surface area of any gmsh model imported to fipy

Question

I would like to calculate the shell surface of any mesh imported into fipy via gmsh similar to cell Volumes:

sum(mesh.cellVolumes) 

So far i have located the outside Faces with:

    f = FaceVariable(mesh=mesh,value=False, name='Aussen')
    f.value[where(mesh.exteriorFaces == True)] = True 

I would like to sum the faceVolumes if those exist in fipy somewhere, is this the way to go?

Answer 1

This should do it,

import numpy as np
from fipy import Grid2D

mesh = Grid2D(nx=2, ny=2)

np.sum(mesh._faceAreas[mesh.exteriorFaces.value])

The above seems to require .value for the "take" on face areas to work correctly.

It's worth doing mesh._ and then hitting tab in ipython to see all the extra attributes available for meshes. There are a lot of hidden ones.

Edited to make the code a full working example.