On 18 Apr 2014, at 17:52, Mike Sussman <[email protected]> wrote:

> Folks,  I recently upgraded my 13.04 system to 13.10 using the update 
> manager.  I had only two problems with the update (a bug in the python idle 
> program and some minor difficulty with the network manager applet) but I had 
> a great deal of trouble getting FEniCS working.  Mike Welland gave me some 
> excellent advice that I could not do without, too.  I would like to share my 
> experiences so others can avoid them.
> 
> I had been using FEniCS for a while before the upgrade, going through the 
> "Chapter 3" tutorial, so I had a little bit of experience running it.  After 
> the upgrade, and mindful of the warning on the web pages 
> http://fenicsproject.org/download/ubuntu_details.html, I followed the 
> directions there, re-adding the ppa and updating everything.  Unfortunately, 
> the very first of the tutorial examples failed with a long error message 
> that, as best as I could tell, indicated that a file was not found.  I posted 
> a question on this list and Mike Welland responded with some suggestions, but 
> it was only after I began inserting print statements into some python modules 
> that I was able to discover that the missing file was swig and dolfin was 
> trying to check the version number.  Sure enough, swig had not been installed 
> during the upgrade, so I installed it.
> 
> Following the swig installation, the tutorial exercises got only to the next 
> error: "Exception: Incompatible swig versions detected. UFC swig version is 
> not the same as extension module swig version: '2.0.10' != '2.0.8'"  
> Inexperienced as I am, I did not appreciate the meaning of this error 
> message, and spent some time cleaning fenics off my system and then 
> re-installing it, all to no avail.  Finally, after seeing a reference to the 
> "~/.instant" directory in this list, I removed that directory (I guess it 
> contains cached compilations from my earlier runs on 13.04) and, voila, 
> everything works nicely now.
> 
> As a consequence, I have some suggestions:  
> 
> In the first place, the fenics .deb package should depend on swig, so that 
> swig gets installed when fenics is installed.  In addition, a sensible error 
> message when swig is not present would be helpful for inexperienced users.  
> 

Strange. When I check the dependancies via the package manager for 14.04, I see 
Swig as a required package. Johannes Ring, the maintainer of the packages, 
should be able to respond.


> A second suggestion would be to recommend cleaning out the ~/.instant 
> directory after a system upgrade among the other suggestions on the web page 
> referenced above.  It might also be possible for instant to add some mention 
> of ~/.instant in its error message about incompatible swig versions.  
> Alternatively, instant (or dolfin) could be configured to recompile instead 
> of throwing an error when the swig version doesn't match.
> 

Good suggestion. We did discuss this a few years back when the Debian packages 
were first created. I recall that it’s a Debian policy that packages cannot 
automatically clean out cache files, so a helpful message to run instant-clean 
would be in order. Could you register this point as an issue on Bitbucket 
(https://bitbucket.org/fenics-project/dolfin/issues)?


> Thanks again to Mike Welland for his help, and to the rest of you who post to 
> this list with helpful comments.

Thanks for the feedback.

Garth

> _______________________________________________
> fenics-support mailing list
> [email protected]
> http://fenicsproject.org/mailman/listinfo/fenics-support

_______________________________________________
fenics-support mailing list
[email protected]
http://fenicsproject.org/mailman/listinfo/fenics-support

Reply via email to