.
+Meshes are prepared in the next step.
+
+## preparemeshes.py
+
+This looks up input meshes in the general section, evaluates the function to generate data and then partitions them for all requested rank configurations.
+These meshes are the written to `outdir/meshes`.
+When handling multiple cases, you can symlink them to a single directory to prevent duplication.
+
+## Running
+
+You can use environment variables `ASTE_A_MPIARGS` and `ASTE_B_MPIARGS` to pass custom arguments to `mpirun` for each solver.
+This is useful to pin CPUs on a local node or pass hostfiles on a cluster / in a SLURM session.
+See more information [on running simulations in our docs](https://precice.org/running-overview.html).
+
+Each case can be run individually using its `run.sh` or every case in sequence using `outdir/runall.sh`.
+
+A finished run generates a file called `done` in the case directory. This allows you to see the amount of finished jobs using:
+
+```bash
+find -name done | wc -l
+```
+
+## Post processing
+
+This post-processes the mapped meshes and evaluates accuracy metrics of the mapping accuracy.
+Hence, this step is only required if you are looking for mapping accuracy results.
+Each case can be run individually using its `post.sh` or every case in sequence using `outdir/postprocessall.sh`.
+
+This however can take a very long time. Consider running all post-processing scripts in parallel using GNU parallel:
+
+```bash
+find -name post.sh | parallel --bar bash {}
+```
+
+Use the saved time to cite the project.
+
+## gatherstats.py
+
+This generates various statistics for each case and aggregates them into a single CSV file.
+
+## plotconv.py
+
+This reads the stats file, averages the runs and plots various convergence statistics.