Partial Differential equation: Createpde. f as afunction

Hello, Using Createpde, how can I define f as a function (for example a Step function), instead of a constant?

Answer 1

[Torsten]

Take a look at the example

"Coefficient Handle for Nonconstant Coefficients"

under

https://uk.mathworks.com/help/pde/ug/pde.pdemodel.specifycoefficients.html

f = @fun;

%Set the coefficients in a 3-D rectangular block geometry.
model = createpde();
importGeometry(model,"Block.stl");
CA = specifyCoefficients(model,"m",0,...
                               "d",0,...
                               "c",1,...
                               "a",0,...
                               "f",f);

%Set zero Dirichlet conditions on face 1, mesh the geometry, and solve the PDE.
applyBoundaryCondition(model,"dirichlet","Face",1,"u",0);
generateMesh(model);
results = solvepde(model);

%View the solution on the surface.
pdeplot3D(model,"ColorMapData",results.NodalSolution)

function f = fun(location,state)
  f = location.y.^2.*tanh(location.z)/1000;
end