Awesome- that is easy. How do I access that SF? On Thu, Aug 23, 2012 at 12:54 PM, Matthew Knepley <knepley at gmail.com> wrote: > On Thu, Aug 23, 2012 at 1:42 PM, Chris Eldred <chris.eldred at gmail.com> > wrote: >> >> I need the adjacency relations discussed in my other post- the only >> one that is not part of closure(p) U star(p) is: U >> cone(support(edge)). Given an edge p, I need all of the edges that >> cover the same cell as edge p. > > > Okay, then for parallelism, I think you need nothing more than the SF we get > from Jacobian preallocation. > > Thanks, > > Matt > >> >> On Thu, Aug 23, 2012 at 12:17 PM, Matthew Knepley <knepley at gmail.com> >> wrote: >> > On Thu, Aug 23, 2012 at 12:26 PM, Chris Eldred <chris.eldred at gmail.com> >> > wrote: >> >> >> >> Yes- I am implementing the TriSK scheme >> >> (www.mmm.ucar.edu/people/skamarock/Ringler_et_al_JCP_2009.pdf) on >> >> arbitrary Voronoi meshes. In order to do wind/flux reconstruction at >> >> the cell edges, it needs to know about the edges of adjacent cells- >> >> which are outside of closure(p) U star(p). >> > >> > >> > Great! Stuff that cannot be done with that structured crap. However, >> > from >> > quickly looking at >> > the paper, there is nothing beyond the neighbors, so we can reuse the >> > code >> > from >> > Jacobian preallocation. If you could tell me exactly what adjacency you >> > need, we might be >> > able to do it even more simply. >> > >> > Matt >> > >> >> >> >> On Thu, Aug 23, 2012 at 11:16 AM, Jed Brown <jedbrown at mcs.anl.gov> >> >> wrote: >> >> > On Thu, Aug 23, 2012 at 12:12 PM, Chris Eldred >> >> > <chris.eldred at gmail.com> >> >> > wrote: >> >> >> >> >> >> Thanks- that helps a lot. If I need stencils that are larger than >> >> >> closure(p) U star(p) (for a higher-order finite difference method, >> >> >> for >> >> >> example), I assume that I need to create my own PetscSF's that >> >> >> describe which points need to be ghosted? >> >> > >> >> > >> >> > Is this still a fully unstructured method? The Sieve formalism >> >> > doesn't >> >> > give >> >> > you a very efficient way to do this for structured or semi-structured >> >> > grids. >> >> > >> >> > Even so, if wider stencils are to be supported, I think it should be >> >> > implemented within the library. Doing it outside with the current >> >> > infrastructure is going to be quite a rabbit hole. >> >> > >> >> >> >> >> >> Is there some documentation or example code that explains the theory >> >> >> behind star forests? >> >> > >> >> > >> >> > Docs for the basic operations: >> >> > >> >> > http://59A2.org/files/StarForest.pdf >> >> >> >> >> >> >> >> -- >> >> Chris Eldred >> >> DOE Computational Science Graduate Fellow >> >> Graduate Student, Atmospheric Science, Colorado State University >> >> B.S. Applied Computational Physics, Carnegie Mellon University, 2009 >> >> chris.eldred at gmail.com >> > >> > >> > >> > >> > -- >> > What most experimenters take for granted before they begin their >> > experiments >> > is infinitely more interesting than any results to which their >> > experiments >> > lead. >> > -- Norbert Wiener >> >> >> >> -- >> Chris Eldred >> DOE Computational Science Graduate Fellow >> Graduate Student, Atmospheric Science, Colorado State University >> B.S. Applied Computational Physics, Carnegie Mellon University, 2009 >> chris.eldred at gmail.com > > > > > -- > What most experimenters take for granted before they begin their experiments > is infinitely more interesting than any results to which their experiments > lead. > -- Norbert Wiener
-- Chris Eldred DOE Computational Science Graduate Fellow Graduate Student, Atmospheric Science, Colorado State University B.S. Applied Computational Physics, Carnegie Mellon University, 2009 chris.eldred at gmail.com
