[petsc-dev] [petsc-users] ublas sparse matrix bindings?

[Jed Brown]

On Tue, 29 Jun 2010 15:26:38 -0500, Matthew Knepley <knepley at gmail.com> wrote:
> I am not so sure here. Our problem is not with type parametrization so much
> I think (since MatScalar is there)
> but with mixing this with another value type. I suspect that a templated
> version would have 1G of compiler
> errors right now.

PETSc's philosophy often involves moving the solver to the highest level
of control (instead of rolling loops around the solver as an ad-hoc way
to answer a question of interest).  If you have matrices/vectors with
different scalar type/precision, then you would naturally want entries
of mixed type within single matrices and vectors (and usually mixed type
within blocks associated with nodes/cells of your discretization).  C++
templates are pretty much inadequate for this because you would want to
flatten the recursive types (not to mention the error message and
compilation time insanity).

Jed