[petsc-users] petsc-3.5 quadruple precision mixed with double

[Jed Brown]

Hao Zhang <hbcbh1999 at gmail.com> writes:

> It's 3d incompressible RT simulation. My pressure between serial and
> parallel calculation is off by 10^(-14) in relative error. it eventually
> build up at later time. 

I doubt that is why your solution develops artifacts after many time
steps.  If you're using __float128, you'll take a big hit on performance
so you might as well make everything __float128 (PetscScalar).  Mixing
precisions is a maintenance burden and exactly the wrong thing when
you're trying to rule out potential sources of error.
-------------- next part --------------
A non-text attachment was scrubbed...
Name: signature.asc
Type: application/pgp-signature
Size: 832 bytes
Desc: not available
URL: <http://lists.mcs.anl.gov/pipermail/petsc-users/attachments/20170629/103e98b2/attachment.pgp>