On 2/21/13 7:11 PM, Jed Brown wrote: > > On Thu, Feb 21, 2013 at 6:07 PM, Boyce Griffith <griffith at cims.nyu.edu > <mailto:griffith at cims.nyu.edu>> wrote: > > > Yes there is a local and global size. They are both 0. :-) > > > > Heh, interesting. Most finite-dimensional vector spaces have a > dimension. May as well use VecNestGetSubVec() when needed. I don't think > there is any code that will short-circuit in the zero-size case, but I'd > still encourage you to state a dimension that's not obviously bogus.
For better or for worse, the "size" of the wrapped data can change dynamically. Somehow it seems less dishonest to set the size to 0 instead of, e.g., 1. At least when you get 0 you know that the size is bogus! :-) We've been using this stuff for ... a while now, and it hasn't caused any problems. That said, I would prefer to have tighter integration with PETSc. I think that DMComposite is what I was thinking might work. -- Boyce
