PyFreeFEM¶

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

Note

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

Features¶

PyFreeFEM has the following capabilities:

Running FreeFEM .edp scripts that support python input parameters:
python Executing script.edp with input parameters f, N and THREEDIM¶
```
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:
freefem DEFAULT, IF and ELSE 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:

python Getting the FEM matrix¶

 1from pyfreefem import FreeFemRunner
 2
 3fem_matrix="""
 4IMPORT "io.edp"
 5mesh Th=square($N,$N);
 6fespace Fh1(Th,P1);
 7varf laplace(u,v)=int2d(Th)(dx(u)*dx(v)+dy(u)*dy(v));
 8matrix A = laplace(Fh1,Fh1,tgv=-2);
 9
10exportMatrix(A);"""
11
12#Get the sparse matrix (scipy csc_matrix format) A:
13runner = FreeFemRunner(fem_matrix)
14exports = runner.execute({'N':100})
15A = exports['A']
16print('A=\n',A.todense())

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

python

13runner = FreeFemRunner(fem_matrix,debug=10)
14exports = runner.execute({'N':100},verbosity=0)

yields the following output:

console

$ 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.

bibtex

@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.