specifyCoefficients not passing state sturcture as I would expect

Hello,

I'm trying to solve a PDE iteratively and for the f funtion (i.e. the right hand side of the PDE) I constructed a function dependent on state.u, which, based on the page for "f Coefficient for specifyCoefficients" I thought it would basically pass the past solution found using solvepde. However, that does not seem to be the case. When I put a stopping point inside the function, state.u is just the number zero and does not change with each iteration. How can I get this state variable to properly be the last solution generated by solvepde?

Additionally, the location.x, location.y, and location.z variables are all just the number zero, while this certainly should not be the case.

I can look at the soution made by solvepde and it is what I would expect, not zero, so I know the issue is not that.