Q about matsingle

Satish Balay balay at mcs.anl.gov
Tue Apr 11 12:45:59 CDT 2006


On Tue, 11 Apr 2006, abdul-rahman at tu-harburg.de wrote:

> 
> 
> On Tue, 11 Apr 2006, Satish Balay wrote:
> 
> > That would be --with-precision=single. However PETSc currently doesn't
> > compile in this mode.
> >
> > Satish
> 
> Thanks for telling me. saves me from compiling. Out of curiousity, what is
> matsingle for? Is it also not usable?

Even matsingle is not tested for complex mode. [Both
--with-precision=single,matsingle should work for the default
--with-scalar-type=real mode]

matsingle mode stores the matrix in single precision - but all
operations are done in double precision.  This is a performance
optimization mode [the performance gain is from the lower memory
bandwidth requirements of this single precision matrix storage].

Satish




More information about the petsc-users mailing list