Problem handling 2.0 format in version 2.5

[robertf]

My software produces .feb files using the version 2.0 format, with the tag <febio_spec version="2.0">. I understand that the format changed in version 2.5 but I don't have time to update my software at the moment. When we run FEBio 2.5.1 we get an error message like the following:
FATAL ERROR: invalid value "xyzuvw" for attribute "fix.bc" (line 1477)
The same file runs fine in version 2.4.3. It seems that 2.5.1 doesn't know how to handle the old format but doesn't know that it doesn't. Is it supposed to handle it? If not, could a better error message be output?
Thanks.

[maas]

Hi Robert,

FEBio 2.5 handles the degrees of freedoms (dofs) differently than previous version and the new approach is not fully backward compatible (this only affects fixed bcs by the way). Although most combinations of dofs are still supported, the particular combination you mention is not. That said, it is easy to add support for that combination, so I will go ahead and do so. It will be supported in FEBio 2.5.2 and we'll try to upload this version in the next few days.

In the mean time, you could try the following work-around. If the model to which you are applying this fixed bc is not a shell, then you don't need the "uvw" part. Only the "xyz" is used by solid elements. If you are fixing dofs of shells, you could split the definition in two since both the combinations "xyz" and "uvw" are supported.

Best,

Steve

[robertf]

Thanks for the usual quick and helpful reply, Steve.
I guess this change is part of the new format specification mentioned in the release notes for 2.5? Is FEBio supposed to recognize that my file says it's version 2.0?
(By the way, the release notes for 2.5 say 'R E L E A S E 2.4.1 12/11/2015' for the new notes. A bit confusing ...)

[maas]

Hi Robert,

FEBio 2.5 (and future versions) will continue to read the older 2.0 format in addition to the new 2.5 format. Although the 2.0 format is considered deprecated, we have no plans to stop supporting it for the immediate future.

Cheers,

Steve

[maas]

Hi Robert,

The FEBio 2.5.2 version is available from the website. Please give it a try and let us know if you still experience issues.

Cheers,

Steve

[robertf]

It works great :-) Thanks!

[robertf]

One of the students in my f-e course is running FEBio on a Mac. Even with 2.5.2.8514 he gets the xyzuvw/fix.bc error. Is it possible that the Mac version wasn't updated correctly?

[dsrawlins]

Hi Robert,

The Mac version should have the same update. Could you attach the .feb file that is causing the problem?

Thanks,

Dave