Assigning different physical groups to different color in gmsh and mark them as different material in fenics

[dokken]

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How to define a subdomain using material data (from data file)?

First of all, does your mesh consist of triangles or quadrilaterals? Secondly, is your mesh uniform and structured (i.e. is it a RectangleMesh with 100 x 100 cells?) I would suggest something like: from dolfin import * import numpy as np mesh = UnitSquareMesh(100, 100) V = FunctionSpace(mesh, "DG", 0) u = Function(V) dx = 1/100 values = np.arange(100*100) local_values = np.zeros_like(u.vector().get_local()) for cell in cells(mesh): midpoint = cell.midpoint().array() i = int(midpoi…

Which writes the data to a function, Which you can write to xdmf