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4) Modify source code
a) You can find the main GEM routines under .../gem/src/*/*, for example :
...
.../gem/src/rpnphy/surface
Find and edit the routines you want to modify.
b) Recreate the executable
Once you modified the routine(s) you want you need to recreate the executable.
Make sure you are To do this you need to go back in the 'build' directory!
Only if you add any new routines or add include files or module "use" lines to an existing routine you first need to recreate the dependencies and make files by re-executing the full cmake command under point 4d3d) again - see above.
Otherwise, it is enough to just re-execute:
make -j4 workmaingemdm
If you just want to compile a routine without creating the executable (to save time) you can just compile a routine, for example utils/sfclayer_mod.F90 with:
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