d82cc36c5a
OpenFOAM can now be compiled with single, double or long double scalars by setting the WM_PRECISION_OPTION environment variable to either SP, DP or LP respectively. On most 64bit systems long double is stored as 128bit but computed in the floating point hardware to 80bit. Due to the increased storage compared to double precision cache and memory access is significantly more time consuming causing a slow-down of floating point intensive operations by a factor of 2 to 3.
OpenFOAM Configuration
The main OpenFOAM settings are located in the parent etc/ directory. The bash and csh shells are supported and to configure OpenFOAM source etc/bashrc or etc/cshrc respectively which source the following files in the config.sh or config.csh respectively:
settings: core settingsaliases: aliases for interactive shellsunset: sourced to clear as many OpenFOAM environment settings as possiblempi: MPI communications library settingsensight: application settings for EnSightparaview: application settings for ParaViewscotch: application settings for compiling against scotchmetis: application settings for compiling against metis 5
The config.*/example directories contains various example configuration files for the corresponding shell:
compiler: an example of fine tuning ThirdParty compiler settingsopenmpi: an example of fine tuning openmpi settings for OpenFOAMparaview: an example of chaining to the standard config/paraview with a different ParaView_VERSIONprefs: an example of supplying alternative site-defined settings