> On Jul 16, 2015, at 11:14 AM, Jed Brown <[email protected]> wrote: > > Gianluca Meneghello <[email protected]> writes: > >> Hi again, >> >> I am now trying to write a vector to an HDF5, this time using a DM >> structure to impose the vector layout. >> >> Creating the vector with (as in src/dm/examples/tutorials/ex10.c) >> >> DMCreateGlobalVector(da2D,&gauss); >> >> every works fine, i.e. the hdf5 file has the correct layout given by the >> dimension of the DM. On the other side, if I use: >> >> VecCreate(PETSC_COMM_WORLD,&gauss); >> VecSetSizes(gauss,PETSC_DECIDE,Nx*Ny); >> VecSetDM(gauss,da2D); > > VecSetDM only associates a DM with the Vec. It does not interpose > itself into VecView. > > Should we change this so that creating a Vec of the correct size/block > size/layout and associating a DM is equivalent? Perhaps, but it's more > nuanced than it might seem.
Yikes. VecSetDM() seems a very dangerous and odd thing. Should it exist? If it exists it seems it should be exactly equivalent to creating the vector from the DM. > > Why don't you want to just call DMCreateGlobalVector()?
