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regression-tests/driven_cavity_test.sh

 #!/bin/bash
 
+#################################
+# Driven Cavity Regression Test
+#################################
 
+# build VirtualFluids accordingly to our specific test scenario.
+# in this case adding -DUSER_APPS="apps/gpu/LBM/DrivenCavity to the cmake command is not necessary, because the DrivenCavity is added to VirtualFluids by default.
 mkdir -p build
 cmake -B build --preset=gpu_make -DCMAKE_CUDA_ARCHITECTURES=75 #-DUSER_APPS="apps/gpu/LBM/DrivenCavity"
 cd build && make -j 8 && cd ..
 
-
+# execute VirtualFluids
 ./build/bin/DrivenCavity
 
-
+# set the path to the produced data
 PATH_TO_DIR=output/DrivenCavity
-PATH_TO_REFERENCE_DIR=regression-tests/reference_data/regression_tests_gpu/DrivenCavity
 
+# set the path to the reference data.
+# `regression-tests/reference_data` is fix `regression_tests/gpu/DrivenCavity_2Levels` must match the structure in https://github.com/irmb/test_data:
+PATH_TO_REFERENCE_DIR=regression-tests/reference_data/regression_tests/gpu/DrivenCavity_2Levels
 
+# execute fieldcompare (A more comprehensive manual can be found here https://gitlab.com/dglaeser/fieldcompare)
 fieldcompare dir $PATH_TO_DIR --reference $PATH_TO_REFERENCE_DIR --include-files "*.vtu"
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regression-tests/regression-tests.sh

 #!/bin/bash
 
+#################################
+# VirtualFludis regression tests
+#################################
+
+
+# 1. Cloning the reference data from github
 mkdir -p regression-tests/reference_data
 git clone https://github.com/irmb/test_data regression-tests/reference_data
 
+# 2. set up the python environnement
+#    by cloning our meshio patch and fieldcompare into a venv
 python3 -m venv .venv
 source .venv/bin/activate
-
 pip install rich
 pip install git+https://github.com/soerenPeters/meshio@update-pyproject-version
 pip install git+https://gitlab.com/dglaeser/fieldcompare
 
+# 3. Running the specific tests
+./regression-tests/driven_cavity_test.sh
+
+
 
-./regression-tests/driven_cavity_test.sh
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+# How to add a new regression test?
+# 1. setup the specfic simulation and run it to create reference data.
+# 2. fork https://github.com/irmb/test_data and create a pull request containing the reference data.
+# 3. copy ./regression-tests/driven_cavity_test.sh and adjust the file accordingly to the new test scenario.
+# 4. execute this file from here accordingly to line 18.
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