Fenics solver implementation in 1.12.1

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Fenics solver implementation in 1.12.1

tkdiff
I am attempting to try to use the Fenics solver with Featool 1.12.1 with no success so far - I must be missing something simple.  I have Fenics installed per instructions with Featool in a Windows 10 WSL using Ubuntu 18.04.  That went successfully.  However, when I try to run a problem using the Fenics solver from the GUI,  I just get an error window saying the output file couldn't be found.  A couple of questions to start with:
1. I have matlab and licensed Featool installed on my C drive in the usual spot, but the WSL/Ubuntu is installed on my D drive to use the additional space.  Is Featool expecting Fenics to be in a certain place and is not locating it?  How can I point Featool to the right place?  
2.  Does Ubuntu and Fenics have to be running in a shell window to be accessible?
3.  The problem I'm trying to solve is a time dependent diffusion problem with time stepping.  Although I don't get any error in this regard, I'm wondering if Fenics can solve it.  I noticed in the 1.12.1 writeup that time dependent problems were now possible.
I am not a Linux expert, so please understand.
Thanks,
Tom
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Re: Fenics solver implementation in 1.12.1

tkdiff
I got it working.  I tried deleting the D drive version of Ubuntu and let Windows install it as normal, where-ever that is, on the C drive.  I also installed the Python components separately and it worked, including for time step non linear equation solving.  I did notice a couple of quirks I'd appreciate a comment on:

1.  When the fenics solver is complete and returns control back to featools, the last line is "Deleting Fenics data and log files".  Depending on the solver variables, like total time, that I set, sometimes the command log window puts a blue bar over that line and sits there for 5-20 seconds, evidently executing the file cleanup, before it allows any further activity in the featool app, ie, it hangs it for that amount of time.  Is this normal?

2.  With my diffusion problem, to get a converged solution using the internal solver, I had to scale the numbers by using the base 10 log of them, ie,  log10(c).  However, fenics did not recognize either log10 or log.  Does fenics only respond to numbers, not equations, for constants or equations?
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Re: Fenics solver implementation in 1.12.1

Precise Simulation
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Thank you for reporting the issue with FEniCS and how you resolve it.

tkdiff wrote
1.  When the fenics solver is complete and returns control back to featools, the last line is "Deleting Fenics data and log files".  Depending on the solver variables, like total time, that I set, sometimes the command log window puts a blue bar over that line and sits there for 5-20 seconds, evidently executing the file cleanup, before it allows any further activity in the featool app, ie, it hangs it for that amount of time.  Is this normal?
A significant delay during cleanup is not be typical, but could technically occur if you have a lot of or particularly large files (time-steps) to be cleaned up. Or it could potentially be a file system issue with locking/releasing permissions.

tkdiff wrote
2.  With my diffusion problem, to get a converged solution using the internal solver, I had to scale the numbers by using the base 10 log of them, ie,  log10(c).  However, fenics did not recognize either log10 or log.  Does fenics only respond to numbers, not equations, for constants or equations?
I believe FEniCS should technically be able to handle most mathematical expressions (as "log" should be converted to "ln" by FEATool). For log10 a web search gives me this link to this older post https://fenicsproject.org/qa/10021/solving-expression-with-log10 which does not seem so clear. I would suggest you maybe try to get in touch with the developers of/support for FEniCS to clarify what is supported and what to do. When you know the correcy syntax you should be able to simply edit the translated "featool-fenics.py" script in the "FEniCS" dialog box.