Hello.
Do you currently have support for the heat equation with non-constant coefficients?
$$\frac{\partial u}{\partial t} = \frac{\partial}{\partial x} \left( k(x) \frac{\partial u}{\partial x} \right),$$
or, alternatively,
$$\frac{\partial u}{\partial t} =\frac{\partial^2}{\partial x^2} \left( k(x) u \right),$$
where u(x,t) is the solution and k(x) is the variable coefficient.
Thank you for considering this question.