PyFreeFEM

PyFreeFEM is a python package interfacing FreeFEM scripts with Python. .edp scripts become small modules that can be used as building blocks of a main python project.

PyFreeFEM is different from the alternative pyFreeFEM module from Olivier Devauchelle, which has been developped rather simultaneously for similar purposes.

Official documentation

Features

PyFreeFEM has the following capabilities:

• Running FreeFEM .edp scripts that support python input parameters:

  from pyfreefem import FreeFemRunner   
  FreeFemRunner("script.edp").execute({'f':'x+1','N':10, 'THREEDIM':0})
  

• Executing portions of .edp scripts conditionally to python input parameters by using special preprocessing instructions:

  DEFAULT (THREEDIM,0)    
  
  IF THREEDIM    
  mesh3 Th=cube($N,$N,$N);
  ELSE   
  mesh Th=square($N,$N);
  ENDIF
  

• Automated imports and exports of data structures (floats, arrays, matrices, meshes) from FreeFEM to Python and vice-versa:

  from pyfreefem import FreeFemRunner   
  
  fem_matrix=""" 
  IMPORT "io.edp"
  mesh Th=square($N,$N); 
  fespace Fh1(Th,P1);    
  varf laplace(u,v)=int2d(Th)(dx(u)*dx(v)+dy(u)*dy(v));  
  matrix A = laplace(Fh1,Fh1,tgv=-2);    
  
  exportMatrix(A);"""    
  
  #Get the sparse matrix (scipy csc_matrix format) A:    
  runner = FreeFemRunner(fem_matrix)
  exports = runner.execute({'N':100}) 
  A = exports['A']
  print('A=\n',A.todense())
  

• Flexible debugging and capturing of FreeFEM standard output: running the previous script with

  runner = FreeFemRunner(fem_matrix,debug=10)
  exports = runner.execute({'N':100},verbosity=0) 
  

  yields the following output:

  $ python test.py 
  Write /tmp/pyfreefem_xsd1x5dw/run.edp
  Reset directory /tmp/pyfreefem_xsd1x5dw/ffexport
  FreeFem++ /tmp/pyfreefem_xsd1x5dw/run.edp -v 0 -nw
  Saved /tmp/pyfreefem_xsd1x5dw/ffexport/matrix_A
  Finished in (0.06s)
  A=
   [[ 1.  -0.5  0.  ...  0.   0.   0. ]
   [-0.5  2.  -0.5 ...  0.   0.   0. ]
   [ 0.  -0.5  2.  ...  0.   0.   0. ]
   ...
   [ 0.   0.   0.  ...  2.  -0.5  0. ]
   [ 0.   0.   0.  ... -0.5  2.  -0.5]
   [ 0.   0.   0.  ...  0.  -0.5  1. ]]
  

Contribute and support

• Issue tracker: https://gitlab.com/florian.feppon/pyfreefem/-/issues
• Source code: https://gitlab.com/florian.feppon/pyfreefem

If I am not responding on the issue tracker, feel free to send me an email to florian.feppon[at]kuleuven.be

Citation

Please cite the following reference when using this package:

FEPPON, Florian. Shape and topology optimization of multiphysics systems. 2019. Université Paris-Saclay. Thèse préparée à l'École polytechnique.

@phdthesis{feppon2020,
   author = {Feppon, Florian},
   title =  {Shape and topology optimization of multiphysics systems},
   school = {Th\`{e}se de doctorat de l'Universit'{e} Paris-Saclay pr'{e}par'{e}e
      \`a l''{E}cole polytechnique},
   year = {2019}
}

Licence

PyFreeFEM is a free software distributed under the terms of the GNU General Public Licence GPL3.