Add FENICS_EPS

[Anders Logg (Chalmers)]

We have DOLFIN_EPS. In line with from fenics import *, we should add an alias FENICS_EPS.

[Anders Logg (Chalmers)]

Fix issue #781: Add FENICS_EPS

→ <<cset 7a345ad039b1>>

[Prof Garth Wells]

Doesn't seem like a good idea to me. Unnecessarily adding two ways to do one thing.

[Anders Logg (Chalmers)]

It's an alias in the same way as we have from fenics/dolfin import *. I don't foresee adding more of these (possibly fenics_parameters.xml). Most of our users are not aware of DOLFIN and other components, they only know FEniCS. Plus it's a tiny amount of code duplication of code that has remained static for years.

[Prof Garth Wells]

I don't like the fenics alias either. If a user doesn't know what they're using they should find out. Having two names for the same package is just confusing.

[Anders Logg (Chalmers)]

I'm of the opposite opinion. We've emphasized the FEniCS branding for many years. 99% (or some other large fraction) of our users can't name and don't care about any of the components that make up FEniCS, and they shouldn't have to.

[Prof Garth Wells]

It depends on which segment of the market you value most.

[Jan Blechta]

Demos have traditional from dolfin import *. Others teach new users to from fenics import *. This is exactly what creates confusion. Either the library is DOLFIN or FEniCS. We should pick one and follow it consistently.

[Anders Logg (Chalmers)]

I've been teaching numerous courses and tutorials that use FEniCS and I can tell you what is most confusing is to ask users to import dolfin. No one knows what dolfin is. Having fenics as an alias for most users to use is not confusing. We also import ufl.* into the fenics/dolfin namespace. We could be very strict and silly and import neither but it would make a crappy user experience.

[Anders Logg (Chalmers)]

The really logical thing would be to not import ufl.* into dolfin but instead create a new module named fenics which imports ufl.*, dolfin.* and, possibly, mshr.*. What we have now essentially does this without the need for creating a separate top-level repository for the fenics module.