subsection Initial temperature model
  set Model name = function

  subsection Function
    set Variable names      = x,y,z
    set Function constants  = p=0.01, L=1, pi=3.1415926536, k=1
    set Function expression = (1.0-z) - p*cos(k*pi*x/L)*sin(pi*z)*y^3
  end
end
