Have a look at src/dm/impls/plex/examples/tests/ex26.c It does exactly this (among other stuff) using exodus format
Blaise > On Nov 28, 2018, at 1:51 PM, Danyang Su via petsc-users > <[email protected]> wrote: > > Dear All, > > My simulation needs to pass initial condition from external file to the code. > The initial condition in the external file is given in the natural ordering, > which is consistent with the original input mesh file in VTK format. In the > previous development, I use label to save all the local vertex numbering to > global natural numbering. The code works, but it is not efficient in > DMPlexDistribute when the mesh size is increased with a huge number of > different labels. > > I am looking for a more efficient way to pass the natural ordering data and > let each processor read the local owned data (either with or without ghost > nodes). I am trying to use DMPlexGetGlobalToNaturalSF and generate local node > index to global natural node index. Due to my lack of knowledge about graph > theory, I am a bit lost. Is there any example available to do this? > > Thanks, > > Danyang > > > -- Department of Mathematics and Center for Computation & Technology Louisiana State University, Baton Rouge, LA 70803, USA Tel. +1 (225) 578 1612, Fax +1 (225) 578 4276 http://www.math.lsu.edu/~bourdin
